Anth 102
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102
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Anthropology
Date
Oct 30, 2023
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Introduction to Human Evolution- TOPIC 1
What is anthropology?
● The study of humankind
● The study of all aspects of the human species, including our biology, culture, and
language
● The science that investigates human biological and cultural variation and evolution
4 subfields:
1. cultural - looking at societies that are alive
2. Archaeology- looking at the material culture; not alive
3. Linguistic- looking at the language evolution
4. Physical (biological)- human evolution and variation of both past and present
Biological (physical) anthropology: ● Variation-
○ differences between individuals within a population and between populations
○ Anthropologists are interested in the variation in terms of both biology and culture
○ Variation is important because without it there would be a lot more extinction
● Evolution- change over time
○ Cultural and biological
○ The study of the change in allele frequencies over time
■ Everytime a baby is born it displays this allele frequency
4 Subfields of Biological Anthropology:
1. Paleoanthropology- study of the human fossil record, paleolithic archaeology
2. Human genetics- study of human genome
3. Primatology- study of human primates
4. Osteology- study of skeletons
Hominin VS Hominid:
● Hominin- humans and all humanlike ancestors after the split between chimpanzees and
humans (more narrow)
● Hominid- great apes, humans, and their ancestors (more broad)
Primates:
● Group of mammals in the order primates
● Share characteristics:
○ Large brains
○ Forward facing eyes
○ Increased reliance on visual sense
○ Fingernails
○ Reduced sense of smell
● They Humans:
are: apes, humans, old world/new world monkeys, tariser
What's unique about humans?
● Bipedalism- using two legs to walk
● Non- honing complex- no spaces between canines, reduced in size and shape
● Material culture- we rely on material objects
● Symbolic behavior
○ Material culture
○ Language
○ Speech- increase chance of survival
● Hunting
● Domestication of food items
The Scientific Method:
1. Observe a natural phenomenon
2. Collect data
3. Propose hypothesis and test them
4. Draw conclusion
Characteristics of Science:
● Scientists believe that an organized reality exists in nature
● Things that occur through natural processes that can be studied
● Principles can be formulated to explain how things work in nature
○ Ex: how raindrops are formed
How we know what we know: ● Origin of bipedalism
○ Darwin hypothesis:
■ Environment change
■ Freed hands for tool use- by walking on two feet you can carry the tools that you created with
your hands
○ Data:
■ Upright walking evolved in forest habitats
■ Stone tools were much later
■ Hypothesis rejected
● Natural processes govern how different kinds of creatures appear and how creatures are
transformed from one kind to another
● Theory: a general statement intending to explain nature that is confirmed by evidence such
that it can be predicted the new, as yet unobserved phenomena
Some theories: 1. Germ theory of illness 2. The round earth theory
Characteristics of Science:
● Facts- verifiable truth
● Inference- conclusions drawn from evidence
● Hypothesis- a testable explanation of observed facts (an educated guess)
● Testability- scientific hypothesis must be testable
● Theory- a hypothesis that explains concrete facts, have been tested and cant be
rejected
1. Observation- problem identified
2. Hypothesis- testable explanation of observed facts ex: dark colors attract heat better
than light colors
3. Hypothesis tested- this is where you can get a verifiable truth
4. Theory - a hypothesis that explains concrete facts, have been tested and cant be
rejected
Theory of Evolution:
● Change over time
● Evolution is a fact
Scientific Theory:
● Natural selection is the scientific theory that explains how organisms are biologically
transformed
○ Natural Selection is survival of the fittest:
■ Heredity differences give a higher rate of survival
■ Peppered moth*
● Inorder for Natural selection to happen you need:
○ Variation- individuals in a population vary from one another
○ Inheritance- parents pass on traits to their offspring
○ Selection- some variants produce more than others
○ Time- successful variations accumulate over time
● Natural selection acts on the traits you already have
● Adaptation- advantageous changes brought by natural selection. Increased survival
○ Morphological ○ Physiological ○ Behavioral
Evolution by Natural Selection explains:
● Appearance of new diseases
● Evolution on antibiotic resistant bacteria
● Fossil record: extinct species, new species
● Relationships between organisms
Development of evolutionary Theory- TOPIC 2
Pre-scientific European views:*
● Grand design- G-d created the world
● Stasis- the world is a fixed and unchanging because it's perfect
● Great-chain of Being- life is arranged the simplest to complex
The scientific Revolution: The path to natural selection-
● Nicolaus copernicus:
○ Heliocentric theory- earth is around the sun
● Galileo Galilei:
○ First use of telescope to study stars
○ Universe is dynamic
○ Earth moves and is not a focal point
● Keppler, Descartes, and Newton- established laws of physics, motion, and gravity
● *John Ray- 1 genus multiple species
○ First definition of genus and species ■ Cains= genus
● Genus familiar
● Genus lupus
● Genus rufus
● Carolus Linnaeus- proposed a system of classification. “Father of Modern Taxonomy”
● Classification goes from broad to specific
● John Baptiste Lamarck-
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○ proposed a hypothesis of how human evolution occurred within the species level but has been
rejected
○ Ex: if you dye your hair pink then it will be passed to your offsprings
○ They try to modify their phenotype but that won't be transferred to its offspring ○ It was the first
attempt to explain evolution
○ It was about inheritance of acquired characteristics
■ Traits acquired during life passed on to the offspring
● Georges cuvier
○ Introduced the concept of extinction and the theory of catastrophism
○ Things happen in nature and it will lead to catastrophic events ex: extinction of
dinosaurs
○ He thought the earth was only thousands of years old
● Charles Lyell-
○ Father or geology
○ He realized the earth was millions of years old
○ Uniformitarianism- earth's features result from long term processes that operate
in the present as they did in the past. “The present is the key to the past”
○ Unless there are geological disturbances the older things are on the bottom
● Thomas Malthus
○ Intrigued by the amount of resource and population
○ Population growth is kept in check by resource availability
○ When resource goes down competition goes up
● Charles Darwin*
○ Theory of Natural selection
○ Interested in: biological variation within a species is critically important
○ Interested in: sexually reproduction plays a role in increasing variation
● Alfred Russell Wallace
○ Came up with the same conclusion as Darwin
○ Worked in south america but mostly southeast asia
○ Independently developed theory of natural selection
○ Both him and Darwin are credited for the theory of natural selection*
Principles of Inheritance- TOPIC 3 Evolution:
● Two types:
○ 1. A change in the genetic structure of a population- microevolution. Ex:
everytime a baby is born (alleles will be different in the child)
○ 2. Appearance of a new species- macroevolution
■ Takes a very long time (millions of years)
Darwin's Postulates:*
Need these 4 to happen in order to have Natural Selection:
1. Competition- Populations can grow infinitely, but environment limits growth
2. Organism must vary within population
3. Variation affects the likelihood to survive, reproduce
4. Variations transmitted from parents to offspring
Natural Selection- mechanisms for change favoring the survival and reproduction of some
organisms over others because of hereditary differences between them.
Fitness:*
● The potential- measure of relative reproductive success of individuals (men can have way
more than women)
● May vary with the environment Reproductive success:
● The actual- how many offspring an individual has that survive to reproduce themselves
Selective Pressures:
● Forces in the environment that influence reproductive success in individuals Evolutionary
change through Natural Selection:
1. Traits must be inherited
2. Traits must vary between individuals
3. Fitness is a relative measure that changes as the environment changes
Perceived problems with Darwins:
● Blending inheritance- they thought that you were half your mom and half your dad
● Selection depletes variation- they thought variation disappears
● How can selection lead to new types not seen in ancestral population?
Blending inheritance:
● Offspring will have a mix of parental traits
Selection depletes variation?:
● Meiosis adds variation
● Might be other variation that we cant see with our naked eye
● By reproducing you add variation
● Artificial selection brings variation
Darwin couldn't resolve these issues:
● He didn't have a physical model for how genetic transmission works
Gregor Mendel:
● Basis of genetic inheritance
● Experiments provide foundation for genetic information
Mendel's experiments:
● Pure breeding population of plants- same traits across generations
● He crossed different pure breeding plants
● F0- parental generation
● F1- first hybrid generation
● F2- second hybrid generation
● TT= two dominant alleles (homozygous)
● tt= two recessive alleles (homozygous)
● Tt= one dominant allele and one recessive allele (heterozygous)
1 TT= tall 2 Tt= tall 1 tt= short. 75% tall and 25%short
Results:
● Traits are controlled by discrete units- genes
● Genes occur in pairs- 1 from mom and 1 from dad
● Meiosis is when egg and sperm cells combine through fertilization
● Genotype reflects phenotypes
● Alleles- different versions of a gene (ex: TT,Tt,tt)
● This system applies to all species but not all genes
● Observed characteristics of organisms are determined jointly by two particles (alleles),
one from mom and one from dad
● EX: shoe box= gene and Shoes= alleles Definitions:
● Humans have 46 chromosomes and 23 pairs
● Gene- a sequence of DNA coding for a protein
● Locus- particular position where you find a particular gene
● Allele- different versions of the gene at a locus
● Genotype- particular combination of alleles
● Phenotype- how the genotype is physically expressed
● Homozygous- two copies of the same allele
● Heterozygous- copies of two different alleles
DNA:
● Trapped in the wall of the nucleus
● RNA is what transfers the DNA
● karyotype*- picture of the 23 pairs of chromosomes
● “X” chromosome is necessary
Mendel's 1st Principle: adding variation
● Principle of segregation- gametes receive individual allele
○ Gamete production- genes separate so each gamete contains one member of a
pair
○ Fertilization- full number of chromosomes is restored
● Found that one trait can mask another Medel also performed crosses with two traits:
Mendel's 2nd Principle
● Principle of independent assortment- genes controlling different traits are inherited
independently if they aren't linked (not on the same chromosome)
Linkage- when genes are located on the same chromosome Recombination (crossing over)
● The exchange of genetic material between homologous chromosomes during meiosis
● When does this happen? Before the first cell division
● It increases phenotypic variation and genetic variation
● It happens only during meiosis
Mendelian Traits
● Combination of genes that are going to determine the visible characteristics that an
individual is going to display
● Characteristics that are influenced by one pair of genes
● Sickle-cell anemia and Tay Sachs diseases are mendelian traits
● A one to one relationship
○ If you have one copy (only one allele coding for that particular trait) you'll display that trait
Cell, Chromosome, and Molecular Genetics: pt.1 TOPIC 4 The cell:
● Basic unit of life
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● Prokaryotic cells
○ Single celled organisms (Bacteria)
○ 3.7 bya
● Eukaryotic cells
○ Have a nucleus
○ 1.2 bya Cell Membrane:
● Protects inner content and made of proteins Cytoplasm:
● Consists of liquid
● Within the cell membrane
● Contains organelles
Organelles:
● Functional structures in the cytoplasm
○ Ribosomes- manufacture proteins
○ Mitochondria- generate cells energy
○ Nucleus- contains chromosomes, and hence genetic material (DNA and RNA)
Two types of cells: 1. Somatic:
a. Body cells
b. Via mitosis (2 diploid)
Gametes:
a. Sex cells
b. Via meiosis (4 haploid) Genetic Material- DNA VS. RNA
DNA: ● ● ● ● ●
RNA: ● ●
DNA: ● ● ●
DNA: ● ●
DNA: ● ● ● ●
(ATCG)
Double stranded
Contains genetic information
Directs function in the cell
Codes for biological structures
Information for- building, operating, and repairing organisms
(AUCG):
Single stranded
Similar in structure to DNA
Early Research:
DNA”discovered” in the 1950’s
Watson and crick in 1953
Rosalind franklin also helped determine DNA structure- X-rays
Genes and Chromosomes:
Chromosomes- DNA sequence bound by proteins in long strands Genes- section of DNA with
identifiable function, such as protein
Structure:
2 strands arranged in a double helix
Sugar-phosphate strands held together with nitrogen bases
*The basic unit of DNA is the nucleotide- Sugar, Phosphate, and Base The bases- A,T,C,G
DNA: Functions:*
● 1. Replication- copies the entire strands of DNA.
○ Strands separate to be replicated to heal wounds and repair body tissues , for cells to multiply
● 2. Protein synthesis- copies only the gene that lets you produce a protein ○ Making proteins
Replication: MITOSIS
1. Enzymes break bonds between 2 DNA strands
2. Each nucleotide chain is template for new nucleotide strands
3. Unattached nucleotides pair with appropriate complementary nucleotide
4. End result- two newly formed strands of DNA
5. Each new strand is joined to one of the original strands of DNA
Protein Synthesis:
● ●
Protein- one or more chains of amino acids (n=20) 20 different amino acids Protein functions-
○ ○ ○
○ ○
○ ○
Structural components of tissues
Enzymes initiate or enhance chemical reactions
Hormones- travel through the bloodstream to promote or reduce activity of tissues/organs
Regulatory proteins- turning on or off certain genes
Protein synthesis entails amino acid chains assembled into protein molecules in the cytoplasm
Amino acids link to form a polypeptide chain
protein= one or more polypeptide chains folded into a complex structure
DNA*
Double stranded Sugar - deoxyribose Base- ATCG
RNA*
Single stranded Sugar- ribose Base- AUCG
RNA:*
1. mRNA- takes message from nucleus to out of nucleus (codon)
2. tRNA- take amino acids to ribosomes (anticodon)
3. rRNA- stabilizes mRNA and tRNA bond during protein synthesis
Protein Synthesis:
Step one- Transcription
● The process of coding a genetic message for proteins by formation of mRNA
● Gene’s DNA sequence is copied as mRNA
○ mRNA leaves nucleus to where protein production occurs ● Each DNA triplet code for one
amino acid
Step two- Translation
● mRNA codon matched with tRNA anticodon. Each tRNA carries a specific amino acid
● rRNA stabilizes the mRNA and tRNA bond and the amino acids are joined together
Step by step of translation:
○ mRNA leaves the nucleus and attached to a ribosome
○ tRNA carries over the appropriate amino acids
○ Ribosome moves down the mRNA chain exposing more “instructions”
○ tRNA continues to drop off amino acids
○ The process continues until the entire mRNA sequence has been read and a
chain of amino acids has been formed
● EX: ATG (DNA- Triplet) → UAC (mRNA-Codon) → ATG (tRNA-Anticodon)
● 3 bases is called a triplet ex: ATG
*Sequence on test and we need to pair with the right copy EX: ATCCG→ UAGGC (codon)
DNA: Genes
● * What is a gene?
○ A portion of that DNA codes for a polypeptide chain (AKA protein) ● Does all DNA within an
organism contain genes?
○ NO!
○ Only 2% of our DNA contains genes to make proteins.
DNA: Genes, Inrons, and Exons:
● 98% introns
● 2% extons
● mRNA contains ONLY exons
DNA: Regulatory Genes:
● Effecting if genes are activated or not activated
● These genes regulate the expression of other genes
● 98% of our DNA is the same as a chimpanzee however our regulatory genes shut on
and off certain genes that make us look phenotypically different
● Archaepteryx- some say this was the last of the dinosaurs before the evolution of birds
○ They had teeth
○ Birds are the living descendants of a group of dinosaurs
○ Birds don't produce teeth because regulatory genes were turned off at some
point in their evolutionary history
○ Molecular scientists have been able to activate these regulatory genes
● Homeobox genes- genes regulating embryonic development
● Hox genes- A subgroup of homeobox genes that are directly involved with how the body
develops meaning where the body parts develop
○ On a dipteran fly there is only one set of wings. Haltere is one pair of club shaped
organs in a dipteran fly that are the modified second pair of wings and function as sensory flight
stabilizers. After the genetic modification of Hox Genes they fly grew a second pair of wings in
replacement of the haltere
○ Hox genes usually result in miscarrage
○ Antennapedia: hox gene defect resulting in legs growing in place of antennae in
fruit flies
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○ Hox genes are shared between organisms the only difference is the degree of complexity
■ The human hox system is simply a more elaborate version of that found in a fly
Cell, Chromosome, and Molecular Genetics: pt 2
DNA: Universal Genetic Code
● All life either has one or both DNA or RNA
○ This implies a common ancestry for all life ● Organisms differ in DNA arrangement
Mutation:
● Force of evolution
● Change in genetic code
● It can be a single point mutation which only involved a single base
● *sickle cell anemia
○ One single based being modified affect the shape of the blood cell of an individual and the life
of that cell is shorter
○ Its a single point mutation
○ Causes an individual to die younger
○ AA= normal
○ AS= resistant against malaria
○ SS= sickle cell anemia (die)
Chromosomes:
● Pieces of DNA wound up around proteins
● Two copies of each chromosome (1 from M & 1 from D)= homologous chromosomes
● *Homologous chromosomes are NOT necessarily genetically the same because alleles
can differ within the gene
○ They have the same genetic loci but might not be genetically the same
○ Alleles = different version of a gene
Types of Chromosomes: 1. Autosomes
a. Not sex chromosmes
b. Physical characteristics
2. Sex Chromosomes- defines the individuals sex
● 22 pairs of autosomal chromosomes
● 1 pair of sex chromosomes
● 23 pairs of chromosomes
● 46 chromosomes
Two types of cells:
● Diploid- mitosis
○ Full set of chromosomes- 2 of each
○ Somatic cells- body tissues
● Haploid- meiosis
○ 1⁄2 number of chromosomes- 1 of each
○ Gametes each have 23 chromosomes Mitosis: DNA replication
● Cell division in somatic cells
● Original cell produces 2 identical daughter cells (diploid)
● Growth, repair/ replacements of tissues
● As we age the process becomes sloppy
Steps in Mitosis: 1 cell division which is producing two cells that are identical to the one you
want to replace
1. 46 double stranded chromosomes (homologous) line up at the center of the cell
2. Chromosomes pairs split and then move to opposite ends
3. Cell membrane pinches in and 2 new cells formed
Meiosis:
● Gamete production
● 2 cell divisions result in 4 haploid gametes
● Evolutionary, meiosis is very important because it increases genetic diversity
Steps in Meiosis:
● Two cells divisions
Recombination (crossing over):
● The exchange of genetic material between homologous chromosomes during meiosis
● This shuffles linked genes
● This does not happen during mitosis
● Source of genetic variation
Meiosis vs Mitosis:
● Meiosis- DNA recombination
● Mitosis- DNA replication
Evolutionary Significance of Meiosis:
● Natural selection acts on phenotypic variation
● Meiosis increases genetic variation faster than mutation
● How does meiosis increase genetic variation?
○ 1. Independent assortment- genes on different chromosomes can be combined in novel ways
○ 2. Recombination- genes on the same chromosomes (linked) can be combined in novel ways
*in which ways can we add genetic variation to a population? 1. And 2.
Problems with Meiosis:
1. Non- disjunction
a. The failure of homologous chromosomes or chromosomes strands to separate
during cell division ● Two types:
○ Trisomy- extra chromosome (3 instead of 2)
○ Monosomy- missing chromosome (1 instead of 2)
Monosomy: Turner Syndrome- X0 (mutation)
● Absence of a sex chromoskme
● Biologically designated as female
○ Short stature
○ Broad chest
○ Webbed neck
○ Low set ears
○ Non-functional reproductive organs
Trisomy: Downs syndrome- (mutation)
● Extra copy of the 21st chromosome
○ Cognitive impairment ○ Small chin
○ Round face
○ Almond shaped eyes ○ Large tongue
○ Heart defects
● This is the only autosomal trisomy allowing survival to adulthood
● *Trisomy 21 = down syndrome
● *What # is affected by down syndrome and in what way? A: 21 and there are 3
● *it's the only autosomal trisomy allowing survival to adulthood
Trisomy: Klinefelter’s Syndrome (mutation):
● 3 copies of sex chromosomes- XXY
● Male with extra X chromosome
○ Small testicles
○ Reduced fertility
○ Feminine characteristics ○ 1/1000 male births
Trisomy: XYY genotype (mutation):
● 1/1000 live male births
● Taller than average
● No obvious symptoms or abnormalities
Problems with recombination:
● Getting a chunk but not giving back
Cri-du Chat (Cats cry) Syndrome (mutation):
● 1/50,000 live births
● Loss of portion of chromosome 5
● Abnormal development of vocal tract, also affects mental and facial development
Prader-Willi Syndrome (mutation):
● 1/10,000- 1/25,000 live births
● Loss of portion of chromosome 15
● Weak as infants , poor sucking reflex
● By age 5 or 6 they will have compulsive eating
Mendelian Inheritance in Humans: Genetic Disorders:
● Autosomal disorders:
○ Dominant disorders: 1 copy of allele to be expressed
○ Recessive disorders: 2 copy of allele to be expressed
● Sex-linked disorders: controlled by loci on sex chromosomes
○ X- linked ○ Y-linked
Autosomal Dominant: Trait- Brachydactyly B= normal
b= has it
Ex: BbXbb
● This will end up having 50% chance of having a baby with Brachydactyly
Autosomal Recessive: Trait- Albinism (albino) A= normal
a= has it
● 2 copies of the gene needs to be expressed
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● Caused by a lack of melanin production
Hemophilia:
● Can not clot blood
● X-linked trait
● Males can't be carriers and not express it because it's an X- linked disorder and they
only have one X
● Hemizygous- has one member of a pair of alleles
● X-linked traits more common in males because they only have one
H= normal h= has it
● X^hY: male with hemophilia
● X^hX^H= female carrier
● X^hX^h= female with hemophilia
Non-Mendelian Pattern of Inheritance: Polygenic Traits
● Polygenic traits- a trait that is affected by multiple genes. (2+ genes: 1 trait)
○ These are genes that don't follow the 1:1 pattern which is that 1 gene has 1 effect on the
phenotype
○ Many different genotypes and phenotypes can result
○ Continuous traits: series of measurable intermediate forms between two
extremes. Ex: skin color
○ Environmental influences impact trait expression (nutrition influences height)
○ *height, eye color, skin color = polygenic traits
● Pleiotropy- when an allele affects more than one trait (1 genes: 2+traits)
○ * the gene that affects the increasing wing also affects the breath of the bird
○ Dimitri Belyaev- fox breeding experiment
The Gene-Biological Effect Relationship
1. Single gene- single effect = each gene has a distinct biological effect. 1:1 ratio
2. Polygenic trait- multiple genes affect one trait
3. Pleiotropy- one gene affects multiple traits
4. Polygenic trait and pleiotropy
Recall: Perceived Problems with Darwin's Idea:
1. Blending inheritance- genetic inheritance is not a “blending” process because you have
both D and R alleles.
2. Selection depletes variation- yes, but new variation is generated by other processes like
mutation, independent assortment and crossing over
3. How can selection lead to new types not seen in ancestral population? Because much
variation is hidden in the recessive alleles. Ex: CF and albinism
* Natural selection can’t see if you're a carrier unless you see it on a phenotypic level
The Modern Synthesis: Combining Darwin’s ideas with Modern Genetics
● Continuously varying characters (like height) affected by many genes
● Low mutation rates maintain variation, as does recombination (independent assortment,
crossing over), and the “hidden variation” of recessive traits
● Natural selection acts on phenotypes and results in gene frequency changes across
generations (evolution)
Forces of Evolution- TOPIC 5
● Forces of evolution are natural processes leading to genetic change
○ 1. Mutation
○ 2. Natural selection
○ 3. Genetic drift
○ 4. Gene flow- keeps the species together as one
1. Mutation:
● In order for a mutation to be passed down in needs to be in the gametes
● A mutation is an actual change in genetic material, in the DNA
● Any particular mutation is rare
● By mutation we create new alleles and therefore have new genetic coding
● Types of mutation *:
○ Single DNA base mutation
■ Base change (point mutation) or insertion or deletion
■ Sickle cell anemia- instead of having circle red blood cells its “C” shape
○ Change in chromosome structure
■ Portion of chromosome deleted or duplicated
■ Cats cry syndrome, prader willi syndrome
○ Addition or loss of entire chromosome
■ Down syndrome
■ Turner syndrome
■ XXY, XYY genotypes
● Effects of Mutation:
○ Can produce new genes/alleles, provide variation for natural selection
○ Rare, often may not have big effect on evolutionary change
○ Frequency of new allele can be affected by genetic drift
○ May have a large effect if mutation is in a homeobox gene (regulates
development)
● Evolutionarily significant if they occur in gametes
● Mutation rate range: from 1 to 100 mutations per million sex cells for a single-base
mutation in humans
● There are known mutations in humans
● *mutations are very rare
● Achondroplasia- dominant mutation and occurs in the gametes
○ Most common form of dwarfism
○ Cartilage doesn't grow properly
○ Caused by dominant gene
○ dd= normal
○ Dd= dwarf
○ DD= won't be born
○ Approx. 1 in 25,000 births
2. Natural selection:
● NS= mechanism for change favoring the survival and reproduction of some organisms over
others because of hereditary differences between them.
○ Traits need to be passed down in order for the organism to survive
● Adaption= any trait (physical, biochemical or behavioral) resulting from natural selection
giving an advantage
○ Not all traits are adaptations
○ All adaptations are traits
● Ex: population with blue eyes and green eyes people→ disease kills all blue eyed people →
left with only green eyed people
● Galapagos island- they had a drought and therefore the beak size changed among the birds.
No rain will affect the vegetation which will affect the nutrients of the animals.
● Directional Selection- pushing distribution to the extreme that allows the individual to survive
the most
● stabilizing selection (balancing/heterozygous selection)- selecting for the average
3. Genetic Drift
● random effect on allele frequency of a population
● larger effects on a small population
● key factors
○ 1. random change in genetic makeup of population
○ 2. small population is affected most
○ 3. changes can occur as “accidents” aka “sampling error”
● the smaller the population the greater genetic drift
● founder effect- different phenotypic and genotypic levels from the larger population
○ you have a population with a mixture of genes, small group leaves to make a new population
and then by chance you have unusual allele frequencies
○ ex: dunkers
4. Gene Flow
● the glue that keeps a species together
● interbreeding between people from different populations
● if you can’t interbreed then gene flow has been discontinued
Evolution is a multi-step process:
1. production of variation- mutation
2. shuffling of alleles to create new variation- independent assortment and crossing over
3. distribution of variation- genetic drift and gene flow
4. natural selection- acting on this variations
Human Biocultural Evolution- new topic
● interaction of cultural techniques and biology
● lactase persistence- producing the enzyme to help you digest milk
● sickle cell disease
● balanced polymorphism (heterozygous advantage)- the maintenance of two or more
alleles in a population due to the selective advantage of the heterozygote Sickle cell anemia:
abnormal hemoglobin
● variants- A and S
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● 96% of hemoglobin in adults is A
● Abnormal hemoglobin (S) molecule distorts Red Blood Cell
● abnormal RBC shape can lead to tissue damage
● AA = you can get malaria in a place infested with malaria
● AS = you won’t get malaria but you might get a cold
● SS = you have the disease
● as human population started modifying the environment and it made it better for
mosquitoes to develop
○ increased frequency of malaria selects for heterozygote
○ S allele maintainer at high frequency
Lactase Deficiency
● this has to do with your ancestry
● Lactase- an enzyme that breaks down sugar in milk (lactose)
● dominant allele that results in the ability to produce lactase throughout life- Lactase
persistence
● individuals with the recessive homozygote have difficulty in digesting milk (lactose
intolerance)
○ diarrhea
○ cramps
○ other intestinal problems EXAM 2:
Human Biology and Adaptation- Topic 1 Types of variation
● Within group- differences between individuals in the same group
○ This is greater than between group because they are able to move around
● Between group- differences in the average phenotype in different groups What is a race?
● A group of populations sharing phenotypic and cultural traits that distinguish them from other
such groups
○ This is wrongly applied to humans because we think race equals color immediately when it
should not
● Applied sloppily in humans: skin color, national origin, religion European Racial Classifications
1700’s
● In the 1700’s there were 3- 9 races
○ Ex: mongoloid, negroid, caucasoid
○ People have different opinions of how many race classifications there are
Race... not biologically supported
● Race is a cultural construct and not a concept for which we can find support using
biological data.
○ There is no evidence for shared genetic material only shared by members of a
“race”
● Race relies extensively on skin color as one of the main traits used to differentiate
people.
● However, there is no clear correlation between skin color variation across the globe
and other biological markers (Blood type distribution, genetic markers) thus the
concept of race is not a biologically meaningful concept.
● Based on phenotypical differences observed by early scholars
○ Skin color
○ Body configuration
○ Cranio-facial morphology
● The system of race is failing because there isn't a definite amount of race classification
European Racial Classifications 1700’s
● The false belief that intellect and cultural factors are genetically inherited
● Biological variation in skin color does NOT support a system of racial classification Human
Variation
● Complex traits like skin pigmentation are continuous; race categories are discrete
○ The more sun someone is exposed to the darker the skin color
○ So the closer you are to the equator the darker someone will be
Settlement history of U.S.
● Institution of slavery strongly influenced percepition of race
Correspondence of Different Traits
● A meaningful race concept would have to work for a number of independent traits
○ Ex: blood type, skin color, genetic markers
● Different traits lump different human populations together
Traits: No correlation between any of these which shows that race isn't supported biologically
1. Worldwide distribution of skin pigmentation
2. Worldwide Blood Type A distribution
3. Worldwide Blood Type B distribution
4. Contour of genetic similarity- 120 genes, 42 populations
Race concepts assume between group variation is greater than within group variation
● The assumption is incorrect
● Blood groups and other genetic polymorphisms show that:
○ 88-90% of human genetic variation found within groups
○ Between group variation accounts for 10-12% of the total genetic variation
because gene flow is discontinued
● Chimpanzee subspecies- between group variation is greater
● Human populations- within group variation is greater Conclusions on “Race”
● Race concept lacks biological support
● False belief that intellect and cultural factors are predominantly genetically determined
● Race concepts assumes that one’s own group is superior to other groups
● Racism is a cultural, not biological phenomenon, and is found worldwide
Human Variation: Biological Perspective
● SKIN COLOR: human variation now studied in light of evolutionary forces
○ Gene flow
○ Genetic drift
○ Natural selection
Clinal Variation
● Gradual change in allele frequencies over geographic space
The Adaptive Significance of Human Variation
● Some human variation reflects adaptation to environmental conditions
○ Genetic adaptation: evolutionary changes characterize all individuals within a population or
species.
■ Regulated by our genes
● Genetic adaptations to heat evolved in our ancestors
○ Sweat glands: 3-4 liters/hour short periods
○ Vasodilation
Other types of Adaptations- * test- know the shortest to the longest and examples of all 3.
Influenced by our environment:
1. Acclimation- short term physiological response to stress- can last from minutes to hours. Ex:
increased respiration rate at high altitude, running to catch a bus that only comes every hour
2. Acclimatization- long term physiological response to stress- can last for days to months. Ex:
tanning, increase in RBC production at high altitudes
3. Developmental acclimatization- changes in organ or body structure that occur during growth
as a response to environmental stress. Ex: increase in chest size during growth at high altitudes
Human Adaptations to Climate
1. Skin color
2. Body size and shape
3. Chest and lung size
Pigmentation and Geography
● Before 1500, skin color followed a geographical distributions
● Greatest amount of pigmentation found in tropics
● Lighter skin color found in more northern latitudes
Why Darker pigmentation at low latitudes (near the equator)? *test
1. Skin cancer- avoid skin cancer because higher levels of skin cancer are in lighter
skinned people
2. Folate destroyed by UV- avoid folate destruction. Folate deficiency leads to disorders in fetal
development and sperm production
Why Lighter pigmentation at high latitudes (away from equator)?
1. Because they aren't exposed to the sun as much and therefore have low Vitamin D
production which can cause rickets*
Adaptive explanations for the relationship between pigmentation and latitude
● Low latitudes (near the equator)
○ High UV
○ Darker skin
■ Reduced folate destruction
■ Reduce likelihood of skin cancer
● High latitudes (away from equator) ○ LowUV
○ Lighter skin
■ Facilitates vitamin D production
Adaptations in Humans
● Genetic adaptations- evolutionary changes that characterize individuals of a specific
species or population which is controlled by our genes that are affected by
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environmental changes.
● Acclimation (short term)
● Acclimatization (long term)
● Developmental acclimatization
Body Size and Shape
Climate and Morphological/ size/ shape Variation
● Bergmann's Rule- body size is greater in populations living in colder climates
decreasing surface area/volume ratio.
○ Broader chests are found in organisms that develop in colder environments
○ If you are cold adaptive then you will have a larger chest and less SA
○ If you are heat adaptive then you’ll have a smaller chest and more SA
○ Higher temp= smaller chest size
○ Lower temp= bigger chest size (keep you warm)
● Allen’s Rule- mammals in cold climates tend to have short and bulky limbs (decreases
SA/volume). Mammals in hot climates tend to have longer, slender limbs (increases SA/volume)
Cultural Adaptation
Different environment = different adaptations
● High Altitude Stress:
○ High alt. = 2500 m/ 82000 feet
○ Hypoxia- oxygen starvation frequently occuring at high altitudes
■ People living in Machu Picchu developed larger lungs/chests so that they can breathe better
in higher altitudes
■ Environment leads to change in the human body
● Visiting High altitudes: acclimation and acclimatization
○ Increased respiration rate- acclimation
○ Increased heart rate - acclimation
○ Increased RBC production - acclimatization
● Developmental acclimatization
○ Chest size difference between high and low altitudes of native peruvian
populations
● Regional Differences in Human Body Form and Pigmentation
○ Some differences reflect adaptations to different environments
○ Some of this variation reflects genetic adaptation, but much is a result of
developmental acclimatization
■ Body size
■ Limb proportions
■ Chest size
○ You can have differences between body form without major genetic differences
between populations ● Intelligence
○ Both genetic and environmental factors
○ IQ scores measure life experience as well as intelligence
○ No convincing evidence that populations vary in intelligence
Other factors in Human Variation
1. Sexual variation
2. Human growth and development (life history)
3. Nutrition
4. Activity levels
1. Sexual variation
● Hair distribution- males have more hair on face, chest, and back
● Difference in body mass, facial shape, deepening of voice
● Secondary sexual characteristics
2. Human growth and development (life history)
● At age 6, the baby's brain has reached full size and nearly complete development
● Relative to other mammals
○ Long childhood with little growth
○ Adolescent growth spurt
○ Long post-reproductive life- grandparents
3. Nutrition
● Variation due to nutrition
4. Activity Levels
● Variation due to activity levels
● Variation due to different activity levels
Macroevolution and systematics- TOPIC 2
● The classification of living things
● Microevolution- genetic change in population from one generation to the next
● Macroevolution- new species
● Systematics- species that go together
● We like to classify things together
*The Path to Natural Selection
● Species can interbreed and have babies
● John ray
○ First definition of genus and species ● Carolus Linnaeus
○ System of classification
○ He laid the basis for taxonomy
*The classification of living things
● Phylogeny- a family tree for a group of organisms sharing a common ancestor
● Systematics- explores relationships among organisms; construction of phylogeny
● Taxonomy- the use of phylogenies in naming and classifying organisms; naming stuff
○ Helps you compare organisms
7 basic levels
- phylogeny
- systematics
- taxonomy
Phylogeny for Primates
● New world monkeys- central and south america
● Old world monkeys- africa, europe, and asia
● Basic assumption- species that are phenotypically similar are more closely related
Terms related to Phylogeny Building - you use homologous traits
● In order to construct phylogeny charts you need to pay attention to traits
● Analogous traits- traits similar due to common function but different ancestry
○ Ex: the wing of a bird and the wing of the fly- considered analogous traits because they have
the same function
● Homologous traits- traits similar due to common ancestry - these are the traits used for
phylogeny building
○ Ancestral trait*- trait appearing early in the evolution of a lineage
○ Derived trait*- traits that are modified from the ancestral condition
● Cladistics: uses derived traits to build phylogenies
Molecular Data
● Compare DNA to create phylogenies
● Closely related species have more similar DNA
Species Concepts
● Biological species concept (BSC)
○ Species = group of interbreeding organisms reproductively isolated from other groups
○ Species are maintained by gene flow- interbreeding between populations ○ Gene flow inhibits
population divergence - it prevents separation
○ If there is no gene flow then you will have population divergence
● High Finch Species Diversity
● Allopatric Speciation- this means no gene flow.
○ biological populations of the same species become isolated from each other to an extent that
prevents or interferes with gene flow.
○ No gene flow can lead to macroevolution
● Niche- the way of life of a species
● Rate of speciation- how many new species will arise depends on the number of empty
niches
● Adaptive radiation- rapid diversification by a small number of species to fill many open niches
○ is a process in which organisms diversify rapidly from an ancestral species into a multitude of
new forms
○ Dinosaur went extinct and the mammals speciated since dinos were not ruling anymore
○ Examples of Adaptive radiation ■ Finches
■ Mammals after dinosaurs went extinct
Paleospecies
● Organisms we can identify based on fossils
● Physical similarity (morphology)=genetic relatedness
How does speciation happen? New species arising
● Anagenesis: “Straight line evolution”
○ Single species evolving into new species over time
○ Evolve phenotypically and genetically
○ They don't exist during the same time
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○ Ex: Homo Habilis → Homo Erectus
● Cladogenesis: “Branching” Evolution
○ Formation of one of more new species from another overtime
○ Departing from species A (species A remains the same) and now are a sub
group called species B that looks different than species A
○ They exist at the same time
How Speciation frequently occurs
1. Reproductive isolation- discontinuation of gene flow
2. Genetic Divergence- genetic drift, mutation, natural selection
Microevolutionary Patterns
● Gradualism- it’s a slow and gradual process
● Punctuated equilibrium- long periods of time with little change (stasis) interspersed with
short periods of rapid evolutionary change The Birth Species
● Gradualism
● Gradualism with increase rate of change
● Punctuated equilibrium = staircase pattern
Characteristics of a primate- TOPIC 3
● Homologous ancestral trait- opposable toe
● Homologous derived trait- humans not having an opposable toe
Why do we study primates?
● Our closest relatives
● Humans are primates
● Similar to us which helps us better understand our own lineage
○ Morphology ○ Physiology
○ Development
Homology- traits similar because of common ancestry ● Wild chimps- they are our closest
relatives
○ Make tools
○ Hunt animals
○ Live in male-bonded groups- males remain with males to prevent interbreeding
and females migrate out
○ Captive chimps can aquire
○ Basic human language skills
Analogy- traits similar thought convergent evolution (adapting to similar environments in similar
ways)- similar traits due to similar function
● Baboons and hominins
○ Live in similar environments
○ Similar food sources
○ Similar selective pressures
Characteristics- all primates have these traits ancestrally even though there was some
modification
● Grasping hands and feet, thumb, big opposable toe ○ Evolution of the pentadactyl limb
○ Prehensile hands and feet
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● Fingers, toes w/ nails and not claws
○ No more claws which increases SA of digits and you can pick up small things
● Sense of smell reduced
○ Dogs have wet noses which allows them to smell better
● Visual sense well-developed
○ Energy from smell went to eyesight
● Postorbital bar/ closure
○ *How do strepsirhines differ from haplorhines?
■ Strepsirhines:
● have a postorbital bar
■ Haplorhines:
● have a postorbital closure which completely protect their eyes
○ Allows you to have a good visual sense and protects your eyes ● Small litters, gestation and
juvenile periods long
○ This allows you to develop the large brain ● Large brains
Primate Eutherian VS Primate Cranium
● Postorbital closure- preventing brains of the eyes back and forth
● Stereoscopic vision- allows you to measure distance and have an accurate visual
sense
Primate adult definition
● Incisors- flat and used for nippinh (they are in the front of the mouth)
● Canines- slashing and used in the same fashion as premolars
● Premolars- puncturing and used for eating a carrot
● Molars- grinding
● Humans have the same dental formula as Old World monkeys and apes
Dental Formula- catarrhine vs platyrrhine
● Platyrrhine- new world monkeys
○ 2:1:3:3
● Catarrhine- old world monkeys, apes, humans
○ 2:1:2:3
Expansion of the brain in primates
● Increase in size and complexity of the cerebral cortex
● Reduction of olfactory lobes
Order Primates
● Living primates- 350 species and 70 genera
● Strepsirrhines- lemurs and lorises (postorbital bar)
● Haplorhines- tasiers, NWM, OWM , apes, humans (postorbital closure)
Taxonomic Chart of living primates
● Tarsiers in the haplorhine category= new classification system
● Tarsiers in the strepsirrhine category= old classification system
● Tropical distribution of primates
Locomotion - how do primates get around?
● Arboreal quadrupedalism- they use 4 limbs on branches. They have shorter arms which
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are good to make sure your body is close to the branch so you don't fall
● Terrestrial quadrupedalism- they use 4 limbs walking on the ground
● Vertical clinging and leaping- big hands
● Brachiation- long arms and fingers
● Bipedalism- walking on your feet
Primate Groups/ Characteristics and Distribution
Strepsirhines
● *Features of strepsirhines are p ostorbital bar, tooth comb, wet nose
● *lemurs are only found in madagascar which is NOT in africa
● Lorises are found in africa and southeast asia
● Most “primitive” primates
○ Small brains
○ Wet noses- have a better sense of smell
○ Greater reliance on smell
○ Many nocturnal (active at night and not in the day)
○ Many lack color vision
● Frugivores, folivores, plant gum and insects Lemurs
● Only found in madagascar
○ “Aye aye” type of lemur found in madagascar
○ Bushbaby- they leap from one tree to the next and eat insects
○ Pottos and lorises- they raise their arms to show they are scared to death
Tarsiers
● *found in southeast asia- forests
● Often monogamous- it’s hard for them to find other tarsiers
● Postorbital plate and other anthropoid characteristics
● New classification system= haplorhines
● Nocturnal insectivores
● *most carnivorous primate
Platyrrhines- New World Monkeys
● True moneys
● They live in central and south america
● *which primate has prehensile tails? Platyrrhines
● They are more arboreal than old world monkeys- most use arboreal quadrupedalism
● *They are the most arboreal primates
● Dental formula either- 2:1:3:3 OR 2:1:3:2
● round , sideways oriented nostrils
Cercopithecoidea- Old world monkeys
● Africa and asia
● Generally larger than new world monkeys
● Narrow nostrils facing downwards- same as us
● Very good at adapting to any environment
● Dental formula- 2:1:2:3 (bilophodont teeth)
● Broad array of habitats including dry, open settings
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○ Baboon
○ Vervet- they can produce and alarm call when ones sees a predator (very good
communication)
○ Colobus
○ Langur Hominoidea- Apes and humans
● Orangutan, gibbons found in s outh east asia
● Chimps, bonobo, gorilla in africa
● Humans are closely related to african apes
● Dental formula without bilophodont- 2:1:2:3
● No tails
● Larger, more complex brains than monkeys
● Shoulder blade on back
● Arm easily raised above head
Ape and Monkey characteristics
● Bilophodont vs Y-5 molars
○ Bilophodont teeth= old world monkeys (Cercopithecoidea) have these and eat grass
○ Y-5 molars= this is what apes and humans have (hominids) Gibbons and Siamangs- found in
south east asia
● Smallest apes- 6-12 kg (lesser apes)
● Long arms, curved fingers which allows them to hold onto branches for locomotion in the
arboreal environment
● Brachiate, eat fruits
● Monogamous with EPC
4 Great Apes species *
● Pongo pygmaeus (orangutan)- south east asia
○ 50(F)-100(M) kg
○ Tend to be solitary- the males don’t live with the females it has children with
○ “Four handed” locomotion
○ Frugivorous with some bark, leaves - fruit, bark, leaves
● Gorilla gorilla - africa
○ 100(F)-250(M) kg
○ Tend to live 1 male, multifemale groups- 1 males has control over all the females and mates
with all of them and protects all of them. Known as the silverback gorilla
○ Knuckle Walk
○ Eat leaves, pith, stalks, fruit
○ Tend to be placid, quiet- this is because they save energy to digest what they are
eating so they take naps to gain and save energy
● Pan troglodytes (chimpanzee)- africa
○ 40(F)-50(M) kg
○ They are aggressive
○ Fission-fusion society with male bonding- separating into small groups during
the day to hunt little animals and then at night they come back to the larger group
● Pan paniscus (bonobo)- africa
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○ 40(F)-50(M) kg
○ Fission -fusion
○ Knuckle Walk, more time in trees than chimps
○ Eat fruit, leaves, occasionally hunt small mammals
○ Male and female dominance hierarchies
Primate Ecology and Behavior- new topic 1.Diet and body size
● Tiny primates rely on insects and or gum
● Small primates can eat fruit for carbs and insects for protein
● Medium-sized primates eat fruit for carbs and leaves for protein
● Large primates can rely on abundant but nutrient poor plant foods
Kay's threshold
● Crucial body size- 500 grams —> this size needs a lot of food (frugivores)
● Past this body size you can’t only eat insects
● Below this size you can’t be a folivore
Morphological correlates with diet
● Tooth and gut morphology varied with diet
● Frugivory - fruit
○ Large incisors
○ Molars with low cusps
○ Long small intestine
● Folivory - leaves
○ Small incisors because you are using your canine teeth
○ Shearing crests on teeth
○ Big stomach/large intestine- complex digestive system
● Insectivory - insects
○ Very hyperactive primates
○ Sharp pointed cusps on teeth
○ Simple gut
2. Primate sociality (why do many primates live in groups ?) Proper socialization starts with
mom
● Harlow's isolated infant monkeys from moms
● Deprived infants became poorly socialized adults, bad parents
● Warmth, comfort, and security are important for normal development
Differing reproductive strategies of male and female primates affects sociality
● Females always care for young
● Males don’t
● Why this difference? Females sacrifice and risk their lives to have this baby
Asymmetry in reproductive investment
● In mammals, only females get pregnant and lactate
● Mammals: 90% uneven investment- female give more care than men
● Birds: 90% monogamous
What determines parental investment (CAD V. DAD)
CAD:
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● Care ○ ○
DAD:
● Care ○ ○
by one parent (female) is likely when:
Fitness of offspring raised by one parent is higher Mates are easy to find
by both parents is likely when:
Fitness of offspring raised by one parent is low Mates are hard to find
Benefits of Sociality
● 1. Reduced risk of predation
● 2. Enhanced foraging efficiency
○ More eyes to spot food
○ More individuals to defend resources
● 3. Mutual aid
Costs of sociality
● 1. Increased competition- bigger groups= more competition
● 2. Increased risk of disease
● 3. Increased exploitation by other group members (greater risk of being bullied)
3.Social systems among primates
● solitary= orangutan
● monogamy= gibbons
● Polygyny one-male= gorilla, gelada
● Polygyny multimale= baboons,vervets, chimps (multi female and male)
● Chimps and bonobo: fission-fusion societies
Female dominance hierarchies
● Females just invest in a few offsprings
○ Costly in both time and efficiency
● Female reproductive success is by access to resources- females compete for food
● Competition between females for limited resources leads to dominance hierarchies
Reproductive Success
● Females compete for food
● Males compete for access to females
● Sexual Selection
○ A special category of NS favoring traits that increase success in competition for mates- traits
that will make them (males) more attractive
■ Sexual selection may favor traits that enhance
● A males attractiveness to females (intersexual selection)
● A males competitive ability (intrasexual selection)
Intersextual selection:mate choice *- males attractiveness to females
● Mandrills- dominant males have a colorful tush and if he gets defeated then the
hormones for the color will stop producing and won't be considered attractive anymore
● Vervet monkeys- they have bluish scrotum and that's a trait that will attract females
● Proboscis monkeys- they have a trait of having a big nose which is attractive to
females
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Intrasexual selection: males competing with males to get females *
● Competition for mating opportunities leads to male dominance hierarchies
● Strong selection for traits enhancing competition ability
○ Ex: canine size, body size, testes size (sperm production) 4. Body size and social systems
● Males are larger than females
● One- male, multifemale species= males have bigger canines than females
● Multimale, multifemale species= males are bigger but not as much
Infanticide- abother way males compete *
● Intrasexual competition that only benefits the infanticidal male
● Lactation acts as a contraceptive if nursing is fairly constant
○ Hormone oxytocin suppresses ovulation
● Males kill offspring whose deaths reduce females interbirth intervals
○ Males kills any offspring that does not belong to him
○ Ex: lions, gorillas Altruism
● Action carried that you carry out which benefits the group but not necessarily you
● Ex: grooming - male grooming a female will make her feel relaxed
● Ex: coalitions- females coming together to protect offsprings
● Ex: food sharing
● Ex: alarm callings- vervet monkeys produce at least 3 callings Evolution of Altruistic behavior:
● Kin selection- altruistic behavior is directed at relatives- helping members of your own blood
○ Close kinship facilitates costly altruism
● Reciprocal altruism- beneficial acts balanced between unrelated partners over time
○ Helping someone today and they will help you another time
○ Coalitions between unrelated individuals Social insects: kin selection ex: bees and termites
Evidence supporting kin selection in primates
● Alarm calling to kin
● Foodsharing between kin
● Grooming communication between kin
● Coalition formation between kin
● *Alarm calls: different in terms of frequency and action
○ Snake- look at the ground
○ Eagle- lookup
○ Leopard- jump into closest treet
Conditions for Reciprocal altruism
1. The same individual must have the opportunity to interact with many times
2. Species must have the ability to remember the outcome of the past interaction
3. Individuals must restrict help to those that have helped them in the past
*description of primates and we need to say what it is
Ex: which is not a hominoid? Baboon, bonobos, chimps, gorilla, orangutan A: baboon
Geology, dating, paleontology, origin of mammals- new topic
Deep prehistory- nearly everything that has ever lived is now extinct Paleospecies= fossils
● Morphology (form and structure) is used to group extinct animals into species
● Paleospecies help us date important paleontological sites
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● They are extinct today
Taphonomy
● Everything that has happened to bones from death to discovery
Absolute dating methods
● These methods revolutionized the study of prehistory: potassium-argon dating
● You're providing an actual number
● Dates the volcanic sediments around the fossils Relative dating methods
● Nyayanga- 2.7 mya
● Biostratigraphy
Charles lyell- law of superposition- geology
● Oldest is on the bottom: youngest on the top
● Relative Continental Drift
● Important to date sites and the migrations of certain animals
● The earth's crust is broken up into large, thick plates that drift a top the soft, underlying
mantie
● Continents form part of the crust of these plates and drift with them over the globe
● Movement of the continents
● Formation of mountains is a result of this
Precambrian- all life at sea 600 mya
Fish appear 500 mya
Coelacanth: living lobe-finned fish
370 mya Tetrapods (Amphibians) evolved from a lobe finned fish 340 mya fossil (casineria)
oldest tetrapod with 5 digits:
● Weight supporting backbone
● Strong reptile-like limbs for holding body upright when walking on land
● Five digits which could curl separately
Preadaptation of life on land
● Permian (245-290 mya) diversification of Amniotes
○ Turtles ○ Lizards ○ Birds
○ Dons
○ Mammals
■ Synapsid- mammals are evolving from reptiles
Tetrapod ancestry
● Frogs, lizards, birds, human= homologous and ancestral traits
Mesozoic era: age of reptiles- mammals are alive here
● 65 to 245 mya
● Dinos rule the world
● Egg-laying mammals evolve from synapsid reptiles
● Marsupial and placental mammals evolve
● Birds evolved from dinos
● First angiosperm (flowering) plants
Competition with dinos restrict mammals to a few niches:
● Earliest mammals tend to be small, insectivorous or carnivorous Archaeopteryx:
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● Considered by many as the first bird but retains many dino features
● Others see it as a transitional form between birds and reptiles Reptile Features:
● Teeth
● Flat sternum
● Long bony tail
● Belly ribs
● 3 claws on the wing
Angiosperm plants appear 150 mya- primates were crucial for this Cenozoic Era: age of
mammals
● Today- 65 mya
● Begins with major adaptive radiation of mammals and birds
● 1st clear primates: 55 mya
● First hominins: 6-7 mya
Cetaceans: adaptive radiation of land mammals back to the sea Modern cetaceans have highly
modified forelimbs, no hindlimbs By 40 mya, fully aquatic whales with:
● Tiny hindlimbs
● Ultimately, hindlimbs are lost altogether
Primate Origins and Evolution - TEST 3 Cenozoic Era: Age of mammals
● today - 65 MYA
● Beings with major adaptive radiation of mammals and birds
● plesiadapiforms: 63 mya- most primitive form of a primate- They are potential
primates
● 1st definitive primates: prosimian fossils - 58 mya
● 1st definitive anthropoid fossils- 40 mya
● First hominids: 6-7 mya
Epochs of the cenozoic era
● Prosimians and anthropoids
● Strepsirhines and haplorhines
● Climate has become cooler during the cenozoic
● Climate has become more variable over the last 5 my
Genetic evidence suggests that primates appeared approx 63 mya Primate evolution hypothesis
1. Arboreal hypothesis
2. Visual predation hypothesis
3. Angiosperm radiation hypothesis
Arboreal hypothesis
● Proposed by smith and jones
● Primate traits such as grasping hands and binocular vision were adaptations to life in
the trees
● Moving from ground to the trees caused selective pressures that resulted in the ancestral
primate
● Certain traits will help you avoid predators by adapting to arboreal life
● This fails to explain why squirrels are able to live in trees without those traits Visual predation
hypothesis
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● Challenges arboreal notion: many mammals are arboreal without having evolved primate
traits
● Matt cartmill proposed that primate traits evolved in response to preying on insects and other
small creatures
● The exploitation of small prey resulted in the primate suite of adaptations
● However this does not explain fruit eating primates
● These primates were frugivores so this hypothesis fails to explain everything except
the tarsier who eats insects Angiosperm plants→ flowering plants
● Angiosperm (flowering) plants become dominant by 65 mya (adaptive radiation)
● Primates eat these fruit and then disperse the seeds which help flowering plant
spread
Angiosperm radiation hypothesis
● Randall sussman proposed that primate traits were a response to the development
of fruit-bearing angiosperm plants
○ primates developed their traits in response to the availability of fruit and
flowers following the spread of angiosperms
● Grasping hands and feet evolved for feeding on fruits at the end of branches. Not only getting
away from predators
● Transition from terrestrial to arboreal for nutritional needs Plesiadapiforms- most primitive
primate- 55-65 mya
● U.S., Europe, Asia
● Resemble tropical squirrels
● Very primitive
● Grasping hands
● No postorbital closure or bar
● Projected forward incisors
● Cheek teeth like primates
● big toe with nail
● Stereoscopic vision evolved after grasping hands and feet
Two Well- known groups of early primate fossils- true primates (euprimates)
● *Adapoids
○ Share many primitive features with living lemurs and lorises, ancestor to most modern
strepsirhines
● *Omomyoids
○ Share many primitive features with living tarsiers, haplorhine ancestor
○ Short snout
○ Huge orbits
Genetic evidence- strepsirhines- haplorhine split occurred about 58 mya Darwinius masillae- 47
mya adapoid fossils from germany (frugivore) Anthropoid evolution- El Fayum, Egypt -
33-37mya
● *Catopithecus- dental formula 2:1:2:3 gives us insight to:
○ Evolution of catterhines in africa
○ Small orbits: diurnal
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● Apidium- dental formula 2:1:3:3 gives us insight to Platyrrhines evolution in africa
○ Leaping adaptation in lower limb
■ Deep femoral condyles
■ Short femoral neck
■ Tibia/fibula closely attached
○ Upper limb indicates quadrupedalism
○ Quadrupedal leaper like modern platyrrhines
○ Cranial fragments
■ Short snout
■ Complete postorbital closure
■ Small eyes:diurnal
● Aegyptopithecus
○ Dental formula 2:1:2:3
○ Sexually dimorphic - Males are larger than females
○ Small eyes: diurnal
○ Catarrhine: attached hominoid vs. cercopithecoid divergence
■ Broad spatulate incisors- frugivory
■ Molar cusps and sagittal crest
● shows a possible mixed diet
■ Y-5 molars “dental apes”
■ Arboreal quadrupedalism
○ Dentally looked like an ape
○ Based on the body it looked like a monkey
Miocene Fossil Hominoids
● Golden age of hominoids
● Genetic evidence- monkey- ape divergence at 25 mya
● Geographically distributed
○ African forms
○ European forms
○ Aisan forms
Proconsul - Africa - 17-24 mya
● Skulls and teeth are ape like in appearance (hominoid features)
● Rest of skeleton is monkey- like
● Small brain size
● Small snout
● Y-5 molars
● Arms and legs same length as OW monkeys
● No tail
● Walked on top of branches
● “Dental” ape
Middle miocene ape radiation
● Dry seasonal woodlands
● Apes evolve stronger jaws, thick enamel- eating hard foods
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● Large body size, more time on the ground
Europe- dryopithecus
● First ape where Y-5 molar was described
● Body like living apes
● Flat chest
● Shoulder blade on the back
● Long arms, short legs
● Long, curved fingers- developed if you hang on branches
Asia- Siwalik Hills, Pakistan
● Sivapithecus indicus- *most similar to orangutans (pongo)
○ 8-13 mya
○ Deep, widely flaring zygomatic (cheekbones)
○ Short upper face, interorbital distance
○ I^1 > 1^2 - upper central incisors are larger than upper lateral incisors
○ Orbital shape and facial profile like orangutans
○ Teeth with thick enamel
○ Walked on top of branches
Gigantopithecus
● Biggest ape
● Overlapped with Homo Erectus in Asia (coexisted)
● Large cheek teeth
● Thick enamel- displaying a heavy diet relying on plants like bamboo
Samburupithecus: 9.5 mya
● gorilla - like molars, thick enamel
Victoriapithecidae: 15-20 mya
● ● ●
Apes ● ●
We can link these to cercopithecoids Best known early old world monkeys *bilophodont teeth
and monkey dental characteristics:
Bilophodont teeth= old world monkeys (Cercopithecoidea) Y-5 molars= apes
Reversal of fortune, apes vs. monkeys
● Climate change favored monkeys over apres during the course of the miocene because
monkeys eat a broader range of foods including those found in drier environments
● Environments got cooler, dryer, more seasonal
● Apes largely remained in woodlands and forests, consumed fruit; modern apes are the
descendents of these survivors The Earliest Hominins- new topic Hominin vs. Hominid
● hominin= humans and all human like ancestors AFTER the last common ancestor between
chimps and humans (6-7 mya)
● hominid= primate of the family hominidae that includes great apes, humans, and their
ancestors
The search for the LCA between Humans and Chimps
● Genetic methods- molecular clock
● Fossils finds from the late Miocene and early pliocene
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The molecular clock- takes into account mutation rates
● Over the course of millions of years, mutations may build up in any given stretch of DNA at a
constant rate
● When the stretch of DNA behaves like a molecular clock, it becomes a tool for estimating
when the common ancestor lived
● Rate of change: 1 base per 25 million years *Features of Hominins:
● Bipedalism
● Canine size reduction and shape
Why bipedality? ● Its handy
● Its cool
● Its efficient
Handy
● It frees the hands for
○ Feeding
○ Food transport
○ Tool use and transport
Cool
● Lessens heat stress in direct sunlight
Efficient
● More energetically efficient than chimp knuckle walking
● Variation in energetic efficiency among individual chimps walking bipedally
○ For chimps with longer legs bipedality was more efficient than knuckle walking ● Selection for
energetic efficiency in moving around landscape would have favored
bipedal locomotion, led to evolution of bipedality Hominin
● Bipedal
● Canine reduction
● How to identify bipedal locomotion in the fossil record? (6)
○ Look at the skull
○ Vertebrae
○ Pelvis
○ Femur
○ Tibia
○ Sacrum
Center of gravity
● Point of a body about which all parts can be balanced
○ Apes: center of gravity is not over legs
○ Humans: center of gravity has to be over the legs
Features indicative of bipedality
● Foramen magnum
○ it is in the center of the skull for humans ○ Ifit’sinthebackthenitisanape
● Wedge shaped vertebrae
○ Curved in human vertebral column for shock absorption
● Short, broad pelvis, sacrum close to hip joints
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○ Broad pelvis= increases the size of the birth canal
● Very large gluteus maximus keeps humans from falling forward while running or walking ○
Orangutans have a lesser gluteus maximus
● Abductors- helps us keep balanced straight up
● Hominin femur is angled toward the midline (Bicondylar angle) which helps to maintain
balance over the foot
● Bicondylar angle develops from bipedal locomotion
● Large non- opposable big toe
● Short toes
● Large heel
● Presence of arches
● Large bones
○ Humans femur and tibia joints enlarged for weight transmission
○ If it's 90 degrees that individual had quadrupedal locomotion
○ Bipedal carry their weight on the ankles and knees
Canine size reduction
● No edge to edge sharpening of canines
● Upper lateral incisor and lower canine gap is called diastema
Earliest potential Hominins
● Sahelanthropus tchadensis - tiny brain, skull like apes
● Orrorin tugenensis - bipedal, curved fingers, less than one meter tall
● Ardipithecus kadabba- small brain, thin enamel, canines slightly reduced, bipedal
● Ardipithecus ramidus - 1st of the hominins, opposable toe, non- honing complex,
bipedal, small brain
Sahelanthropus tchadensis 6-7 mya
● Key features
○ Skull and teeth found
○ Tiny brain
○ Skull like apes - massive brow ridge Orrorin tugenensis - 6 mya
● Key features
○ Postcranial bones found
○ Femur indicates likely bipedality
○ Hand phalanx (fingers) likes apes (curved)- fingers are curved
○ Height: less than 1 meter tall
*what are the features we can say if a hominin is bipedal? Cortical bone thickness
Ardipithecus kadabba- 5.8 mya
● Key features
○ Skull, teeth, post cranial bones found
○ Small brain
○ Canine honing complex intermediate- canines are slightly reduced. They start to
develop the diamond shape
○ Thin enamel
○ Curved foot phalanges
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○ Femur and pelvis= capable of bipedalism
○ Less than 1 meter tall
○ Woodlands
Ardipithecus ramidus - first of the hominins 4.4 mya
● Key features
○ Skull, teeth, postcranial bones found
○ Small brain
○ No honing complex
○ Curved foot phalanges
○ Femur and pelvis= capable of bipedalism
○ 3.9 feet tall
○ Woodlands
○ Opposable toe
○ *what's unique among them? Opposable toe
Ardipithecus ramidus compared to pan (chimp)
● Head balanced on vertebral column
● Similar in brain size
● Less projecting face
● No canine- honing complex
● Small incisors
● Molar enamel intermediate between chimps and humans
● Body size dimorphism low (males and females are similar in body size)
● Femora angle towards midline - bipedal
● Hands with long fingers
● No knuckle walking features
● Short, broad pelvis
● Foot with divergent big toe
● More omnivorous than pan (which relies on fruit)
● Above branch crawling in trees
● Pelvic balancing not well- developed
Earliest Definite hominins- new topic
Definite hominins:
● Australopithecus anamensis
● *Australopithecus afarensis
● *Australopithecus africanus
● Australopithecus garhi
● Australopithecus sediba
Early hominins
“Gracile” Australopithecus
● Australopithecus afarensis (East Africa)
● Australopithecus africanus (South Africa) 2.4-3
Australopithecus afarensis- they have a fast life in every aspect “Lucy” and H. sapiens female
● Brains a little larger than pan (chimps) 400-500 cc
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● Sexual dimorphism
○ Male- 4’11, 99 lbs
○ Female- 3’5, 64 lbs 3.3 million years ago
Humans - first molars erupt at age 6-7 Human or chimp like*
● Dentally like a chimp
● Chimp- U- shaped teeth, diastema (gap between the lateral incisors and canine)
● A. afarensis- U-shaped teeth, diastema
● Human- parabolic shaped teeth, no diastema-
○ Distance of the shape increases. This feature came about after the genus Homo Sexual
Dimorphism in canines (males v. females)- canines more similar to humans
● Chimps- projecting forward
● A. afarensis- more diamond shape, cranial structure is wider than chimps
● Modern human- diamond shape
Primitive traits A. afarensis shares with living apes
● Brains a little larger than Pan: 4 00-500 cubic centimeters (cc)
● Projecting face
● U shaped teeth, Diastema
● Canines larger, more sexually dimorphic than in humans
2.8-3.8
● Asymmetrical premolars, not strongly bicuspid
● Broad cranial base, flat jaw joint
● Limbproportionsintermediatebetweenchimpanzeesandhumans(longarms,long
legs)- arm are longer than legs
● Long, curved fingers and toes
Derived skull traits in A. afarensis
● Canine reduction- canines are intermediate in size between pan (chimps) and Homo
● Premolars show slight development of second cusp
● Very large cheek teeth, thick enamel: heavy chewing, dietary shift towards harder to
process food
Laetoli, Tanzania: 3.6 mya footprints
● A. afarensis?
● Arches in the foot- flat feet would have trouble walking bipedally
● There were at least 70 hominin footprints
● Heel-strike followed by toe-off
● 3 individuals
● There were also foot prints of other animals
Derived Postcranial Features (Bipedality)
1. Foramen magnum underneath skull (to balance head on vertebral column)
● Bipedal locomotion leads to the foramen magnum underneath the skull
2. Vertebrae are wedge- shaped, giving spine shock absorbing curves
● Curves are important to walk bipedally
3. Sort, broad pelvis with sacrum near hip joints
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● But lesser gluteal muscles that are not wrapped around hip joint as much as in humans. Pelvis
balancing mechanism may not be fully developed
● Hominin- short, broad pelvis, sacrum close to hip joints
● Chimpanzee- tall pelvis. Sacrum far from hip joints
4. Femur is angled towards midline which maintains balance over one foot
● Hominins- toward midline
● Chimps- 90 degree angle
5. Femur and tibia joints enlarged for weight transmission
● Allows you to carry your weight efficiently
● Your weight is carried by your knees and ankles
6. Non-opposable big toe, arches in the foot
Australopithecus: improved bipedality compared to Ardipithecus, but are still climbing quite a bit
for feeding and sleeping
- Walks on the ground but still is involved in the arboreal environment Australopithecus africanus
- bigger brain and no diastema
● In general they reached milestones quickly Bipedal traits
● 1. Pelvis with iliac blades not as tall as those of chimps- wrap around nicely
● 2. Sacrum is broad from side to side and closer to hip joint (acetabulum)- reduced
compared to modern chimps
● 3. Femur with bicondylar angle (like humans)- tells us bipeds on the ground
● 4. Feet with non-divergent big toe (in line with the other toes)- similar to humans
Similar to Australopithecus afarensis
● Similar body size
● Similar degree of sexual dimorphism- males are larger than females
● U-shaped dental arcade- this is a primitive trait and is seen in all except the genus Homo
● Really long arms and long legs
● Infant development like Pan (chimp)
● Spent some time in trees
● Fast life in all aspects
Differences to Australopithecus afarensis (derived traits related to Australopithecus afarensis)
● Brain size is a bit larger than A. afarensis
● No diastema
● Face not as projecting
● Larger cheek teeth- larger molars and premolars due to dietary conditions
Australopithecus sediba
● Dental plaque- showed that they ate wood or bark
● Foot bones- similar to gorillas
● Compared to A. africanus-
○ Looks more modern
○ Face doesnt project as much
*********At approx. 2.5 mya
● 1. Gracile australopithecines disappear from East Africa
○ They will be replaced by the genus Homo and Paranthropus
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● Early Homo and 2. “robust Australopiths” (genus Paranthropus) appear
● 1st definite archaeological sites
○ New discovery: 3.3 mya... before genus Homo
● All are consequences of environmental changes in the late pliocene
● Only feature that's diff between australopithecines and the paranthropus is their
cranial features
East Africa:
● Habitat at 3 mya is very different than the habitat at 2.5 mya
● Because of environmental changes habitats changed
● Habitat at 2.5 mya- dry and open and forced to stay on the ground longer
******Early Hominins
● “robust” Australopiths- chewing machines 410-520 cc
○ Paranthropus aethiopicus (East Africa)
○ Paranthropus boisei (East Africa)
○ *Paranthropus robustus (South Africa)
● Earliest Homo
○ Homo habilis(“small” species)
○ Homo rudolfensis (“large” species)
Paranthropus
● The chewing machines of the hominins
● They have 2 huge muscles in their face/skull
● We have it smaller because we at softer foods
Paranthropus aethiopicus (East Africa)
● Has a high sagittal crest
● “Black skull”
Paranthropus boisei (East Africa)
● Olduvani Gorge, Tanzania
● They had huge premolars and molars→ molarized
South Africa:
Graciles vs Robusts (only applies for craniodental features)
● Temporal fossa
○ Australopithecus africanus- smaller temporal fossa, longer snout
○ Paranthropus robustus- larger temporal fossa, smaller snout
● Sagittal crest
○ Australopithecus africanus- no crest
○ Paranthropus robustus- sagittal crest in males
● Cheek bones
○ Australopithecus africanus- less robust zygomatics (cheek bones)
○ Paranthropus robustus- more robust zygomatics (cheek bones)
● Forehead
○ Australopithecus africanus- steeper
○ Paranthropus robustus- flatter
● Robustness of mandible (jaw)
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○ Australopithecus africanus- less
○ Paranthropus robustus- more
● Size/shape of premolars
○ Australopithecus africanus- small
○ Paranthropus robustus- molarized
“robust” Australopiths- chewing machines
● diet→ tubers- plants underground storage organs
○ They have the ability to eat things that are not their preferred food and therefore,
caused them to survive
● Brain size is a bit larger than A. afarensis
● Similar degree of sexual dimorphism to graciles. They are similar in body size
● U-shaped dental arcade
● *Premolars shaped like molars→ molarized molar - unique feature
● Tiny incisors and canines
● *Sagittal crest for huge temporal muscles - unique feature
● *who doesn't have a sagittal crest? Australopithecus
● May have used bone tools for termiting
○ *Bone tools→ they used bone tools to extract more food from the ground like termites
● Molar size increases are species develop → it tells you something about their diet. SA will
increase based on the food you are eating (hard foods).
Earliest Homo
● Homo habilis(“small” species)- cranium is small
● Homo rudolfensis (“large” species)- cranium is large
● Homo erectus- evolved in the african continent first and from homo habilis. They can
also cover distances
Homo:
● Shows up 2.8 mya
H. habilis cranial species - small
● “Handyman”
● First hominin species using stone tools
● Defining features:
○ It has a flat face which small
○ Forehead is rounded very nicely→ frontal area is developing much so compared to earlier
hominins
○ Back of the skull is very round
○ Small teeth
● All members of the genus homo have parabolic dental arcades → as you go back in
the mouth the distance between teeth is increasing
● Teeth look more intune with each other
● * footprint in latoliei had a little gap between the big toe and the rest and this IS
NOT the case for Homo
○ It's aligned with the rest of the toe
Homo rudolfensis cranial capacity - large
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● Defining features
○ Flat faces
○ Round cranium font and back
○ Inflated frontal area which fenals frontal brain developed largely
○ Slightly larger teeth than Homo habilis
*Early homo compared to other hominins:
● Flat faces
● Round cranium
● Smaller with teeth reduced in size
If you are living closer to 3 mya you are an australopithecus
Before 2.5 mya= australopithecus After 2.5 mya= Paranthropus Earliest Homo (1.6-2.8)
● Found in east and south africa
● Both have large brains compared to australopithecus
● Small form (H.habilis):
○ May have had an elongated femur
○ Used stone tools, may be ancestral to H. erectus
● Multiple hominins co existing
○ Paranthropus and Homo
Different adaptive strategies: d ifferent foods and dietary need
● Paranthropus: relying on at least seasonally on difficult process foods (low quality)
● Early H: at least seasonally (and perhaps year- round) eating high quality, nutritionally
dense foods like animals tissue
First stone tool:
● As early as 3.3 mya
● Oldowan industry
○ Simple core and flake tech
○ Useful for cutting and pounding
○ Appearance of tools coincident with first evidence of large mammal butchery
Range of african habitat types:
● Australopithecus will be in environments like woodlands that are very dense ex: distance from
tree to tree is very close
● Early homo will be in environments that are very open. Ex: distance from tree to tree is far
3.3- Homo erectus- new topic
*Who made the Oldowan tools?
● Homo habilis - evolved 2.8 mya
● *Homo erectus - evolved in africa at 1.9 mya
● *by 1.8 mya H.erectus already started conquering
H. erectus looks like H. habilis from kenya
● Homo erectus evolves from H. habilis
● Homo erectus is bigger than H. habilis
● Both taxa used tools and ate meat
● Homo erectus increased the meat consumption more than H. habilis
Homo erectus
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● Migrates out of africa after evolving
● Cranial morphology:
○ Increasing brain size capacity - increase in food products of high quality
○ Supraorbital torus
○ Round brain case
○ Flat faces
○ Occipital torus
○ Thick temporal lines but far apart
○ Snout is not sticking out (no more chimpanzee like nose)
● At 1.6 mya the “Turkana Boy” was found
○ About 8-9 years old when he died
○ He was about the height of a 13 year old human
○ H. erectus development was much faster than ours (shorter childhood period)
○ Age of first reproduction was 14.5
● The pelvis of the H. erectus
○ Pelvic blade wraps around sides the the body more than australopithecus
○ Pelvic balancing system better developed than Lucy
○ Birth canal is larger→ to pass babies with brains bigger than Australopithecus
babies
● Big brains= high quality diet
○ All homo species has high quality diets
○ Homo erectus
■ Large body and brain size
■ Reduced guts- in order to develop a larger brain you need to remove
energy from another body part system. They also aren't eating that much
plant material rather they are eating meat which is easier to digest
○ Nutrient dense foods
● Activity levels, thermoregulation
○ Thermoregulation like humans
■ Nose sticks out
■ Follow allen's rule
■ Humans sweating ability - hot adapted animals
○ Highly active
○ Human limb proportions
○ Long distance walker
○ Endurance running - outrun the prey
○ Bergmanns and Allen's rule
● Reproductive cost of big body and brain
○ Support system for reproductive females
■ Provide mom with resources
■ Provide resources to wean kids early
● Homo erectus out of africa
○ Dmanisi, Georgia is dated to 1.8 mya → is evidence that they left africa
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■ H. erectus was found here
■ First evidence out of Africa
■ Young individuals, females, males, and extremely old individuals
■ Perhaps they took care of their old individuals into the group
● They had severe arthritis which would require help from others in the group
● Homo erectus in asia
○ Zhoukoudian cave - They found H. erectus skulls here
● H. erectus from africa vs. H. erectus from asia
○ The ones from asia, their skull is more robust
○ Both brain case look like a football- elongated
● *Who made the Oldowan tools? Homo habilis
● First Hominin out of Africa
○ Homo ergaster- african specimens
○ Homo erectus- asian specimen
● Homo erectus at 1.6 mya
○ New stone tool tech called Acheulean culture
■ Producing this takes a lot of time, planning, and requires intelligence
○ Depending on where they are they will either use the Oldowan or Auchelean
○ Below the Movius line or above the Movius line they needed to adapt to that
environment (above the line they had more baboon tools Chopper- chopping
tools and able to make more tools)
● Auchelean tools
○ They were in africa, europe, and central and south asia
○ Known from about 1.6 mya
○ More technologically advanced= auchelean
○ Less advanced= chopper- chopping (oldowan) and baboon
● GBY
(gesher benot yaakov)
○ They had fire pits and burned things (cooking)
■ They found wood
■ Olive, wild grape, fruit seeds, and nuts
● H. erectus- The predator
○ Evidence of them being successful
■ Auchelean sites - hand axes
■ *Hypervitaminosis A
● When you have too much vitamin A its bad for you and the cortical bone becomes very thick
that it prevents the functioning of producing enough of RBC. maybe because they ate too much
liver
■ Tapeworms
● Based on molecular clock analysis, at 1.7 mya they become
present and we now have them today
● 3 species that infect humans most closely related to TW found in
hyenas, large cats and wild dogs
● Homo erectus lifeways
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○ Degree of sexual dimorphism is unclear, may have been reduced
○ Adapted to hot environment
○ Good with competing with other carnivore species
Homo heidelbergensis aka archaic humans
● They are more advanced
● They are found in the old world
○ First in africa, then europe and then in asia
● More robust brain case
Homo erectus vs. Homo heidelbergensis
● Similarities
○ Long, low skull
○ Thin brain case
○ Large brow ridges
○ Large faces
○ No chin
● Differences (derived features in H. heidelbergensis)
○ Bigger brain
○ Taller vault
○ Forehead more filled out
○ Double arched brow ridges
○ Back of skull is rounder
● H. erectus lasted longer in china
○ Disappeared from africa and europe
○ Found in china until 200,000 years ago
● Homo antecessor (Homo heidelbergensis)
○ Evidence of butchery marks on hominin remains
○ 32 individuals found
○ No individual is older than 35
○ Even gender ratio
○ Their lives were very tough and dying very early on
○ Were lives easier or harder?* harder
● Homo heidelbergensis
○ They were successful hunter- Used spears to kill megafauna Homo neanderthals
● They are eurasia species - found in europe and asia
● They are not found in africa
● Cold adapted species and they don't do well in warm species
● Pathological Elderly individual
○ Was taken care by others ■ Food sharing
■ Protections
● In reality they look “modern human like”
● Based on DNA they had red hair and blue eyes and the FOXP2 gene that gave them the
ability to speak
● Retual molar space- feature of a neanderthal
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● They have a large brain
● Compared to H. sapiens, neanderthals have
○ Wide pelvis
○ Thick-walled limb bones with large joint surfaces
○ Robust hand bones
○ Short forearms and shins
● Bergmann’s and Allen’s Rules
○ Broad chest, short forearms and shins minimize surface area/volume: cold
adaptation
○ Very large nose may be a cold adaptation too
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