Iguana Decline In 1987, Martin Wikelski began a long-term study of marine iguanas in the Calapágos Islands. He marked iguanas on two islands—Genovesa and Santa Fe—and collected data on how their body size, survival, and reproductive rates varied over time. He found that because iguanas eat algae and have no predators, deaths usually result from food shortages, disease, or old age. In January 2001, an oil tanker ran aground and leaked a small amount of oil into the waters near Santa Fe. FIGURE 44.17 shows the number of marked iguanas that Wikelski and his team counted in their study populations just before the spill and about a year later.
FIGURE 44.17 Shifting numbers of marked marine iguanas on two Galápagos islands. An oil spill occurred near Santa Fe just after the January 2001 census (orange bars). A second census was carried out in December 2001 (green bars).
3. Wikelski concluded that changes on Santa He were the result of the oil spill, rather than sea temperature or other climate factors common to both islands. How would the census numbers be different from those he observed if an adverse event had affected both Islands?
Want to see the full answer?
Check out a sample textbook solutionChapter 44 Solutions
Bundle: Biology: The Unity and Diversity of Life, Loose-leaf Version, 14th + LMS Integrated for MindTap Biology, 2 terms (12 months) Printed Access Card
- Which of these following scenarios is caused by the Allee effect? Corals rely on external fertilization when gametes (sperm and eggs) are released into the sea in large quantities and have to meet at random chance. When coral densities drop due to coral bleaching and die back, external fertilization becomes inefficient, few zygotes form, and coral populations further decline or go extinct. After a big disturbance in forests, such as fire, many seeds germinate and seedlings compete for space, light and resources. K-selected species produce fewer, but larger seeds that are initially outnumbered by the numerous sEeds and resulting seedlings of r-selected species. The initial advantage of r-selected species of Occupying more locations and therefore by random chance also better locations, is later overcome by the K-selected species higher competitive ability. Therefore, for the first years to decades, r-selected species dominate areas that experienced severe disturbances, while in mature…arrow_forwardYou are surveying of the turtle species identifies several breeding populations in different habitats across the island. After a very warm summer of 2020, you observe that the hatchlings from low-elevation nests are mostly males, whereas hatchlings from higher elevations have an equal female-to-male sex ratio. As a bit more background, temperature influences the sex ratio in some turtle species, a phenomenon called temperature-sex determination (TSD). With this knowledge, you hypothesize this new turtle species exhibits TSD, and that eggs incubated at low elevations during the warm year experienced a high enough embryonic temperature to skew the sex ratio. To test this, you collect 20 newly laid eggs in early 2021 & take them back to the lab to conduct an experiment to test your hypothesis that this species exhibits TSD. Assume you know the average nest temperature in the wild, and you have access to multiple incubators Design an experiment to test the hypothesis that this turtle…arrow_forwardIn spadefoot toads there are two forms of the tadpoles: omnivores and carnivores. Environmental factors such as population density, oxygen concentration, and availability of food determine which form any particular tadpole takes. Consider the situation below. A single pair of toads produces a fertilized group of eggs in a pond. The pond dries a bit creating two separate ponds, one is deep and the other is shallow. All the tadpoles in the deep pond become omnivores and all the tadpoles in the deep pond become carnivores. There is a heavy rain and the ponds become connected again and the two groups of tadpoles mix together. The carnivores eat most of the omnivores and more of the carnivores become adult toads This is an example of Group of answer choices A. natural selection and evolution B. evolution only C. natural selection onlyarrow_forward
- Iguana Decline In 1987, Martin Wikelski began a long-term study of marine iguanas in the Galpagos Islands. He marked iguanas on two islandsGenovesa and Santa Feand collected data on how their body size, survival, and reproductive rates varied over time. He found that because iguanas eat algae and have no predators, deaths usually result from food shortages, disease, or old age. In January 2001, an oil tanker ran aground and leaked a small amount of oil into the waters near Santa Fe. FIGURE 44.3 shows the number of marked iguanas that Wikelski and his team counted in their study populations just before the spill and about a year later. FIGURE 44.3 Shifting numbers of marked marine iguanas on two Galpagos islands. An oil spill occurred near Santa Fe just after the January 2001 census (orange bars). A second census was carried out in December 2001 (green bars). How much did the population size on each island change between the first and second census?arrow_forwardIguana Decline In 1987, Martin Wikelski began a long-term study of marine iguanas in the Galpagos Islands. He marked iguanas on two islandsGenovesa and Santa Feand collected data on how their body size, survival, and reproductive rates varied over time. He found that because iguanas eat algae and have no predators, deaths usually result from food shortages, disease, or old age. In January 2001, an oil tanker ran aground and leaked a small amount of oil into the waters near Santa Fe. FIGURE 44.3 shows the number of marked iguanas that Wikelski and his team counted in their study populations just before the spill and about a year later. FIGURE 44.3 Shifting numbers of marked marine iguanas on two Galpagos islands. An oil spill occurred near Santa Fe just after the January 2001 census (orange bars). A second census was carried out in December 2001 (green bars). Wikelski concluded that changes on Santa Fe were the result of the oil spill, rather than sea temperature or other climate factors common to both islands. How would the census numbers be different from those he observed if an adverse event had affected both islands?arrow_forwardHow would this unusual reproductive behavior benefit these small fish?arrow_forward
- Use the survivorship curves (A, B, and C) shown on the graph below to answer the following three questions. kx A B с Age Which curve best describes survivorship in clams? (Clams have external fertilization and free-swimming larval stages.) Curve A Which curve best describes survivorship in mice? Curve C Which curve best describes survivorship in a species, such as humans, that invests a great deal in caring for the young over a very long period of time? Curve Barrow_forwardLooking at Figure 1 above, do locations that have a history of Paralytic Shellfish Poisoning typically have a population with a higher frequency of sensitive or resistant clams? Speculate as to why.arrow_forwardWhy are frogs a good indicator species? They are increasing in number, suggesting that they are resistant to environmental degradation. They are resistant to increases in ultraviolet light. They are of considerable economic importance. Their numbers can be manipulated easily with minimal effects on other species. Their eggs do not have hard shells to protect them from environmental contaminants.arrow_forward
- Can you answer all the parts to this question Anadromous- born in freshwater, migrate to saltwaterCatadromous- born in saltwater, migrate to freshwaterOceanodromous- born in saltwater body, migrate to another saltwater bodyPotamodromous- born in freshwater stream or lake, migrate to another stream or lake Example of one anadromous species? And what is its migration pattern? (as in what specific bodies of water does this specimen breed in and live in?) Example of one catadromous species from your list? And what is its migration pattern? (as in what specific bodies of water does this specimen breed in and live in?)arrow_forwardWhat about a sperm whale's blow hole as an adaption ensures their oceanic survival? Fully cite and use recent peer reviewed sources from 2010 to the present.arrow_forwardA scientist for one of the Water Management Districts near Victoria conducts a study of the effects of industrial wastewater on marine clams (animals that are sessile as adults) by comparing the density and reproductive condition of clams collected within 100 m of a discharge pipe with those collected 10 km away. He found very low densities of clams near the pipe and those that were there had very small gonads. You have been hired by the company discharging wastewater via this pipe to explain why these data should not be used to shut you down. What scientific arguments are you going to make to the review board? Hint: don’t talk about study design issues….tell me about what other ecological factors might be at play here.arrow_forward
- Biology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781337408332Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage LearningBiology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781305073951Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage LearningBiology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning