What are the current numbers for populations of polar bears, walruses, bowhead whales, and ringed seals in the arctic? How accurate is the data available any how do researcher feel about the lack of data? cite all resources in-text

In a graph of population size versus time, a J-shaped curve is characteristic of (a) exponential population growth (b) logistic population growth (c) zero population growth (d) replacement-level fertility (e) population growth momentum

David Hills of Baylor University noted that three closely related species of leopard frog (genus Rana) exhibit substantialbut not completepostzygotic reproductive isolation when crossed in the laboratory. Field surveys of numerous populations in Texas and surrounding states revealed that populations of the three species breed at various times during the year. Data on the breeding schedule of both allopatric and sympatric populations of these species are presented in the Figure below. Interpret the data in the figure and explain how they may demonstrate that these frogs experience prezygotic reproductive isolation in nature. What type of prezygotic reproductive isolation do the data suggest? Source: D.M. Hillis. 1981. Premating isolating mechanisms among three species of the Rana pipiens complex in Texas and southern Oklahoma. Copeia 1981:312-319.

The largest population that can be maintained by a particular environment for an indefinite period is known as a (a) semelparous population (b) population undergoing exponential growth (c) metapopulation (d) populations carrying capacity (e) source population

Figure 19.6 If the major food source of seals declines due to pollution or overfishing, which of the following would likely occur? a. The carrying capacity of seals would decrease, as would the seal population. b. The carrying capacity of seals would decrease, but the seal population would remain the same. c. The number of seal deaths would increase, but the number of births would also increase, so the population size would remain the same. d. The carrying capacity of seals would remain the same, but the population of seals would decrease.

A population of 1,000 individuals experiences 462 births and 380 deaths in 1 year. What is the value of r for this population? a. 0.842/individual/year b. 0.462/individual/year c. 0.380/individual/year d. 0.820/individual/year e. 0.082/individual/year

The CDC released the following data in its 2013 Vital Statistics report. Age interval Number dying in age interval Number surviving at beginning of age interval 0-10 756 100,000 11-20 292 99,244 21-30 390 98,953 31-40 1,234 98,164 41-50 2,457 96,311 51-60 5,564 94,352 61-70 10,479 38,788 Table 45.3 Calculate the mortality rate for each age interval, and describe the trends in adult and childhood mortality per 100,000 births in the United States in 2013.

Figure 1.15 Example of error bars in a graph. This graph was adapted from the peacock butterfly research described in Section 1.5. The researchers recorded the number of times each butterfly flicked its wings in response to an attack by a bird. The squares represent average frequency of wing flicking for each sample set of butterflies. The error bars that extend above and below the dots indicate the range of valuesthe sampling error. Figure It Out: What was the fastest rate at which a butterfly with no spots or sound flicked its wings?

Primates are examples of: density-dependent species density-independent species r-selected species K-selected species

_______________ competition occurs within a population, and _______________ competition occurs among populations of different species. (a) Interspecific; intraspecific (b) Intraspecific; interspecific (c) Type I survivorship; Type II survivorship (d) Interference; exploitation (e) Exploitation; interference