Chapter 22: Descent with Modification: Answers

1) morphology and anatomy

2) the fossil record.

3) body with Earth

4) Earth is 6,000 years old, and populations are unchanging.

5) Characteristics acquired during an organism's life are generally not passed on through genes.

6) Variations in the development of the structures occur as the embryos grow.

7) an overarching explanation, supported by much evidence, for how populations change over time.

8) Charles Lyell

9) biogeography.

10) Alfred Wallace

11) a mechanism for evolution that was supported by evidence.

12) more recently they shared a common ancestor.

13) The interaction of organisms with their environment is important in the evolutionary process.

14) individuals must adapt to their environment.

15) Populations tend to increase at a faster rate than their food supply.

16) island forms and mainland forms descended from common ancestors.

17) 2, 4, 1, 3

18) by identifying the bones as being homologous by proposing that humans, bats, and dolphins share a common ancestor

19) back and knee problems.

20) baleen whales are descendants of toothed whales.

21) All organisms use essentially the same genetic code.

22) DNA or RNA analysis

23) DNA sequence evidence fully disagreed with morphological evidence.

24) The amount of available food may have increased. The number of predators may have decreased. The squirrels of subsequent generations should show greater levels of variation than previous generations because squirrels that would not have survived in the past will now survive.

25) A number of genetically resistant pesticide survivors reproduce. The next generation of insects contains more genes from the survivors than it does from susceptible individuals.

26) Of the following anatomical structures, which is homologous to the wing of a bat?

arm of a human