Chapter 24: The Origin of Species Answers EVEN

2)  Adult chimpanzees have heavier brow ridges.

 4relative small genetic change can have a major impact on phenotype. 

 6)  it is not possible to test reproductive isolation in fossil forms. 

 8) The two forms are observed to interbreed successfully where their habitats overlap. 

 10Gene flow between the two populations is extensive. 

 12)  gametic incompatibility

 14) speciation

 16)  They shared a common ancestor recently in evolutionary time.

 18)  3 and 5

 20) morphological

22)  habitat isolation

 e 24)  two species of orchids with different floral anatomy

 c 26)  two species of meadowlarks with different mating songs 

 b 28)  two species of pine shed their pollen at different times

 30) soils

 32)  reinforce postzygotic barriers between horses and donkeys.

 34)  III only

 36) the islands are very young in geologic time.

 38) polyploidy.

 40)  meiosis.

 42)  14.

 44) geographic isolation. 

46) speciation occurred rapidly in geologic time.

 48 A new species forms most of its unique features as it comes into existence and then changes little for the duration of its existence.

 50)  sympatric speciation.

52) ancestral versions of this protein assemblage were either less functional, or had different functions, than modern prokaryotic flagella.

54) a change in a regulatory gene, which has a major and adaptive impact on morphology

 56)  in particular environments, similar adaptations can be beneficial in more than one species.