1. In an experiment, suppose that the wings of fruit flies were clipped short for fifty generations. The fifty-first generation emerged with normal-length wings. This observation would tend to disprove the idea that evolution is based on
   

Ainheritance of natural variations

Binheritance of acquired characteristics

Cnatural selection

Dsurvival of the fittest

1. Charles Darwin called the ability of an organism to survive and reproduce in its specific environment
   

Adiversity

Bfitness

Cadaption

Devolution

1. Similar patterns of embryological development in different but related organisms are responsible for the formation of
   

Ahomologous structures

Banalogous structures

CHox genes

Dintermediate fossil forms

1. If an allele makes up one half of the frequency of a population's allele for a given trait, its allele frequency is
   

A100 percent

B75 percent

C50 percent

D4 percent

1. The frequency of phenotypes for a typical polygenic trait is most often illustrated as
   

Aa scatter plot

Ba bell-shaped curve

Ca pie chart

Da histogram

1. Which of the following events do biologists consider a random change?
   

Adirectional selection

Bspeciation

Cdisruptive selection

Dgenetic drift

1. Which of the following statements defines the members of a species?
   

AThey are temporarily isolated from each other

BThe are geographically isolated from each other

CThey mate and produce offspring

DThey have identical genes