Mutation is the only mechanism of evolution that:

How does natural selection affect the frequency of mutations?

In the phylogeny below, note the following variations: -Body size (large or small) -Number of arms (3, 4, or 5 arms) -Body coloration (spotted, striped, or solid)   Which trait(s) evolved at position #1? Select the one best answer.

Evolutionary processes cannot:

A predator is introduced that removes only the smallest individuals from a population.  In this case, ____ is acting.

HARDY-WEINBERG CALCULATIONS: In a population of gorillas, there are two alleles at a particular locus (G and g), and the frequency of the dominant G allele is 0.1.  What is the expected frequency of heterozygotes under the Hardy-Weinberg equilibrium model? 

Which of the following statements about the Hardy-Weinberg equilibrium is FALSE?

Imagine that, decades ago, a researcher studying a population of moths found that antennae length ranged from 4.6 mm to 7.8 mm, with an average length of 6.1 mm.  Today, you are studying the same population of moths and find that the average antenna length is 6.1 mm, with a range of 5.2 mm to 6.7 mm.  Which statement best explains your results?

FILL-IN: In the phylogeny above, the taxa A, B, C, D, E, and F represent a (n) __________ group (also called a clade), consisting of the common ancestor and all descendant taxa.  Spell carefully.

A tsunami kills most of a hermit crab population but there are a few survivors.  Several of them have unusually wide claws on their front legs.  Several generations later, the hermit crab population has grown large again but the claw width is larger than in the original population.  Which of the following best describes this scenario?