A.   all of these are essential elements of natural selection.

B.   individuals with useful adaptations will be more likely to survive and reproduce.

C.   while organisms within a population reproduce rapidly, resources are limited.

D.   individuals within a population vary.

A.   the struggle for existance.

B.   Natural selection is based on all three of these answers.

C.   the inheritance of variation.

D.   variation in fitness.

A.   there are no differences in the traits to be favored and affect survival and reproducation.

B.   there is no competition.

C.   traits are not inherited by offspring.

D.   evolutionary change would proceed in a nonadaptive direction.

A.   cannot be passed from parent to offspring.

B.   almost always occur by chance alone.

C.   are components of organisms that enable them to survive and reproduce.

D.   allow organisms to evolve more rapidly.

A.   stabilizing selection

B.   disruptive selection

C.   directional selection

D.   averaging selection

A.   changed because equilibrium existed in the population

B.   never changed because of stasis

C.   changed over time because of environmental change

D.   never changed because of high juvenile mortality

A.   the survivors of the drought had a larger average beak size

B.   a large number of the birds had died as a result of the drought

C.   The Grants found all these things as part of their study.

D.   beak size is inherited so the next generation had a larger average beak size

A.   mendelian trait

B.   polygenic trait

C.   non-genetic trait

D.   dominant trait

A.   Chromosomes come in pairs.

B.   One chromosome from each homologous pair is passed on to gametic cells during meiosis.

C.   Hereditary material is contained in the chromosomes.

D.   These are all true about choromsomes

A.   allele

B.   gene

C.   mutation

D.   genetic drift

A.   were discovered by Darwin.

B.   the somatic cells of the body.

C.   the sex cells or eggs and sperm.

D.   do not differ between male and female animals.

A.   All of these are ways that genetic variation remains within a population.

B.   There is no blending during sexual reproduction.

C.   New variation is slowly added by mutation.

D.   Mutations can be hidden in the heterozygous genotype.

A.   mutation

B.   natural selection

C.   genetic drift

D.   migration

A.   all of these are important in shaping continuously varying traits

B.   can be greatly impacted by the environment during an individual's growth and development.

C.   are affected by genes at many loci.

D.   are shaped by many genes, each with only a small effect on the phenotype.

A.   recombination

B.   migration

C.   mutation

D.   genetic drift

A.   populations out of equilibrium.

B.   small populations.

C.   medium-sized populations.

D.   large populations.

A.   maladaptive changes in gene frequencies.

B.   changes in gene frequencies that are random with respect to adaptation.

C.   adaptive changes in gene frequencies.

D.   equilibrium in genetic frequencies.

A.   the differential reproductive success of individuals

B.   the chance loss of alleles in a population

C.   the exchange of genes between populations

D.   the production of new genetic material

A.   mutation

B.   genetic drift

C.   All of these forces may disrupt equilibrium.

D.   gene flow

A.   any type of genetic mutation

B.   the change in allele frequencies from one generation to the next

C.   the change from one species to another in one generation

D.   the appearance of new species

A.   the extinction of a species.

B.   the formation of new species.

C.   evolutionary change within a species.

D.   the death of individuals in a group.

A.   the relationship between humans and other animals in their ecological niche

B.   how the evolution of one species affects the evolution of another species

C.   small scale evolutionary changes within a single generation

D.   large scale evolutionary change such as speciation

A.   migration

B.   allopatric speciation.

C.   extinction

D.   sympatric speciation.

A.   parallel evolution.

B.   generalization.

C.   homology.

D.   adaptive radiation.

A.   genetic drift within populations.

B.   they way natural selection favors particular traits suited to a specific ecological niche.

C.   gene flow among members of the same species.

D.   sexual selection between two different species

A.   natural selection is a powerful process.

B.   gene flow between individuals within the population keeps them similar to each other.

C.   environments change slowly.

D.   new mutations are usually maladaptive.

A.   punctuated equilibrium.

B.   parallel evolution.

C.   gradualism.

D.   microevolution.

A.   one possible explanation of speciation accepted by biologists today, is not the only pattern of speciation observed in the natural world and is called the theory of phyletic gradualism.

B.   is called the theory of phyletic gradualism.

C.   one possible explanation of speciation accepted by biologists today.

D.   is not the only pattern of speciation observed in the natural world.

A.   when interbreeding between two different species results in less successful hybrid offspring.

B.   males and females don't like each other very much and so prefer not to mate.

C.   because there is over-population and species survival depends on a new species evolving.

D.   when there is extensive gene flow within a single species.