Small populations of organisms are less likely to survive changes in the environment becauseA.individuals cannot find mates in such small populations.B.mutations do not occur in small populations.C.there is not sufficient variation in the gene pool of the population to ensure that some members are better adapted in the new environment.D.natural selection only applies to very large populations.

Organisms that are more adapted to their environment are more likely to survive and pass on the genes that aided their success. This process causes species to change and diverge over time.

Why is it that some organisms do not appear to be perfectly adapted to their environment?Multiple choice question.Because natural selection always proceeds from simpler to more complex organisms and as complexity increases, adaptation becomes more difficult.Because natural selection can only work on the variation present in a population.Because humans have influenced the evolution of almost all living things by artificial selection, making some of them less adapted.

Which of these conditions should completely prevent the occurrence of natural selection in a population over time?Group of answer choicesThe environment is changing at a relatively slow rate.All variation between individuals is due only to environmental factors.The population lives in a habitat where there are no competing species present.The population size is large.

Which of the following is least likely to cause a species to become extinct due to changes in the environment?Group of answer choicesless genetic variation within the speciesspecific food preferencesmore competition for foodmore genetic variation within the species

.Mutations must occur in gametes in order to be passed onto offspring.b.Most mutations do not result in a phenotype that increases the individual's fitness.c.Mutations occur very rarely in organisms.d.All mutations are harmful.e.Mutations decrease genetic variation in a population.