Which of the following statements is true of microevolution? (Select all that apply.)
a. It is a change in allele frequency within populations.
b. It is caused by inheritance of characters acquired during the life of an organism.
c. It is only seen when some allelic variants cause individuals to have increased reproductive success.
d. It always leads to adaptation.
e. It is caused only by natural selection.
Adv.
When occurs inside the population within a short time period, it is termed as microevolution. Here, no new species are formed. Only slight modifications occur in the allele frequency of the individual organisms. For example, an organism inherits a particular phenotype characteristic from its parents, which helps it to defend itself from predators. The organism, in turn, lives longer and produces more offspring. The alleles, responsible for this phenotype character will be passed to its entire offspring. So, within a short time period, majority of these organisms would be having that particular phenotype characteristic. This alteration in frequency of allele, inside the population is called microevolution.
Hence, the correct option is (a) It is a change in allele frequency within populations.
Match the agent of microevolution to its description:
| a. mutation | chance alterations of allele frequencies, having the greatest effect on small populations |
| b. gene flow | a process through which traits that confer a reproductive advantage to individuals are seen with greater frequency in succeeding generations of a population |
| c. natural selection | movement of alleles between populations by migration |
| d. genetic drift | genetic drift brought about by migration of a subpopulation |
| e. founder effect | changes in the genetic material |