Chapter 4: Evolution — Natural Selection Vocabulary

Vocabulary study guide flashcards covering key definitions, mechanisms, constraints, and historical figures from Chapter 4 on Evolution and Natural Selection.

Evolution

A change in the genetic composition (allele frequencies) of a population over time.

Biological fitness

The ability of an individual to produce surviving, fertile offspring relative to other individuals in the population.

Adaptation

A heritable trait that increases an individual's fitness in a particular environment relative to individuals lacking that trait.

Acclimatization

A change occurring during an individual's lifetime, often caused by environmental conditions, that does not involve genetic change.

Fitness trade-off

A scenario occurring when an organism cannot maximize two traits simultaneously, meaning a trait can be advantageous in one situation while carrying a cost in another.

Genetic correlation

A genetic constraint occurring when one gene influences multiple traits, causing selection on one trait to change another trait as well.

Historical constraints

Limitations on evolution resulting from natural selection working with structures inherited from ancestors rather than starting from scratch.

Gene flow

The movement of alleles between populations.

Genetic drift

Random changes in allele frequency within a population.

Mutation

A chance event that serves as the ultimate source of new alleles.

Heritability

The state where trait differences have a genetic basis and can be passed from parents to offspring.

Differential reproductive success

The phenomenon where individuals in a population do not all survive and reproduce equally.

Population

A group of individuals of the same species living in the same place at the same time.

rpoB gene

A gene in Mycobacterium tuberculosis in which a chance mutation can confer resistance to the antibiotic rifampin.

Charles Darwin

A naturalist (1809–1882) aboard the H.M.S. Beagle during its 1831–1836 voyage who studied organisms and variation in nature and independently developed the theory of natural selection.

Alfred Russel Wallace

A naturalist (1823–1913) who collected tropical species and independently developed the idea of natural selection in the mid-1800s.

Biston betularia

The scientific species name for the peppered moth, which shows variation in wing coloration between light and dark individuals.