Introduction to Evolution

Flashcards for studying key concepts related to evolution, including definitions and explanations of terms discussed in the lecture.

Evolution is defined as a change in __ frequencies within a population over time.

allele

Fitness is the ability of an individual to produce __, __ offspring relative to others in the population.

surviving, fertile

A __ is a heritable trait that increases an individual’s fitness in a particular environment.

adaptation

Natural selection acts on __, but only populations evolve.

individuals

In __ thinking, species are viewed as fixed, perfect, and unchanging types.

typological

The process of natural selection includes individuals in a population varying in their traits, where some traits are __.

heritable

Darwin’s theory of evolution emphasizes that evolution is not __ or necessarily progressive.

linear

The fossil record provides evidence that species are not __ and that they are all related.

unchanging

A __ trait is reduced or nonfunctional and is homologous to a functional trait in related species.

vestigial

Heritable traits that increase reproductive success can include all and traits.

physiological, behavioral

Genetic drift is a __ change in allele frequencies most impactful in small populations.

random

Horizontal gene transfer can introduce novel __ and increase variation.

traits

Natural selection __ the average trait value in one direction during directional selection.

shifts

In __ selection, individuals with extreme traits are favored and intermediates are removed.

disruptive

Cuticle is a structural adaptation in land plants that prevents __ loss.

water

The Great Oxidation Event was triggered by the evolution of __ photosynthesis by cyanobacteria.

oxygenic

Gymnosperms evolved key adaptations such as __ and seeds that allowed them to thrive in dry environments.

pollen

The evolution of land plants required adaptations to solve challenges such as __ transport and reproduction without water.

nutrient

Evolutionary adaptations such as bipedalism and larger brains in humans evolved in a __ fashion.

stepwise

In sexual selection, __ selection occurs when one sex chooses mates based on traits like coloration or courtship.

intersexual