BIOL 240 Exam 1 Review

Flashcards for BIOL 240 Exam 1 focusing on key vocabulary and concepts related to evolution and natural selection.

Stabilizing selection

A pattern in which traits tend to remain the same over time, maintaining a stable form.

Punctuated equilibrium

A concept in evolutionary biology where evolution is characterized by long periods of stability interrupted by brief periods of significant change.

Disruptive selection

A type of natural selection that favors individuals with extreme phenotypes over those with intermediate phenotypes.

Prezygotic isolation

A form of reproductive isolation that occurs before the formation of a zygote, often due to mating preferences.

Plasticity

The ability of an organism to change its phenotype in response to environmental conditions without changes in genotype.

Homology

The existence of shared ancestry between a pair of structures or genes in different taxa.

Convergent evolution

The independent evolution of similar traits in species of different lineages.

Evolution

Changes in allele frequencies in a population over time.

Typological species concept

A definition of species based on morphological similarity, without regard to genetic or reproductive differences.

Biological species concept

A definition of species based on the ability of individuals to reproduce and form viable offspring.

Monophyletic group

A group of organisms that includes an ancestor and all its descendants.

Synapomorphy

A derived trait that is shared by a group of organisms and is used to define a clade.

Symplesiomorphy

An ancestral trait shared by two or more groups but found in other groups as well.

Natural selection

The process by which traits that improve survival and reproduction become more common in a population.

Context-dependent fitness

The idea that the relative fitness of traits can vary depending on environmental conditions.

Neutral mutations

Mutations that do not affect an organism's fitness and thus do not influence natural selection.

Asexual reproduction

A mode of reproduction where offspring are produced by a single parent without the fusion of gametes.

Sexual reproduction

A mode of reproduction involving the combining of genetic material from two parents.

Two-fold advantage of asexual reproduction

The concept that asexual reproduction allows for all genes to be passed on to offspring, unlike sexual reproduction, where only half are inherited.

Kin selection

A form of natural selection that considers the role of relatives in the evolutionary success of an organism.