Macroevolution Study Set

A vocabulary-focused flashcard set to help in studying key concepts related to macroevolution.

Macroevolution

Gradual adaptation of a population to its environment.

Microevolution

Small changes in allele frequencies within a population over generations.

Speciation

Formation of new species when one lineage splits into two.

Ecological Species Concept

Species defined by their niche.

Phylogenetic Species Concept

Species defined by DNA and evolutionary history.

Biological Species Concept

Species = groups that can mate & produce fertile offspring.

Morphological Species Concept

Species identified by appearance and structure.

Reproductive Isolation

Barriers preventing mating between species.

Prezygotic Barriers

Prevent mating/fertilization before a zygote forms.

Postzygotic Barriers

Problems occur after fertilization.

Mechanical Isolation

Reproductive parts don’t fit.

Gametic Isolation

Gametes can’t fuse due to incompatibility.

Hybrid Sterility

Hybrid offspring are sterile and cannot reproduce.

Adaptive Radiation

One ancestor rapidly diversifies into many species in new niches.

Allopatric Speciation

Speciation due to geographic isolation.

Sympatric Speciation

Speciation without geographic separation.

Sexual Selection

More than two chromosome sets; common in plants.

Hybrid Zone

Region where two species meet & produce hybrids.

Punctuated Equilibrium

Long periods of no change with bursts of rapid evolution.

Gradualism

Slow, steady evolution.

Exaptation

Structure evolves for one use, later used for another.

Hox Genes

Control major body patterning.

Paedomorphosis

Adult keeps juvenile traits.

Mass Extinction

A large, sudden drop in biodiversity.

Permian Extinction

A major extinction event caused by extreme conditions.

Cretaceous Extinction

Extinction event leading to the demise of dinosaurs.