Speciation and Evolution Concepts

These flashcards cover key vocabulary terms and concepts related to speciation and evolution as discussed in the lecture notes.

Speciation

The process of splitting one species into two or more new species, often involving changes in the gene pool.

Biological Species Concept

A species is defined as a group of populations that can interbreed and produce viable offspring, sharing a common gene pool.

Prezygotic Isolating Mechanisms

Factors that prevent mating or fertilization between species before the formation of a zygote.

Postzygotic Isolating Mechanisms

Factors that result in the failure of hybrid offspring to develop properly or to reproduce.

Allopatric Speciation

Speciation that occurs when a population is geographically separated, leading to the accumulation of genetic differences.

Sympatric Speciation

Speciation that occurs without geographic isolation, often due to genetic changes within a population.

Habitat Isolation

A type of prezygotic isolation where two species prefer different breeding habitats.

Temporal Isolation

A type of prezygotic isolation where species breed at different times, preventing interbreeding.

Behavioral Isolation

A type of prezygotic isolation that occurs when differences in mating behaviors prevent species from interbreeding.

Mechanical Isolation

A type of prezygotic isolation where structural differences in reproductive organs prevent mating.

Gamete Isolation

A type of prezygotic isolation that occurs when gametes (sperm and egg) from different species are prevented from fertilizing each other.

Hybrid Sterility

A condition where the hybrid offspring of two different species are sterile and cannot reproduce.

F2 Fitness

The fitness of the second generation offspring (F2) of a hybrid, which may be weak or unable to reproduce.

Hybrid Zone

An area where two genetically distinct populations meet and interbreed, creating hybrids.

Continental Drift

The movement of the Earth's continents, which can lead to geographical barriers and contribute to speciation.

Gene Pool Changes

Alterations in the genetic composition of a population, often leading to speciation.

Speciation Event

An occurrence in which a lineage splits into two or more genetically distinct species.

Abiotic Factors

Non-living chemical and physical parts of the environment that affect living organisms.

Biotic Factors

Living components of the environment that influence the interactions and survival of species.