BIOL 101: Lecture #5 Flashcards

Vocabulary flashcards based on the 8/30/20 lecture notes covering macroevolution, speciation, and adaptive radiation.

Macroevolution

Large-scale evolution of phenotypes, like the formation of new species or major changes in body structure.

Species (Biological Definition)

A group of organisms that can reproduce with each other and produce fertile offspring.

Species (Morphological Definition)

A group of organisms that share similar physical traits and characteristics.

Species (Ecological Definition)

A group of organisms that occupy a similar niche or role in their environment.

Species (Phylogenetic Definition)

A group of organisms that are closely related to one another based on their evolutionary history.

Phenotype

The observable characteristics or traits of an organism, such as its appearance, behavior, or physiology.

Genotype

The genetic makeup of an organism that determines its phenotype; the specific genes or DNA sequences that code for a particular trait.

Speciation

The process by which one species splits into two or more distinct species over time.

Reproductive Isolation

Barriers that prevent different species from interbreeding, thus keeping their gene pools separate.

Prezygotic Barriers

Reproductive barriers that occur before the formation of a zygote (fertilized egg), such as differences in mating rituals or habitats.

Postzygotic Barriers

Reproductive barriers that occur after the formation of a zygote, such as the offspring being infertile or unable to survive.

Hybrids

Offspring resulting from the interbreeding of two distinct species.

Allopatric Speciation

The formation of new species when populations are geographically separated, preventing gene flow between them.

Sympatric Speciation

The formation of new species when populations live in the same geographic area.

Polyploidy

A condition in which cells have more than two sets of chromosomes, which can lead to rapid speciation in plants.

Niche

The specific role an organism plays in its environment, including its habitat, food sources, and interactions with other species.

Adaptive Radiation

The rapid diversification of a single ancestral species into many new species, often when colonizing new environments or after a mass extinction event.

Gradual Speciation

The process by which species diverge slowly and steadily over long periods.

Punctuated Equilibrium

A pattern of evolution in which long periods of stasis (little or no change) are interrupted by short bursts of rapid change.

Sexual Selection

A form of natural selection in which individuals with certain traits are more likely to attract mates and reproduce.