Phylogeny, Speciation, and Life

These flashcards cover essential vocabulary related to phylogeny and speciation, focusing on definitions that are crucial for understanding evolutionary biology concepts.

Phylogeny

The study of the evolutionary history and relationships among individuals or groups of organisms.

Speciation

The process through which new species arise, often due to genetic isolation and divergence of populations.

Allopatry

A form of speciation that occurs when populations are geographically isolated from one another.

Sympatry

Speciation that occurs when populations live in the same geographical area but evolve separately.

Binomial Nomenclature

The formal system of naming species by a two-part name consisting of the genus and the species identifier.

Linnaean System of Classification

A hierarchical system for classifying organisms into categories such as domain, kingdom, phylum, class, order, family, genus, and species.

Biological Species Concept

Defines species as groups of actually or potentially interbreeding populations that are reproductively isolated from other such groups.

Morphospecies Concept

Defines species based on their morphological characteristics, often used when data on gene flow is unavailable.

Phylogenetic Species Concept

Defines species as the smallest monophyletic group on a phylogenetic tree, based on common ancestry.

Adaptive Radiation

The rapid diversification of a lineage into a wide variety of forms to adapt to different environments or niches.

Reproductive Isolation

Mechanisms that prevent species from interbreeding and producing viable offspring, categorized as prezygotic or postzygotic.

Vicariance

A process of speciation that occurs when a geographical barrier arises, splitting a population into two or more distinct groups.

Dispersal

The movement of individuals from one location to another, which can initiate speciation.

Niche

The role or function of an organism or species within an ecosystem, including its resource utilization and conditions tolerated.

Hybridization

The mating of individuals from different species or lineages, leading to hybrid offspring.

Cryptic Species

Species that are morphologically indistinguishable but genetically distinct.

Polymorphism

The occurrence of two or more different forms among the members of a population.

Gene Flow

The transfer of genetic material between populations, which can counteract the effects of speciation.