Evolutionary Biology Concepts

These flashcards cover key concepts in evolutionary biology, including definitions of important terms related to natural selection, heredity, and phylogenetic analysis.

Pangenesis

Darwin's incorrect theory that tiny particles called gemmules from all parts of the body contribute to heredity.

HIV Origin

HIV originated from cross-species transmission of SIV from primates to humans, occurring multiple times.

Vestigial Traits

Remnants of organs or structures that had a function in an early ancestor, such as the human appendix.

Natural Selection

The process by which organisms with favorable traits are more likely to survive and reproduce.

Phylogenetic Tree

A diagram that represents evolutionary relationships among taxa, showing nodes (common ancestors), branches (lineages), root (ancestral lineage), and tips (species or groups).

Homoplasy

Similar traits in organisms that did not arise from a common ancestor, which can mislead phylogenetic inference.

Artificial Selection

The process by which humans select traits in organisms for reproduction, differing from natural selection.

Fitness

The relative reproductive success of an individual or genotype.

Adaptation

A trait shaped by natural selection that enhances an organism's fitness in its environment.

Synapomorphy

A shared derived trait used to define a group of organisms, such as hair in mammals or feathers in birds.