Week 2 Lab Study Guide

Macroevolution

Major evolutionary change. The term applies mainly to the evolution of whole taxonomic groups over long periods of time.

Vestige

A part or organ of an organism that has become reduced or functionless in the course of evolution.

Homology

The state of having the same or similar relation, relative position, or structure.

Cladogram

Diagrams which depict the relationships between different groups of taxa called “clades”.

Taxon

A taxonomic group of any rank, such as a species, family, or class.

Node

The points where the lines intersect are the common ancestors in a cladogram.

Synapomorphy

A characteristic present in an __ancestral__ species and shared exclusively (in more or less modified form) by its evolutionary descendants.

Clade

A group of organisms believed to have evolved from a common ancestor, according to the principles of cladistics.