Key points: A phylogenetic tree is a diagram that represents evolutionary relationships among organisms. Phylogenetic trees are hypotheses, not definitive facts. The pattern of branching in …

To find the most recent common ancestor of any pair or group of species, start at the branch ends carrying the two species of interest and “walk backwards” in the tree until you find the point …

On a phylogenetic tree, the position of species like the eagle (a bird) and the alligator reflects their evolutionary history, specifically their shared common ancestors and the time at which their …

Review your understanding of common ancestry and evolutionary trees in this free article aligned to NGSS standards.

Interpret fossil, anatomical, and genetic evidence to understand how species are related through common ancestry. Use phylogenetic trees to represent evolutionary relationships and justify …

And what we're going to try to do in this video is construct a tree for showing how different species evolved from common ancestors, and we're gonna do it based on some of these observable …

And what we're going to try to do in this video is construct a tree for showing how different species evolved from common ancestors, and we're gonna do it based on some of these observable …

In this view, living organisms form a huge, branching tree with many levels, in which all present-day species can trace their lineage back to a common ancestor. Today, most biologists define …

Learn about phylogenetic trees and how to interpret them to determine which species are most related.

In this unit, we'll examine the fossil record and learn how to interpret phylogenies and evolutionary trees. Taken together, these tools can help us to understand the story of life's evolution on our …