Skip to main content

Animal Phylogeny as Evidence-Based and Revisable

This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.

State

The animal phylogenetic tree, per Bio 1787 and Bio 0076, is built from morphological, developmental, and molecular evidence together, and shifts as new evidence arrives.

Show

Molecular sequence data has repositioned several animal lineages relative to earlier trees built from body-plan comparisons alone.

Watch for

A textbook animal tree states the current best-supported hypothesis, not a discovered, unchanging fact about ancestry.