Section 5 Branching Trees How does a branching

Section 5: Branching Trees How does a branching tree diagram show evolutionary relationships?

Inferring Species Relationships Key concept: Scientists have combined the evidence from DNA, protein structure, fossils, early development, and body structure to determine the evolutionary relationship among species. Compare genes to determine how closely related species are More similar DNA is more closely related organisms are In most cases evidence from DNA and protein structure confirm hypotheses on fossils, embryos and body structures

Kaibab and Abert’s Squirrels v Two kinds of squirrels isolated from one another by the Grand Canyon for a long time v This isolation may result in two different species v They belong to the same species but have different characteristics *an example of Geographic Isolation Kaibab Abert’s

A Branching Tree This branching tree shows how scientists now think that raccoons, lesser pandas, giant pandas, and bears are related.

A Branching Trees Diagram- show probable evolutionary relationships between groups of organisms. It also shows the order in which specific characteristics may have evolved.

Constructing a Branching Tree Organism with none of the characteristics are at the bottom Next fork put group with one shared derived characteristics Branch above that put organism with two shared derived characteristics Continue until you end with the organism that has the most shared derived characteristics

Reading a Branching Tree Diagram 1. Did crocodiles evolve from amphibians? No they are on different branches of the branching tree. 2. Are rodents more closely related to primates or crocodiles? Primates they are on a branch together with other. 3. Name a common ancestor between crocodiles and dinosaurs. Two post-orbital fenestrae

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