Taxonomy

Taxonomy: Defining groups of organisms based on similar characteristics. The result is a branching structure called the phylogenetic tree 4 pieces of evidence used to determine an organisms place in the phylogenetic tree.

1) Evolutionary Relationships Evolutionary relationships: The fossil record gives us a time table of which organisms were present on planet earth at which time Eg. Earliest known fossils were small impressions made by bacteria. This tells us that they were present before larger animals.

2) Biochemical Relationships Biochemical Relationship: Organisms use the same molecules to care out basic functions Eg. DNA is used as a genetic blue print for organisms Eg. 2: ATP (adenosine triphosphate) is used to produce energy by most organisms

3) Homologous Structures Analogous Structures: - Structures that have a similar function but do not have similar anatomy Eg Both the bird and insect wing is used for flight but structurally they are completely different Vestigial Structures: - Structures that arose from a common ancestor and are found fully developed in one species but reduced in another - The reduced structure is known as vestigial

3) Homologous Structures Homologous Structures: -Anatomically similar structures found in different species - These structures are similar because they evolved from a common ancestor

4) Embryonic Relationships Embryonic Relationship: All vertebrate embryos have homologous structures. These structures include a postanal tail and pharyngeal pouches

4) Embryonic Relationships Embryonic Relationship: All vertebrate embryos have homologous structures. These structures include a postanal tail and pharyngeal pouches

Using the 4 bits of evidence to determine a species’ place in the tree 1) Evolutionary relationships and the Fossil record: Species found in earlier fossils are found at the base of the tree. Younger fossils are found higher up in the tree.

Using the 4 bits of evidence to determine a species’ place in the tree 2) Biochemical Relationships: Species that have more biochemical similarities are more closely related and are therefore closer together in the tree

Using the 4 bits of evidence to determine a species’ place in the tree 3) Homologous Structures: Species that are closely related have a greater number of homologous structures.

Using the 4 bits of evidence to determine a species’ place in the tree 4) Embryonic relationships: There are more similarities in the structures of closely related species then distantly related one

Assignment Taxonomy: Making up and organizing animals