Intro to Phylogeny

Phylogeny Phylogeny is the study of evolutionary lineages of a species, or group of species.Watch "Tree Diagrams" video and add the missing information in the blanks below to summarize what you have learned. To show how living things are related, scientists organize them into branching tree diagrams.The base represents a hypothetical common ancestor, and the organisms at the tip represent living descendants. The branches represent lineages of ancestors.The branch points or nodes represent common ancestors, or more specifically the most recent ancestor that is common to all the branches beyond it. Connections to common ancestors can tell you which creatures are more closely related. Another way to look at relatedness is to look at the number of traits that the creatures have in common.One thing that’s really important to know about trees is that the order of organisms across the top doesn’t tell you anything, the key information is in the branch points. Interpreting Phylogenetic Relationships Use the information from the "Tree Diagrams" video and the cladogram below to summarize the relationships between five species, A, B, C, D, and E. What trait separates species A from B? Added body segment Longer abdomen Wings Antennae Which of the following species have longer abdomen as one of their traits? Select ALL that apply A B C D E To find the most recent common ancestor of any pair of species, start at the branch tips carrying the two species of interest and “walk backwards” in the tree until you find the branch point (node) where the species’ lines meet.What two species share an ancestor closest to the present time? A B C D E To find the most recent common ancestor of any pair of species, start at the branch tips carrying the two species of interest and “walk backwards” in the tree until you find the branch point (node) where the species’ lines meet.Which number represents the most recent common ancestor of species A and B? 1 2 3 4 To find the most recent common ancestor of any pair of species, start at the branch tips carrying the two species of interest and “walk backwards” in the tree until you find the branch point (node) where the species’ lines meet.Which number represents the most recent common ancestor of species C and D? 1 2 3 4 In a phylogenetic tree, two species are more closely related if they have a more recent common ancestor, and less closely related if they have a less recent common ancestor.Which species are more closely related, A and B or C and D? A and B are more closely related because they share a more recent common ancestor C and D are more closely related because they share a more recent common ancestor