BIOL 123 Lecture Notes - Lecture 4: Ribose, Theropoda, Ecological Niche
Document Summary
Testing hypotheses with phylogenies: from sea to land. Many traits are integrated in a way that allows the organisms to thrive in a specific ecological niche. To find more clues about the transition from water to land, we need to add the branches belonging to extinct taxa. Sometimes homology between traits of different species is obvious: human and orangutan foot (similar with different size and shape) Sometimes it can be difficult when distantly related: need to trace evolution of that specific trait. Three living branches of mammals: monotremes, therians: marsupials and eutherian. Phylogeny of mammals and relatives demonstrates how they mammalian body plan gradually emerged. Traits often change their function over the course of evolution. Phylogenies help track this transformation by linking homologous traits in different taxa. Exaptation: borrowed traits - is a trait that initially carries out one function and is later co-opted for a new function the original function may or may not be retained.
