Fish Phylogenetic Tree Based on Protein Size
Fish phylogenetic tree based on protein size
Amanda Reed
Lab partners: Lecia Redwine, Kyle Hatcher
TA: Baneshwar Singh
Biology 117, Section 25
Tuesday 10:30 AM
Introduction Although tree diagrams have been used since the days of Charles Darwin, biologists have only recently adopted the tree model of evolution to read and interpret phylogenies. One of the reasons for this is the confusion that often arises from using a tree model to describe a phylogeny (Baum, 2008a). Many people interpret the trees to show that different species evolve from one another instead of viewing them as ways to trace the common ancestors between species. All species at the tips of the branches should be thought of as being evolutionarily equal; however, many people misinterpret the trees to show how different organisms evolved from one another (Baum, 2008b). Phylogenetic trees are a great way to represent how evolution led to the differentiation of species. However, to determine how to draw the tree, one must first define what a species is. Unfortunately, there is no black-and-white answer to determining the existence of new species. First, though, one must decide if a new organism is different enough from pre-existing species to constitute a new species or not. One must also have a method to detect new species. According to Ernst Mayr, organisms of the same species are able to reproduce fertile offspring. However, George G. Simpson argued that members of the same species have the same evolutionary history. Today, the two ideas have been combined to create the Biological Species Concept. This is still open for individual interpretation, so scientists, for the most part, have chosen to follow the Phylogenetic Species Concept which uses the most accurate phylogenetic trees available depicting organisms with shared traits to determine if an organism is a new species or not. Currently, the easiest way to depict the most accurate phylogenetic tree without using computer
Amanda Reed
Lab partners: Lecia Redwine, Kyle Hatcher
TA: Baneshwar Singh
Biology 117, Section 25
Tuesday 10:30 AM
Introduction Although tree diagrams have been used since the days of Charles Darwin, biologists have only recently adopted the tree model of evolution to read and interpret phylogenies. One of the reasons for this is the confusion that often arises from using a tree model to describe a phylogeny (Baum, 2008a). Many people interpret the trees to show that different species evolve from one another instead of viewing them as ways to trace the common ancestors between species. All species at the tips of the branches should be thought of as being evolutionarily equal; however, many people misinterpret the trees to show how different organisms evolved from one another (Baum, 2008b). Phylogenetic trees are a great way to represent how evolution led to the differentiation of species. However, to determine how to draw the tree, one must first define what a species is. Unfortunately, there is no black-and-white answer to determining the existence of new species. First, though, one must decide if a new organism is different enough from pre-existing species to constitute a new species or not. One must also have a method to detect new species. According to Ernst Mayr, organisms of the same species are able to reproduce fertile offspring. However, George G. Simpson argued that members of the same species have the same evolutionary history. Today, the two ideas have been combined to create the Biological Species Concept. This is still open for individual interpretation, so scientists, for the most part, have chosen to follow the Phylogenetic Species Concept which uses the most accurate phylogenetic trees available depicting organisms with shared traits to determine if an organism is a new species or not. Currently, the easiest way to depict the most accurate phylogenetic tree without using computer
Cited: Baum, D. (2008a) Reading a phylogenetic tree: The meaning of monophyletic groups. Nature Education 1(1) Baum, D. (2008b) Trait evolution on a phylogenetic tree: Relatedness, similarity, and the myth of evolutionary advancement. Nature Education 1(1) Hey, J. (2009) Why should we care about species? Nature Education 2(5) Ho, S. (2008) The molecular clock and estimating species divergence. Nature Education 1(1)