Evolutionary Relationships

Humans have classified and organized biological organisms for thousands of years. Originally, primarily ordering objects necessary for survival. As human history progressed, so did the skill and detail in these classifications. In the fourth century B.C., Aristotle pioneered formal classifications, delineating plants and animals into different groups and then dividing these further based on their physical characteristics and traits like the habitats that they occupy. Later, in the mid 1700s, Linnaeus built on Aristotle's system. He called his highest level of grouping the kingdoms and, from there, divided the groups using synapomorphies, a defining physical feature which splits a branch. For example, if an animal possesses a backbone or a similar structure, it should be placed in the phylum chordata. If it doesn't, then there are many other phyla, which animals without backbones can be split into, including the arthropoda, a large group including insects. Linneaus continued splitting groups of organisms based on their synapomorphies at subsequent levels through the class, order, family, and genus, until reaching the final designation, generally, the species. We refer to Linnaeus' t