Phylogeny

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Phylogeny is a biological term describing the relationships between groups of animals according to their evolutionary heritage, as best understood by information from genetics, paleontology, embryology and anatomy.

The pattern of evolutionary relationships within and between groups can be depicted in the form of a branching diagram called cladograms, which are like genealogies of species.

A simple cladogram relating five groups of animals by the similarities and differences.

Not only is phylogeny important for understanding paleontology, but paleontology in turn contributes to phylogeny. Many groups of organisms are now extinct, and without their fossils we would not have as clear a picture of how modern life is interrelated. Genetics has been the single most important part of modern plylogeny, reorganizing where some animals go based on genes and ignoring superficial characteristics that suggest closer relationships. For example, the common bat is actually two distinct phylogenic groups traditionally classified just as "bats", but genetics suggests these bats evolved side by side rather than sharing a common 'bat' ancestor.[1]

Phylogenetics[edit]

Main article: Phylogenetics

Phylogenetics, the genetic science of phylogeny, is one part of the larger field of systematics, which also includes taxonomy. Taxonomy is the science of naming and classifying the diversity of organisms. While they share similar results, the methods used to create their classification systems are quite different.

Phylogenetics, starts with the mapped gene, and compares how closely it resembles other animal's genes. The more mapping that is done, the more precise the phylogenetic tree becomes.

Taxonomy on the other hand, generally begins with the living (or fossilized) animal and compares biological structures, habits, diet, etc., to create relationships.

Because evolution is a fact, both trees look remarkably similar.

See also[edit]

References[edit]

  1. Karyotypic evolution in bats: evidence of extensive and conservative chromosomal evolution in closely related taxa