What are some examples of cladistics?

2 Answers
Sep 28, 2014

Cladistics is one of the primary methods of constructing phylogenies, or evolutionary histories. Cladistics uses shared, unique characters to group organisms into clades. These clades have at least one shared, unique character found in their most recent common ancestor that is not found elsewhere, therefore they are considered more closely related to each than to other groups.

These shared characters can be morphological, like bone structure or muscle composition; behavioral, like nocturnal/diurnal patterns; molecular, like DNA or protein composition; and more.

For example, the primates can be considered a clade as they have multiple shared, unique characters they inherited from a common ancestor, and these characters are not present in other groups (or if present, are of markedly different origin). In primates, this would include adaptations for living in trees, large brain size, slower rate of development, and more.

Check out this image for a visual representation of clades:
MedSocNet Illinois

Clades include all the descendants of a common ancestor so you can see that some of these groups are not strictly clades.

There are also other helpful terms in cladistics like mono-, para-, and polyphyletic groups. For more information on those, feel free to ask another question or check out the site below.
Monophyletic, Paraphyletic, Polyphyletic Groups explained

Feb 10, 2015

a method of classification of animals and plants that aims to identify and take account of only those shared characteristics which can be deduced to have originated in the common ancestor of a group of species during evolution, not those arising by convergence.