Wiktionary
n. (context systematics English): A biologist who studies clades, an evolutionary biologist who studies the pattern of species interrelationships according to the principles of cladistics.
Usage examples of "cladist".
These are the cladists, who follow the principles laid down in Willi Hennig's famous book Phylogenetic Systematics.
The main thing to remember at this stage is that, at least in principle, the cladist thinks about all possible bifurcating trees that might unite the set of animals he is dealing with, and tries to choose the one correct tree.
And the true cladist makes no bones about the fact that he thinks of the branching trees or 'cladograms' as family trees, trees of closeness of evolutionary cousinship.
The reason they do so is one of history: they started out as true cladists, and kept some of the methods of cladists while abandoning their fundamental philosophy and rationale.
I suppose I have no choice but to call them transformed cladists, although I do so with reluctance.
In their underlying philosophy, so-called transformed cladists have more in common with the other school of pure-pattern measurers, the ones often called 'pheneticists' or 'numerical taxonomists', whom I have just discussed under the title of average-distance measurers.
Like average-distance measurers, transformed cladists are not out to discover family trees.
But unlike the distance measurers, who, at least in theory, are prepared to let Nature tell them whether she is actually hierarchically organized, the transformed cladists assume that she is.
The transformed cladists, however, like the true cladists that they once were, bring in clustery, branchy thinking right at the outset.
Like true cladists, they would begin, at least in principle, by writing down all possible bifurcating trees, and then choosing the best.
It may not be easy to be sure which one is the correct one, but the true cladist can at least be sure that not more than one is correct.
The transformed cladist refuses to allow the concept of ancestry to enter his considerations.
It certainly is not possible, in the nonevolutionary world of the transformed cladist, to make strong and clear statements such as 'only one out of the 945 possible trees uniting 6 animals can be right.
No cladist actually draws flesh and blood ancestors on family trees, though traditional evolutionary taxonomists sometimes do.
Not content with a perfectly sensible belief that there is something to be said for leaving evolutionary and ancestral assumptions out of the practice of taxonomy, a belief that they share with pheneticist 'distance measurers', some transformed cladists have gone right over the top and concluded that there must be something wrong with evolution itself!