[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
labels are imaginary
Time to vent my spleen. Cladistic analysis is a useful tool in
understanding phylogeny, but the whole cladistic system of naming things
is in my opinion a little absurd.
Taxonomy and systemtics, cladistic or otherwise, is an attempt to
uncover the phylogenetic relationships of living and extinct organisms.
There is a concrete phylogenetic tree at the heart of the search. If you
say "these things evolved from these things", it is either true or false.
It did happen that way or it didn't. No one is 100% sure what that
concrete phylogeny was, and everyone has thier own ideas, but the point
is that phylogeny is not subjective. Organisms are related in a certain,
Not so when you start assigning labels. The names we give things,
whether its "clade" or "family" or "outgroup" or whatever, are imaginary.
They don't exist. The only reason we come up with
them is to help our own undertstanding of the way the phylognetic tree
is put together. You can say "birds are descended from dinosaurs" or
"avain dinosaurs are descended from non-avain dinosaurs", but it
doesn't really matter because you are saying the same thing,"These things
descended from these things". You could take any cladogram and modify it
into a "kingdom-phylum-class..." phylogeny without altering the
relationships of the organisms one whit. You just draw the
imaginary dotted lines in different places. Whether you say
"we are crossopterygians because we are descended from them"
or "we are descended from crossopterygians but are different
enough to call ourselves something different", matters not a whit because
you have not altered the relationships of the organisms.
The point I'm making is just that we assign labels only for
our understanding. So why say "avian dinosaur" and "non-avian
dinosaur" when you could just say "bird" and "dinosaur"?
Cladistics has created a convoluted naming system that
does not clarify things any better than the traditional
system. Whats the point?