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Re: Koreanosaurus, new burrowing ornithopod [Meta]



I think that, at a point, it is not so weird to give a phylogenetic
judgement without a computerized phylogenetic analysis. For example,
if we get some frog in the field, we can be reasonably certain, from a
series of features observed, that it is closer to a toad than to us
and a dog, without the need to enter it into a matrix (and I say
reasonably certain because, with a phylogenetic analysis, the
relationships of the taxon may not be those supposed with the help of
the computer... but the same applies to the phylogenetic placement
derived from a cladogram, for future phylogenetic analyses using more
data -characters and taxa- the phylogenetic position favored by the
hypothesis proposed by an analysis may not hold). Even more, something
similar to this occurs when scientists find some vertebrate with many
titanosaur features. They do not include it into a data matrix
containing all dinosaurs, they generally include it in a matrix
containing only sauropods. They do not test it being a dinosaur,
amniote, or vertebrate, they just test to which sauropod subgroup it
corresponds. They aprioristically accept the supposition it is a
sauropod. Of course, it is entirely understandable, because of the
great work it would take to include, say, all vertebrates, amniotes,
or dinosaurs. These tests are likely never complete, and lacking a
matrix is just an extreme of that continuum of uncertainty (because it
derives hypotheses from few data - the more complete the test the more
data you employ). Although, one may consider, supporting Tim's
position, that using a phylogenetic analysis permit to better
ascertain that we are choosing the most parsimonious hypothesis,
whatever the low amount of evidence you employ in your systematic
judgements.