corREXion?

This article was originally posted at Science 2.0 on 21 April 2010 as a follow up to my article What Do Ardi, Raptorex, and Komodo Dragons Have in Common?. In light of recent debate* about Raptorex’s identity I thought this was worth a second look.

 

Raptorex by Nobu Tomura (GNU Free Documentation License)

 

Normally, being wrong sucks. It’s all -10 points and you don’t get into Harvard. Sadness. But, not in science. One of the best things about scientific method is that it makes being wrong fun. That does not mean that scientists always like to hear they are wrong. We are after all sinful, prideful beasts like the rest of you – just smarter – just kidding.

A while ago, I discussed some relatively recent, amazing contributions of paleontology in order to illustrate that, while DNA may trump fossils for reconstructing evolutionary histories and the relationships between organisms, paleontology provides information on physiology and geographical location that can only be inferred by other disciplines. One of the discoveries discussed was of a 125 million year old, man-sized Tyrannosaurus rex ancestor, Raptorex, reported in Science on 17 September 2009. Continue reading “corREXion?”

What Do Ardi, Raptorex, and Komodo Dragons Have in Common?

This article was originally posted at Science 2.0 on 9 October 2009. It provides some background for the follow-up article corREXion? that has suddenly become relevant again.

Paleontology doesn’t always get the respect it deserves (or desires), in the molecular, genomic, evolutionary, quantitative genetic circles we run in around here. Blame the DNA. Sequence comparisons have proven incomparable in establishing phylogenetic relationships between organisms.

Paleontology can also irritate us by creating false controversy, which irritates the heck out of us. The fossil record is a sparse and biased record of life. Supposed “missing links” are often an artifact of this fact. Supposed discrepancies between sequence divergence times and divergence in form from the fossil record often reflect the fact that sequence divergence necessarily precedes any differences in form significant enough to be noticeable in the fossil record.

This means that biologists tend to relegate paleontology (fairly or not) into the roles of adding colorful detail. Therefore, it is particularly exciting when there are not one, not two, but three recently reported fossils that force the biological community to re-evaluate evolutionary hypotheses. Continue reading “What Do Ardi, Raptorex, and Komodo Dragons Have in Common?”