Nigersaurus, a Cretaceous hedge-trimmer

Blogging on Peer-Reviewed Research

Last August, when I was at the Sci Foo camp, Paul Sereno brought along the skull of one of his latest discoveries…and whoa, is it ever a weird one. This is Nigersaurus taqueti, an herbivorous dinosaur with specializations for ground-level grazing. Look at this picture; in reality, it’s even more striking.

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Those jaws and teeth—they are so neatly squared off and flat-edged. In addition, the skull itself on the spinal column is turned habitually downward. This is a creature that kept its face pressed to the ground as it nibbled its way across the landscape.

Another feature that was apparent is that the skull is awesomely light — it’s mostly empty spaces with a delicate webwork of bony struts holding it together. It’s so specialized it’s almost comical, and you can imagine something like this appearing on the Flintstones as a lawn mower or hedge trimmer.

Bora has more, and you can read the original on PLoS.

Sereno PC, Wilson JA, Witmer LM, Whitlock JA, Maga A, et al. (2007) Structural Extremes in a Cretaceous Dinosaur. PLoS ONE 2(11): e1230. doi:10.1371/journal.pone.0001230

Yicaris dianensis

Blogging on Peer-Reviewed Research

Early Cambrian shrimp! I just had to share this pretty little fellow, a newly described eucrustacean from the lower Cambrian, about 525 million years ago. It’s small — the larva here is about 1.8mm long, and the adults are thought to have been 3mm long — but it was probably numerous, and I like to imagine clouds of these small arthropods swarming in ancient seas.

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The head limbs are drawn in median view and the trunk limbs in lateral view.

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Lucy’s legacy

As I’ve mentioned before, Lucy is going to be in Houston at the end of this week for an extended stay. This is not entirely a joyous occasion in the scientific community: many people, including Richard Leakey, are not happy that such a precious specimen has been subjected to the risks of travel. I sympathize. The bones of Lucy must be treated with the utmost care and regard, and any loss or damage would be an awful tragedy. However, there’s more to it than preserving an important fossil: Lucy is a touchstone to our past and is a symbol of the importance of our long history. We need to bring the ancient world to life for our citizens, and for not entirely rational reasons, people will want to see the real thing. I see that someone else shares my sentiment:

There is a wanton arrogance alive and kicking within the general scientific community. An arrogance that clings stubbornly to fact while at the same time stridently denying reality. And it pisses me the hell off. The facts in this case are clear: Lucy is one of the oldest hominid fossils ever discovered, and is very valuable for researchers. The reality of the situation is equally clear-cut, if a bit harder for the critics to swallow: Nobody gives a shit about replicas. Does it look the same? Sure. Can 99.9 percent of the population not tell the difference? You betcha. Does that matter? Not one iota. You see, for all the cranial capacity human beings have developed since little Lucy made do with a glob of gray matter the size of a key lime, we are not rational thinkers. Homo sapiens are, first and foremost, irrational and emotional.

I wouldn’t go so far as to call it arrogance, but there is a little selfishness to it, and most importantly, there’s a deep appreciation of the importance of that long-dead individual and a greater fear of its loss. What balances that fear, though, should be the recognition that other people could also stand to learn to love that tiny scrap of our long-past ancestry — the Lucy exhibit is an opportunity to teach.

Shouldn’t that be part of our mission? In addition to our own intimate learning of science, the task of sharing it with everyone else?

Clearly, bloggers need to take over science journalism

Aaargh. When will the media learn? National Geographic is running this ridiculous headline right now: New Fossil Ape May Shatter Human Evolution Theory, in which the reporter claims a discovery of some teeth could “demolish a working theory of human evolution.” It’s not true. Where is this nonsense coming from?

I read the article. It’s titled “A new species of great ape from the late Miocene epoch in Ethiopia.” The exciting news is that the “combined evidence suggests that Chororapithecus may be a basal member of the gorilla clade, and that the latter exhibited some amount of adaptive and phyletic diversity at around 10-11 Myr ago.” It concludes with a suggestion that we need to do more research in sediments appropriate to Miocene apes. There aren’t an exploding paradigms or revolutions suggested.

I read the associated news article in Nature. It’s titled “Oldest gorilla ages our joint ancestor.” It says that this discovery pushes back the time of divergence of the gorilla lineage from our own. This is just ordinary science.

Now read the blogs — they’re doing a much better job of evaluating this work than the traditional media. For one thing, they’re actually looking at it critically. Afarensis points out that these are only a few teeth, and it’s awfully thin grounds for a substantial revision of the timeline. John Hawks makes a similar point, but also highlights the fact that there is an unresolved problem — we need to reconcile paleontological and molecular dates. Even John Wilkins, a “mere” philosopher, weighs in sensibly that teeth are plastic characters in phylogeny, and deplores this peculiar media habit of taking a recalibration of a historical detail as a major reformulation of theory. All these discussions are sober and interested and most important of all, accurate.

The lesson is clear: when you see some wild and crazy claim of scientific revolutions and the demolition of long-held theories, go immediately to the science blogs for some clear-eyed sanity and informed evaluation from experts.

Lucky Houston gets Lucy

The state department has approved a visit from an eminent foreigner: a certain 3.2 million year old australopithicene is going to be at the Houston Museum of Natural Science from 31 August 2007 through 20 April 2008…and then she’s going on tour. Future locations haven’t been determined yet, but Minneapolis is nice. Chicago would be OK. I hope I get a chance to pay court on her.

Just a thought, but the creationists have got it all wrong. They think we worship Charles Darwin, but actually, if there are any objects of reverence among evolutionary biologists, it would be the evidence — the bones of Lucy, of Archaeopteryx, of Tiktaalik, the little trilobite in shale that I keep by my hand at my office desk.