If you like trilobites (and we all do)…

This is so off-topic, but Mitt Romney is a real gift to the rational. Check out this comment in response to a post about Romney's canine mistreatment:

Angel moroni

I was considering voting for Romney until I read this, even though I have serious doubts about the credulity of someone who believes a hillside in Palmyra, NY opened up and the angel Moroni stepped out with the gospel on gold plates.

The rejoinder is too obvious to even write down.....

Ick, just look like giant roaches to me.

I can't explain why, but Trilobites really are immensely cool. I wish they came as pets, in the size of a small dog... One can only fantasize *sigh*.

Time to make trilobite cookies again!

Thirty years ago, doing programming stuff on an IBM mainframe, we were charged for (among other things) memory usage in kilobyte-hours. It always made me think of a store that rented trilobites by the hour...

For those who want more of those pictures (and the science behind them), check out Sam Gon III's site: http://www.trilobites.info.

I never realized how much a trilobite looks like an IUD.

anomalocaris!

Woh!

Beauteous! Thanks for sharing...

Did you open up the thumb-nail of the large trilobites?

They would have made really cool pets. I wonder what they tasted like. I could see sitting down with a big bowl of hot butter and a lobster bib.

Trilobites are SO cool. (I betcha Dan O'Bannon thinks so, too.) Do we know what creatures are the trilobite's closest living relatives? I seem to remember reading that the superficially obvious choice, the horseshoe crab, is not one of them. As always, I could be mistaken...

Do we know what creatures are the trilobite's closest living relatives? I seem to remember reading that the superficially obvious choice, the horseshoe crab, is not one of them. As always, I could be mistaken...

I think you're right. Horseshoe crabs are, I think, more closely related to spiders and ticks.

But I'm not quite sure where trilobites fit in there, so they could be close, too.

I don't think trilobites left behind any descendants. Just really cool fossils. Their closest relatives are just arthropods in general.

Wow. I'd always thought "the trilobite" was a single species. I never realised there were so many different species of them, including ones with spikes, barbs, and even freaky tentacles growing out their heads. Thanks for that, PZ.

wow! thanks for ultra cool link...for other trilobite fans, there's a fab book on trilobite anatomy called Trilobites (not surprising) that discusses some of the different species and species-specific traits. it's by Levi-Setti - finally found the book in Moe's at berkeley - it totally rocks.

Though trilobites are readily recognized to be arthropods, their closest relatives among the arthropods is much less clear. The usual hypothesis is that they are closest to the chelicerates, a group that includes the arachnids and the horseshoe crabs (Xiphosura).

However, horseshoe crabs may be relatively primitive; they have had relatively little macroscopic-feature change since the Silurian, over 400 million years ago. That does not mean that there was none, of course; the earlier horseshoe crabs had separate rearward segments, while those segments are fused in present-day ones.

And trilobites reminds me of pillbugs, which are isopod crustaceans. They can even roll themselves up in pillbug fashion.

Yes... Now that you mention it, it seems to me that isopods in general are morphologically more evokative of trilobites than are their (probable) closer descendants (arachnids). Either way, their coolness index is pretty high. :-)

Errr... Evocative, even.

Either way, their coolness index is pretty high

Very nice