#57193: Alon Levy — 01/10  at  09:55 AM
It's the first time I hear of pre-Cambrian chordates - I always thought the earliest known chordate fossil was pikaia. Can you explain what is presently known about how chordates evolved?

While we're at it, your site is loading awfully slowly. Are you getting links from Kos again?

#57203: PZ Myers — 01/10  at  10:42 AM
No, it's just everyone and everywhere. I am seeing mockups of the new site (professionally designed and powerfully hosted!), though, so I'm hoping to fix this all up soon.

#57210: Alon Levy — 01/10  at  11:00 AM
Good - if I can't read Pharyngula, I'll have to actually get some work done...

#57212: — 01/10  at  11:01 AM
Wow. So if both the protostome and deuterostome clades were already represented in the Pre-Cambrian, doesn't the Cambrian "explosion" become even less impressive?

#57219: — 01/10  at  11:28 AM
Wow...that's breathtaking...anyone knows why these guys sit on their fossils instead of publishing data about them? They would for sure make a Nature cover story!

#57300: — 01/10  at  06:02 PM
Is this the only example of Precambrian chordates? If so is it enough to show that the Cambrian Explosion was just an explosion of fossilization not of body types? (Not that that will make any difference to creationists).

#57601: arensb — 01/12  at  07:07 AM
Here's something that's been bugging me for a while: judging by the photos, this fossil (and many others) is just an impression in clay. With a dinosaur, you could get petrified bones and claws, but here the fossil consists of the shape between two layers of rock.

So how does one go about finding such a fossil? Is it simply a matter of the original rock splitting along geological layers, and someone being sharp-eyed enough to notice the fossil? Is it just dumb luck?