Possible evidence of surviving 'fossil' species

Previously posted on ID in thread 239.

The article Secret Survivor describes the search of a group of scientists to find on the sea-floor a species usually thought to be extinct, Paleodictyon:

�Extinct� for 50 million years, an enigmatic fossil species may still live at the bottom of the sea�but it defies capture.

There are currently two theories about Paleodictyon. One is that it's a worm-like creature, about 0,2 cm wide and 2 cm long. The other is that it's a sponge-like creature that lives in the entire network of tunnels:

Two hypotheses for its origin are being tested. One is Seilacher's original explanation, that the form is constructed as a burrow by an as-yet-unknown worm. The alternative hypothesis is that the form itself reflects the shape of the organism, perhaps a large single-celled organism whose living tissue fills the horizontal network. In that event, the organism might take up the sediment to make a kind of hexagonal exoskeleton, leaving holes in the sediment open to catch food from above. These studies are in progress. After nearly thirty years, to my surprise, the mystery of Paleodictyon still seems as deep as the waters where it lives.

This thread doesn't seem to be getting the attention it deserves so i'll reply. I read the link you provided amantine, great find. I have a couple questions regarding this, how many creatures have they estimated are living off chemosynthesis? It's an interesting section of science. My other question is can we safely say that there are many more fossil species alive at the bottom of the sea - perhaps larger ones?

Wow what other kinds of ancient animals there gonna find living in remote parts of the world.

They don't look to be quite the same tho do they?

The trace fossil:

Photo of ocean floor from P. A. Rona, 1978, �A benthic invertebrate from the Mid-Atlantic Ridge,� Bulletin of Marine Science, 28(2):371�375.

and now the observed print on the ocean floor near the smokers:

Photo courtesy The Stephen Low Company

Now, they are saying that the photo would be holes left above where the trace fossil (the hexagons) would be. I think that that would make this a rather unusual organism, sort of like a coral that instead of building corals around it sits in the mud. I wonder if it does make more sense then that these hexagonal shapes are preserved, whereas the top holes apparently aren't, because the holes are just mud and the hexagons are an actual organism that can sit there and get fossilized. Of course, burrows can get fossilized on their own too.

It really is amazing what they've been finding at the deep ocean vents. THe implications for abiogenesis experiments themselves have been astounding, let alone the bizzare menagerie of creatures down there.