First up, a fossil claw of the eurypterid (sea scorpion) Jaekelopterus rhenaniae could have come from the largest arthropod that ever lived. The claw, described in Biology Letters, measures 46 cm in length, and presumably was part of a Jaekelopterus individual 2.5 meters (8.2 feet) long. The story has been well-covered by National Geographic News, The Loom, and Palaeoblog.

This week’s issue of the journal Science has a few brief articles on research presented at last month’s Society of Vertebrate Paleontology Annual Meeting. One provocatively titled story, “Did Horny Young Dinosaurs Cause Illusion of Separate Species?”, reports on the work of John Horner, Mark Goodwin, and Holly Woodward, which suggests that the spiky-headed pachycephalosaurs Dracorex hogwartsia and Stygimoloch spinifer might, in fact, be juvenile forms of the knobby domehead Pachycephalosaurus wyomingensis. Update (11/24): Manabu Sakamoto has a summary of Horner et al.’s presentation up at his blog, Raptor’s Nest.

Finally, researchers at the Royal Tyrrell Museum have announced the discovery of a new ceratopsian dinosaur: Eotriceratops xerinsularis (ee-oh-try-SAIR-ah-tops zeer-in-soo-LAIR-iss), the “Dawn Three-horned face from Dry Island (Buffalo Jump Provincial Park)”. This 68,000,000 year old dinosaur is a couple of million years older than Triceratops, and it may be the ancestor of that well-known genus. Eotriceratops and Triceratops shared several features such as large brow horns and a solid frill, but Eotriceratops also possessed some more primitive characteristics than its younger relative, according to this story in the Edmonton Journal. The three-meter-long skull of Eotriceratops (reconstructed in this photo) would seem to put it in the running for the largest head of any terrestrial animal, alongside other ceratopsian contenders such as Torosaurus and Pentaceratops.

Image by Ray Troll

Scientists have determined that the giant Devonian placoderm Dunkleosteus had one of the most powerful bites of any animal ever. This monstrous armored fish reached the size of a school bus and ate darn well anything it pleased. It’s gaping maw apparently opened at an amazing speed and was able to chomp down with astounding force. How one is able to draw conclusions like this from a pile of ancient bony plates is a bit beyond me…but hey it’s been written up in the Royal Society’s journal called Biology Letters. One thing is for sure though: Dunkleosteus was one of the wickedest looking fishes to ever swim the seas!

Further Reading:
Anderson, P. S. L., and Westneat, M. W. 2006 Feeding mechanics and bite force modelling of the skull of Dunkleosteus terrelli, an ancient apex predator. Biology Letters FirstCite early online publishing doi:10.1098/rsbl.2006.0569

The official press release.

The story at Science Daily.
An in-depth article from the Chicago Tribune.

Yahoo News has the story also.

This and all other art by Ray Troll

If you trace our family tree 370,000,000 years back to the Late Devonian, this could well be the face of our long-lost mother. Meet Tiktaalik roseae, the newly described lobefinned fish from Nunavut, Canada. The name Tiktaalik comes from an Inuit word for the fish we call burbot, after local elders noted the similarity between the fossil and the large living fish they catch.

Unlike its namesake, however, Tiktaalik is a member of the great fish clan Sarcopterygia. Sarcopterygians acheived enduring fame, glory, and eventually cheeseburgers after certain members evolved the means to crawl out of the water and taking the first steps (literally) to a totally landlubbing lifestyle. Tiktaalik fits into this story quite well, sporting a set of characters more amphibian-like than all other fish, but more fish-like than the earliest amphibians.

Our very own curator of Ich-theology (the study of Fish Worship), Ray Troll, appreciates more than most the duality of being a totally terrestrial tetrapod while embracing our fishy lobe-finned heritage.

Ray created this suite of Tiktaalik art after learning about this amazing find. Not only that, it inspired him to write and record The Devonian Blues, a lament for wayward sarcopterygians (download the mp3). You can read his thoughts about Tiktaalik, peruse his art, and watch The Devonian Blues music video at his website.

Pharyngula has all the technical imagery, and Palaeoblog has some additional restorations.

A Devonian tetrapod-like fish and the evolution of the tetrapod body plan. 2006. Edward B. Daeschler, et al. Nature 440: 757-763

You know that snarky feeling you get when you blow your nose too damn hard and you blow your eardrums out? Well it just might be that we have our fishy ancestors to thank for that lovely sensation. We all know that the knee bone’s connected to the thigh bone but only vaguely suspect that our lungs are connected to our ears. But once upon a time, way, way back in the Devonian days, our fishy ancestors may have been able to breathe through their ears! How cool is that? Just imagine the possibilities if we could still perform such a feat: you could fake your own drowning death in the family bathtub, win all those driving-by-the-graveyard-and-holding-your-breath contests, and snorkels would be obsolete.

“One Small Step for a Fish”
Panderichthys (bottom) and Acanthostega (top)
© Ray Troll

But seriously, Drs. Martin Brazeau and Per Ahlberg closely reexamined the inner ear chambers of the Devonian lobefin fish Panderichthys and came to the conclusion that the fish used it’s ear to gulp air. Their findings are published in the January 18, 2006 issue of Nature . Read all about it at Nature online.

I’ve long been curious about the positioning of the nostrils on the lower part of the head in this group of fish and this theory helps answer that puzzle.

We’ve also included the lyrics to the song. You inherited your lungs from our Devonian ancestors, so do them proud and sing it loud!

Here’s wishing everyone a Happy and Hairy New Year!

We’ve come once again to the time of year when folks get together and celebrate the birth of a certain Middle-Eastern Fish Man. In keeping with the piscine spirit of the holiday, the Hairy Museum is proud to present work by our resident Curator of Ich-theology, Ray Troll.

Ray’s work takes us back to the Devonian Period (appropriately, “The Age of Fishes”), when a group of lobe-finned fish were taking some of the most radical steps in vertebrate evolution—the shift from an aquatic lifestyle to a terrestrial one. Ray has long been inspired by those who made this great transition, and has created a series of portraits of these notable ancestors, and reflections on what it means to be part of the great lobe-fin family.

After the hustle and bustle of the holiday dies down we’ll get more images up in a dedicated gallery in our expanding Hall of Ich-theology. Until then, however, embrace your inner fish by downloading and playing the following tune, written and performed by Ray in honor of our grand sarcopterygian heritage:

The Devonian Blues
(3.2 MB mp3)

“Your Momma was a lobefinned fish.
My Momma was a lobefinned fish…”

More of Ray’s art, music, and celebration of the fossil record can be found at his outstanding Fin Art website.

Long portrayed as a sort of fish-faced salamander, the new study shows that Ichthyostega had developed some very interesting landlubbing adaptations that were previously unrecognized.

Fish and most other early tetrapods have a spinal column where one vertebra looks quite similar to its neighbors, forming one long bony ribbon that is particularly flexible in side-to-side movements. But the spine of Ichthyostega was quite specialized. It had distinct neck, chest, lumbar (lower back), hip, and tail vertebrae that were largely useless for side-to-side wiggling, but were well adapted for more of a bounding motion, allowing it to galumph across the Devonian shoreline something like a hurried seal.

Pharyngula has more information on the article, including a comparison of old and new skeletal reconstructions. Afarensis has a great writeup on the functional and evolutionary implications of the study, along with several photos of Ichthyostega fossils.

Figures from the Nature article are available here.