For decades, paleontologists have puzzled over a fossil collection of nine Triassic icthyosaurs (Shonisaurus popularis) discovered in Nevada's Berlin-Ichthyosaur State Park. Researchers initially thought that this strange grouping of 45-foot-long marine reptiles had either died en masse from a poisonous plankton bloom or had become stranded in shallow water.
But recent geological analysis of the fossil site indicates that the park was deep underwater when these shonisaurs swam the prehistoric seas. So why were their bones laid in such a bizarre pattern? A new theory suggests that a 100-foot-long cephalopod arranged these bones as a self-portrait after drowning the reptiles. And no, we're not talking about Cthulhu.
After considering the more brutal aspects of modern octopus predation, paleontologist Mark McMenamin of Mount Holyoke College came to the conclusion that the shonisaur remains had been deposited in a "kraken" lair by its massive, tentacled squatter. From his abstract of research being presented today at The Geological Society of America's annual meeting:
We hypothesize that the shonisaurs were killed and carried to the site by an enormous Triassic cephalopod, a "kraken," with estimated length of approximately 30 m, twice that of the modern Colossal Squid Mesonychoteuthis. In this scenario, shonisaurs were ambushed by a Triassic kraken, drowned, and dumped on a midden like that of a modern octopus. Where vertebrae in the assemblage are disarticulated, disks are arranged in curious linear patterns with almost geometric regularity. Close fitting due to spinal ligament contraction is disproved by the juxtaposition of different-sized vertebrae from different parts of the vertebral column. The proposed Triassic kraken, which could have been the most intelligent invertebrate ever, arranged the vertebral discs in biserial patterns, with individual pieces nesting in a fitted fashion as if they were part of a puzzle. The arranged vertebrae resemble the pattern of sucker discs on a cephalopod tentacle, with each amphicoelous vertebra strongly resembling a coleoid sucker. Thus the tessellated vertebral disc pavement may represent the earliest known self‑portrait.
McMenamin anticipates that this theory will be met with skepticism, as the fleshy body of a giant Triassic octopus wouldn't fossilize well. But the possibility of finding that which is essentially a gargantuan mollusk's macaroni illustration? That's the kind of glorious crazy you hope is reality.
[Via The Geological Society of America. Top artwork via Cyril Van Der Haegan/Deviantart]