By Henry Workman
Marine Science Today Writer
Between 245 and 90 million years ago a large, fish-like reptile called the ichthyosaur dominated the Mesozoic ocean at the top of the food chain. It’s unlikely that the ichthyosaur had any predators of its own, which makes a paleontological site in Nevada containing fossil remains of several individuals an ongoing mystery. Theories on the animals’ cause of death have included toxic plankton blooms or being stranded in shallow water, but Dr. Mark McMenamin of Mount Holyoke College has recently presented a more unique, if controversial, interpretation. He hypothesizes the existence of an as-of-yet undiscovered giant cephalopod, not unlike the kraken of Scandinavian folklore. According to Dr. McMenamin, the species may have grown to lengths as great as 30m (100ft) and possessed a great intelligence.
Speculation on how the ichthyosaurs met their fate has continued for decades since the remains were discovered. There has been no scientific consensus, and evidence in favor of the most popular theories has recently been complicated by new findings, which suggest the area was probably in much deeper water than previously assumed.
McMenamin’s reasoning is based primarily on perceived similarities between known cephalopod behaviors and the unusual circumstances of 9 fossilized ichthyosaurs. The skeletons somehow ended up in close proximity to one another, despite analysis indicating that each died at a different time, and therefore not by an isolated event. Also, to McMenamin, their arrangement seems too orderly to have occurred naturally. Modern octopi, some of which have exhibited a relatively high level of intelligence, have been known to use the bones of their prey to create structures known as middens. There is also anecdotal evidence of them attacking large prey such as sharks.
There’s reason to believe the organism would only leave indirect evidence of its existence. “It’s the perfect Triassic crime because octopuses are mostly soft-bodied and don’t fossilize well,” claims wife and fellow researcher Dianna Schulte-McMenamin.
Potential behaviors of the creature that would connect it to the fossil site are presented in a press release from The Geological Society of America: “The proposed Triassic kraken, which could have been the most intelligent invertebrate ever, arranged the vertebral discs in double line patterns, with individual pieces nesting in a fitted fashion as if they were part of a puzzle.” Regarding the method of attack, McMenamin suggests: “It was either drowning them or breaking their necks.”
Of course, no such theory lacking hard evidence is likely to get far without drawing intense contention from the scientific community. Few working in related fields are convinced that McMenamin’s evaluation amounts to anything more than speculation. In particular, his claim that the arrangement of ichthyosaur vertebrae, which resemble suction cups is shape, may be an example of “the earliest known self portrait,” is under fire. However, the professor, whose career bears a long list of past successes, remains optimistic about the fate of his theory. In response to the piling disbelief, he says “We’re ready for this. We have a very good case.”
Copyright © 2011 by Marine Science Today, a publication of OceanLines LLC.