An unusual presentation at a scientific conference Monday has many paleontologists demanding: Show me the kraken!
Geologist Mark McMenamin has invoked the mythical creature from Norse mythology as an outside-the-box explanation for a puzzling assembly of marine fossils in a state park in Nevada. These fossils could actually be a carefully patterned refuse pile left by an enormous, tentacled creature, he says – a creature he dubs a kraken.
The problem, other researchers say, is that neither Nevada's Berlin-Ichthyosaur State Park, nor any other, similar fossil assemblage around the world has yielded any direct or indirect fossil evidence of a "kraken" – let alone any 200-million to 250-million year old creature capable of arranging its dinner scraps in a pattern.
Dr. McMenamin, who teaches at Mount Holyoke College in South Hadley, Mass., presented his proposal at a Geological Society of America conference in Minneapolis on Monday. He came with flak jacket in tow.
"We're ready for this. We have a very good case," he said.
The period this proposed creature would have populated has long fascinated scientists. Known as the Triassic Period, it lasted roughly 50 million years. It began at the end of the planet's largest mass extinction some 251 million years ago. Researchers estimate that some 96 percent of all marine species and 70 percent of land-based creatures vanished. It ended in another mass extinction, one that would lead to the rise of the dinosarus.
The Triassic "is a time when modern ecosystems come into being," says Hans-Dieter Sues, curator of vertebrate paleontology at the Smithsonian's National Museum of Natural History. "Almost every group that today is dominant in the world's oceans or on land had either its first appearance in the Triassic or some of its closest relatives first showed up."
One of the period's iconic creatures: large sharp-toothed fish known as ichthyosaurs. One member in particular, Shonisaurus popularis, grew to lengths of up to 50 feet. Nevada's Berlin-Ichthyosaur State Park boasts nine fossils of these giants, all bunched in the same general location.
Random fossil pile or kraken lair?
At issue is whether the assembly represents animals who died in a shallow ocean from a mass stranding or an explosive algae bloom, or whether the formation was in the deep sea. Some recent geological analysis has suggested the deep-sea location – the modern-day battleground for sperm whales and their prey, giant squid.
Enter McMenamin and the kraken. A unique pattern of vertebra caught his attention – two rows, neatly set side by side in a manner that make them look nested. Moreover, the bones were scarred in ways that indicated the animals died at different times.
Marine scientists have long noted that octopuses gather up bones, rocks, remains of prey, literally anything they can grab in order to hide the entrances to their dens.
McMenamin explained that the bones in Nevada looked to be placed there on purpose. And the pattern of arrangements for the vertebra suggested to him a higher level of intelligence than one might expect from a mere piling of bones. One pattern of side-by-side lengths of vertebra has the look of a neatly arranged suckers on a squid's tentacle.
"I think that these things were captured by a kraken and taken to the midden" to be dismembered, McMenamin said in a prepared statement.
Without fossil evidence of a tentacled predator, however, many researchers are highly skeptical of the notion of a Triassic kraken, let alone an animal capable of its own kind of performance art.
Patterns also have random sources, notes Dr. Sues. If the Shonisaurus died in a mass stranding, for instance, their bodies could well have fallen one on top of another, allowing for the pattern to form as the bodies decomposed and the vertebra settled into place.
"I've been to Ichthyosaur State Park and I've worked in marine Triassic rocks in Nevada for a number of years," he says. The area essentially represents a mass burial ground for ichthyosaurs in a shallow sea, he says.
If it's true, how do you prove it?
Indeed, it's difficult to know how to characterize McMeniman's proposition, he says, because it's inherently untestable in the absence of fossil evidence for a kraken-like creature from the same period.
Typically, paleontologists find a creature's fossil remains first, sometimes starting with a small portion of the skeleton, then try to build a more complete picture as more bones emerge. Only then can they try to begin to piece together its life and times.
If such a creature had structures comparable to squids' beaks or the bony hooks inside some tentacle suckers, the bones at the park would show far more damage then they do, Sues says.
Paleontologist Thomas Holtz Jr. notes that McMeniman cited recent work suggesting a deep ocean, and so another explanation for the assemblage of fossils may be in order.
"Fair enough," says Dr. Holtz, who is based at the University of Maryland. "I'll go with that. It is the next step that is the giant leap: Bunch of dead ichthyosaurs, therefore giant cephalopods for which we have no evidence."
That said, he continues, one could take a closer look at the side-by-side strings of vertebra, for instance, to seen if they are lined up in the same order in which the individual bones aligned naturally.
If they do, he says, it suggests "that's just the way they fell apart." An intentional re-arrangement would likely shift the bones out of their natural order and perhaps even mix bones from different individuals.
It also would be helpful to turn to marine and soil scientists to better pin down the nature of the marine soils at the site and to see if comparable patterns of bone arrangements appear naturally when modern whales die in groups.
In the end, he says, looking at the way the fossils have been preserved and the possible causes, far simpler explanations exist for the Nevada assemblage.
In principle, it's possible that the Triassic hosted large squid- or octopus-like cephalopods, Dr. Holtz says. The fossil record does yield evidence of large squids from the Cretaceous Period, some between 65 million and 100 million years ago, he notes.
But at this point, the notion of a Triassic kraken "is too many steps away from the evidence to call it science," he says.