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Did a sea monster make an artwork… out of bones?

Oct. 10, 2011
Courtesy of the Geological Society of America
and World Science staff

In one of the strang­est the­o­ries to find its way out of the staid world of pa­le­on­tol­ogy in a long time, re­search­ers claim a gi­gantic pre­his­tor­ic oc­to­pus may have made a jigsaw-puz­zle-like art­work out of its vic­tims’ bones.

As if that weren’t enough to raise eye­brows, there is more. Ac­cord­ing to the the­o­ry, the vic­tims were not just an­y­one, but gi­ant sea mon­sters in their own right—a trib­ute to the truly stag­ger­ing size of the sticky as­sail­ant.

Fossilized shon­i­saur ver­te­brae at Ber­lin-Ich­thy­o­saur State Park in Ne­va­da. (Cour­te­sy Mark Mc­Me­na­min)


Had enough? But there is even more. The art­work was, it would seem, not just any old doo­dle, but a sort of Tri­as­sic self-portrait.

A husband-and-wife re­search team is pre­sent­ing the pro­pos­al to ex­plain the neat, al­most sys­tem­at­ic ar­range­ment of bones in a sea rep­tile fos­sil that has puz­zled sci­en­tists for over half a cen­tu­ry. 

“We’re ready” for the skep­ti­cal ques­tion­ing to beg­in, said ge­ol­o­gist and pa­le­on­tol­ogist Mark Mc­Me­na­min of Mount Hol­yoke Col­lege in Mas­sa­chu­setts, who con­ducted the new re­search with his wife, Di­anna Schulte-Mc­Me­na­min, al­so of the col­lege.

They ad­mit their case is cir­cum­stant­ial, but they point to ev­i­dence in­clud­ing mod­ern cases of oc­to­puses kill­ing sharks; var­i­ous feats of oc­to­pus in­tel­li­gence; the fact that oc­to­puses com­monly leave piles of shells and bones in their dens from con­sumed prey; and the ob­serva­t­ion that they some­times ma­ni­pu­late such re­mains. 

They are pre­sent­ing their pro­pos­al Oct. 10 at the an­nu­al meet­ing of the Ge­o­log­i­cal So­ci­e­ty of Amer­i­ca in Min­ne­ap­o­lis.

Around 200 mil­lion to 250 mil­lion years ago, the so-called Tri­as­sic pe­ri­od, pred­a­to­ry, dinosaur-like rep­tiles called ichthyosaurs prowled the oceans. Nine fos­sils of these beasts, about as long as school bus­es, lie at Ber­lin-Ich­thy­o­saur State Park in Ne­vada. 

They have a long his­to­ry of per­plex­ing re­search­ers, in­clud­ing the world’s ex­pert on the site, the late Charles Lew­is Camp of the Uni­vers­ity of Cal­i­for­nia at Berke­ley. “Camp puz­zled over these fos­sils in the 1950s,” said Mc­Me­na­min. “In his pa­pers he keeps re­fer­ring to how pe­cu­liar this site is. We agree—it is pe­cu­liar.” 

Camp spec­u­lat­ed that the beasts had died from an ac­ci­den­tal strand­ing or a tox­ic plank­ton bloom. But these sce­narios are ass­o­ciated with shal­low water, and more re­cent work on the sur­round­ing rocks sug­gests the water was deep, Mc­Me­na­min notes.

When Mc­Me­na­min and his daugh­ter vis­ited the fos­sils at the re­mote state park, “it be­came very clear that some­thing very odd was go­ing on,” said Mc­Me­na­min. “It was a very odd con­figura­t­ion of bones.” Ev­i­dence sugg­ested the shon­isaurs weren’t all bur­ied at the same time, he said. More strange­ly, it looked like the bones had been pur­pose­fully re­ar­ranged. That got him think­ing about a mod­ern pred­a­tor known for this sort of in­tel­li­gent ma­nipula­t­ion of bones. “Mod­ern oc­to­pus will do this,” Mc­Me­namin said.

Mc­Me­namin likens the pro­posed an­cient oc­to­pus to the leg­end­ary “krak­en,” an oc­to­pus-like sea mon­ster with arms the length of ships and claimed to have prowled off the coast of Nor­way in the 1750s. The pre­his­tor­ic an­i­mal must have been twice the length of the shon­isaurs to kill them, he con­tends.

In the fos­sil bed, some of the shon­isaur ver­te­brae are ar­ranged in cu­ri­ous pat­terns with al­most ge­o­met­ric reg­u­lar­ity, Mc­Me­namin not­ed: the ver­te­brae are in dou­ble line pat­terns, with pieces nest­ing in a fit­ted way as though part of a puz­zle. 

The pro­posed Tri­as­sic kra­ken “could have been the most in­tel­li­gent in­ver­te­brate ev­er,” say the re­search­ers in their re­port. Even creep­i­er: The ar­ranged ver­te­brae re­sem­ble the pat­tern of suck­er discs on an oc­to­pus ten­ta­cle, with each ver­te­bra strongly re­sem­bling a suck­er. In oth­er words, the ver­te­bral disc “pave­ment” seen at the state park “may rep­re­sent the ear­li­est known self por­trait,” the re­port adds.

Could an oc­to­pus really have tak­en out such huge pred­a­to­ry rep­tiles? No one would have be­lieved it un­til the Se­at­tle Aquar­i­um set up a vi­deocam­era at night a few years ago to find out what was kill­ing the sharks in one of their tanks, Mc­Me­namin ar­gues. The aquar­i­um staff was shocked to learn an oc­to­pus was the cul­prit. Vi­deo of one of these at­tacks is on­line.

The “Tri­as­sic kra­ken” was probably “do­ing the same thing,” said Mc­Me­namin. Among the pieces of ev­i­dence, he adds, are many more ribs bro­ken in the shon­isaur fos­sils than would seem ac­ci­dents could explain, and a large num­ber of twisted necks. “It was ei­ther drown­ing them or break­ing their necks,” he adds, re­mark­ing on how the sup­posed kill­ings might have been car­ried out.

Of course, it’s the per­fect Tri­as­sic crime be­cause oc­to­puses are mostly soft-bodied and don’t fos­silize well. Only their small mouth parts are hard. So there is no physical evid­ence of an at­tack­er. But Mc­Me­na­min said he is­n’t wor­ried: “we have a very good case.”


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In what must be one of the strangest theories to find its way out of the staid world of paleontology in a long time, researchers claim a gigantic octopus millions of years ago may have made a jigsaw-puzzle-like artwork out of its victims’ bones. As if that weren’t enough to raise eybrows, there is more. According to the theory, the victims were not just anyone, but giant sea monsters in its own right—a tribute to the truly staggering size of the sticky assailant. Had enough? But there is even more. The artwork was, it would seem, not just any old doodle, but a sort of Triassic self-portrait. A husband-and-wife research team is presenting the proposal to explain the neat, almost systematic arrangement of bones in a sea reptile fossil that has puzzled scientists for over half a century. “We’re ready” for the skeptical questioning to begin, said geologist and paleontologist Mark McMenamin of Mount Holyoke College in Massachusetts, who conducted the new research with his wife, Dianna Schulte-McMenamin, also of the college. They admit their case is circumstantial, but they point to evidence including modern cases of octopuses killing sharks; various feats of octopus intelligence; the fact that octopuses commonly leave piles of shells and bones in their dens from consumed prey; and the observation that they sometimes manipulate such remains. They are presenting their proposal Oct. 10 at the annual meeting of the Geological Society of America in Minneapolis. Around 200 million to 250 million years ago, the so-called Triassic period, predatory, dinosaur-like reptiles called ichthyosaurs prowled the oceans. Nine fossils of these beasts, about as long as school buses, lie at Berlin-Ichthyosaur State Park in Nevada. They have a long history of perplexing researchers, including the world’s expert on the site, the late Charles Lewis Camp of the University of California at Berkeley. “Camp puzzled over these fossils in the 1950s,” said McMenamin. “In his papers he keeps referring to how peculiar this site is. We agree—it is peculiar.” Camp speculated that the beasts had died from an accidental stranding or a toxic plankton bloom. But no one has proven the water was shallow, and more recent work on the surrounding rocks suggest it was deep, McMenamin notes. When the McMenamin and his daughter visited the fossils at the remote state park, “it became very clear that something very odd was going on,” said McMenamin. “It was a very odd configuration of bones.” Evidence sugested the shonisaurs weren’t all buried at the same time, he said. More strangely, it looked like the bones had been purposefully rearranged. That it got him thinking about a modern predator known for this sort of intelligent manipulation of bones. “Modern octopus will do this,” McMenamin said. McMenamin likens the proposed ancient octopus to the legendary “kraken,” an octopus-like sea monster with arms the length of ships and claimed to have prowled off the coast of Norway in the 1750s. The prehistoric animal must have been twice the length of the shonisaurs to kill them, he contends. In the fossil bed, some of the shonisaur vertebral disks are arranged in curious patterns with almost geometric regularity, McMenamin noted: the vertebral discs are in double line patterns, with individual pieces nesting in a fitted way as though part of a puzzle. The proposed Triassic kraken “could have been the most intelligent invertebrate ever,” say the researchers in their report. Even creepier: The arranged vertebrae resemble the pattern of sucker discs on an octopus tentacle, with each vertebra strongly resembling a sucker. In other words, the vertebral disc “pavement” seen at the state park “may represent the earliest known self portrait,” the report adds. Could an octopus really have taken out such huge predatory reptiles? No one would have believed it until the Seattle Aquarium set up a video camera at night a few years ago to find out what was killing the sharks in one of their tanks, McMenamin argues. The aquarium staff was shocked to learn an octopus was the culprit. Video of one of these attacks can be found online by using the search terms “shark vs octopus.” The “Triassic kraken” was probably “doing the same thing,” said McMenamin. Among the pieces of evidence, he adds, are many more ribs broken in the shonisaur fossils than would seem accidental and the twisted necks. “It was either drowning them or breaking their necks.” Of course, it’s the perfect Triassic crime because octopuses are mostly soft-bodied and don’t fossilize well. Only their mouth parts are hard. That means the evidence for the murderous Kraken is circumstantial, which may leave some scientists skeptical. But McMenamin said he isn’t worried: “we have a very good case.”