Sunday, October 16, 2011

The Kraken Sleepeth

Today, dear readers, we’re going to do something a little different.  Today, instead of talking about awesome, great science, we’re going to talk about bad science

I am speaking, for those of you who haven’t heard, of the Kraken story.

The story starts off in the state of Nevada, over in Berlin-Ichthyosaur State Park.  In addition to numerous attractions, the park is home to fossils of Shonisaurus, a type of ichthyosaur.  Ichthyosaurs were dolphin-like reptiles that roamed the oceans back in the time of the dinosaurs, and Shonisaurus is one of the biggest to ever have lived, growing to nearly 50 feet long.  Many of these spectacular fossils are still in the ground, where visitors to the park can go see them.

Artist's reconstruction of ichthyosaurs.

Now, a fossil site with dozens of gigantic marine reptiles is pretty amazing, as you can imagine, but the site has also had scientists confused for a while.  The big question is: how did all of those ichthyosaur skeletons get there?  In the past, scientists have proposed a few answers: the reptiles may have been beached and stranded; they may have fallen victim to some sort of poisoning and all died; or they may have been wiped out by an underwater landslide or similar catastrophic event.  All reasonable ideas.

But each of these explanations has at least one problem: in order for the ichthyosaurs to have been beached, the water would have had to be shallow, but the geology of the area seems to indicate deep water; toxicity of some kind could have killed the animals, but doesn’t explain how they all ended up in the same place, next to each other; and a catastrophic death would have killed them all at once and placed them next to each other, but the bones all appear to have decayed in different ways, implying that they didn’t all die together.  So you can see, we have a bit of a puzzle.  And to this day, the puzzle remains unsolved.

Enter Mark McMenamin, paleontologist from Mount Holyoke College.  McMenamin is familiar with the site and its perplexing fossils, and just last week at the meeting of the Geological Society of America in Minneapolis, he proposed a unique explanation.  He notes that, in addition to the confusing factors I mentioned above, a number of the fossils are arranged in a peculiar north-south orientation, almost as though they were placed there intentionally.  Strange, indeed.  It does make you wonder how the fossils could have ended up in that pattern.  Mark continues:

                “We hypothesize that the shonisaurs were killed and carried to the site by an enormous Triassic cephalopod, a “kraken,” with estimated length of approximately 30m, 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.” (from the GSA Abstract)

…Wait.  What?

Okay, yes, the existence of a giant ichthyosaur-hunting squid could explain how all of those fossils got there, and yes, that would be very cool if it were true, but what evidence is there that that’s the case?  Did you find a squid fossil?  Or perhaps the skeletons of other prey animals in the same area?  Do tell.

                “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.” (from the GSA Abstract)

I guess the vertebrae do kind of
look like a tentacle ... kind of.
Ah.  Your “evidence” of the existence of a hyper-intelligent, 100-foot long killer squid is the fact that some of the vertebrae remind you of a squid tentacle, and you figure the squid arranged them like that in an attempt to make a picture of itself. 




Alright, let’s talk about evidence.  When scientists come up with a hypothesis – an educated guess at the explanation for some phenomenon – they support their hypothesis with evidence.  Example: I hypothesize that all of the dinosaurs were killed by a giant meteor 65 million years ago, based on the following evidence: they all disappeared at roughly the same time; many other animals disappeared as well; there is a layer of ash all over the world consistent with a meteor impact; and there is an enormous crater in Mexico that is 65 million years old.  Solid hypothesis, good evidence.

McMenamin has almost no evidence for his hypothesis.  The death of these ichthyosaurs could be explained by a number of simple explanations that do not invoke the presence of a monster squid.  Now, don’t get me wrong, it is entirely possible that there was a massive killer squid and that it ate giant reptiles, after all it’s thought that giant squids today battle sperm whales in the depths of the ocean.  And yes, that would be very cool and extremely significant to paleontological science, BUT that is a wild, extreme suggestion, and if you want to support it, you’ll need tons of really convincing evidence.  All McMenamin has is a bunch of oddly-arranged vertebrae, and based on that he conjured an imaginary creature to explain them.

So Pelamis, I hear you ask, how would you go about proving the existence of a giant squid?  Well, first, I’d look for some other evidence of the presence of a squid.  Squid and octopi are extremely rare in the fossil record.  Since they have no bones, and are pretty much entirely soft and squishy, they almost never fossilize.  There are, of course, exceptions, but so far as I know, no squid fossils have been found in the Nevada bonebeds.  It’s also possible that a giant squid would leave marks on the bones of its prey as it fed on them, or on nearby rocks as it grabbed them with its enormous tentacles, but again, nothing like this has been found.  What I would find really interesting is a study on modern-day squid habits.  After all, McMenamin didn’t make up the idea of a midden – some animals, including many small mammals and yes, some octopi, store the remains of their food in a little dump called a midden.  It would be really cool to see if modern-day giant squid keep middens and if so, what their middens look like.  Then, we could compare these squid middens to the arrangement of the bones in Nevada.  But until someone follows a giant squid back home and finds out whether or not they even keep middens, we have nothing to go on. 

An octopus hanging out above his midden.
Now, what we have here is an example of an overactive imagination leading to a fairly ridiculous, pseudo-scientific story.  And you know what?  It happens.  Not a big deal, right?  Well, usually.  See, it’s okay for me to sit in my apartment and come up with all the crazy ideas I want, but when a scientist presents those unsupported ideas as fact, as though they are backed up by solid evidence, he is being irresponsible.  Because when a scientist starts telling the story of a giant prehistoric Kraken, news reporters will be very interested.  And if those news reporters decide to take that scientist’s word as true, without asking anyone else (which is equally irresponsible), then you end up with a host of news reports on the internet telling people about how scientists have discovered the “Lair of an ancient Kraken,” (see: here, here, and here) even though there is no evidence at all that this creature ever existed.  Thankfully, many sites are also discussing the problems with the hypothesis (see: here, here, and here).

So please remember, fellow science enthusiasts, take what you hear with a grain of salt.  Just because a scientist says something doesn’t mean it’s scientific fact.  When science says “We now know this!” always respond with “How do you know?”  Gather enough info to make your own decisions about the research, because while most scientific studies are valid and perfectly reasonable, some of the reports out there are just plain crazy.

Besides, there’s plenty of legitimate and fascinating fossil stories out there:
-Several weeks ago, a fossil of a plesiosaur (another type of extinct, giant marine reptile) was found to be pregnant! This is ground-breaking, since it’s evidence that these reptiles gave live birth, as opposed to laying eggs like most reptiles. 

-And just a couple of weeks ago, Science reported online that researchers had discovered cave drawings in France that seem to have been made by cavemen children.  In the spirit of today’s post, I’ll admit I’m a little skeptical about some of these researcher’s inferences, but I’ll let you decide for yourself.  In any case, cave paintings by children are pretty cool! 

The North Pacific Giant Octopus - the real-life Kraken.

2 comments:

  1. I subscribed to this blog a while ago, I think because my friend Eric suggested it on facebook? I really enjoyed this post; I wonder what really caused the pile of fossils. I am pretty sure it is not a kraken self-portrait...

    I also really liked the links about the cave children drawings and pregnant plesiosaur. Though, I get what you mean about being skeptical about some of the inferences made about the children's drawings. How on earth can they tell the children's genders by the shape of their fingers??

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  2. Thanks for the support!
    About the cave children: According to one site I looked at, the researchers got a large sample of adults and children to recreate finger drawings in clay, and compared these finger drawings to the cave drawings.

    '"By measuring the width of your three middle fingers, you can actually get a very individualized number," Cooney says. "People who had a measurement of 34 mm or less are actually children who are 7 years old or younger,"'

    It sounds like those same measurements allow them to differentiate boys and girls, though I still wonder exactly how accurate that method is. The articles I read present it pretty confidently, but then, so do a lot of those Kraken articles.

    http://www.pri.org/stories/science/stone-age-cave-drawings-made-by-children6238.html

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