The titan

One thing science teaches us is that just about everything is interesting if you look at it carefully enough.  Still, there's an ingrained human tendency to be overawed by superlatives -- the biggest, the heaviest, the brightest, the strongest, the most powerful.

It's why a recent fossil discovery from Somerset, England has made the headlines.  The rocks in Somerset, in the southwest of England, are mostly of Triassic age; it's not far from the famous "Jurassic Coast," which begins around Exmouth with Triassic sedimentary rocks that gradually become younger as you head west.  It's the site that the brilliant nineteenth century paleontologist Mary Anning studied -- becoming one of a very long list of talented women scientists who struggled for recognition by their male peers with tragically little success.

Somerset, which is a bit north from there, is also a great site for Mesozoic fossils, and some amateur fossil hunters recently found a doozy.  Father-and-daughter team Justin and Ruby Reynolds were searching along the north Somerset coast and saw what turned out to be a fossilized jawbone...

... of a creature which is estimated to have been twenty-five meters long.  (For my fellow Americans, twenty-five meters is about 130 bananas long.)

The animal was a type of ichthyosaur, a group that reached their height of diversity in the late Triassic Period.  We've known for a long time that ichthyosaurs were bizarre animals.  They were streamlined predators that look remarkably like dolphins, although they are only distantly related (making the two groups a great example of convergent evolution).  A number of them had an even stranger feature, which is the largest eye-diameter-to-body-size ratio of any animal known -- the well-named Ophthalmosaurus (Greek for "eye lizard") was six meters long and had eyes the size of basketballs.

But this new species could have eaten an Ophthalmosaurus as an appetizer and still had plenty of room for the entrée.  It's been dubbed Ichthyotitan severnensis -- more or less, "gigantic fish-thing from the Severn."  The fossil dates to about 202 million years ago.

[Image credit: artist Sergey Krasovskiy]

"I was highly impressed that Ruby and Justin correctly identified the discovery as another enormous jawbone from an ichthyosaur," said Dean Lomax, paleontologist at the University of Manchester, who verified the find and helped to classify it, in an interview with Science Daily.  "They recognized that it matched the one we described in 2018. I asked them whether they would like to join my team to study and describe this fossil, including naming it.  They jumped at the chance.  For Ruby, especially, she is now a published scientist who not only found but also helped to name a type of gigantic prehistoric reptile.  There are probably not many fifteen-year-olds who can say that!  A Mary Anning in the making, perhaps."

The Ichthyotitan, though, was one of the last of its kind; it, and a great many other species, were victims of the Late Triassic Mass Extinction, a poorly-understood extinction event that occurred around 201 million years ago and was only slightly smaller than the much better-known Cretaceous-Tertiary Extinction that would happen 135 million years later.  The most likely explanation of the Late Triassic event is volcanism and outgassing from the Central Atlantic Magmatic Province, the mantle upwelling from which would ultimately split up Pangaea and open the Atlantic Ocean, but that point is still being argued over by geologists and paleontologists.

Whether this particular Ichthyotitan was killed during the extinction event itself is, of course, impossible to tell, but the fossil dates to almost exactly the right time.  Its discovery also ramps up the search for more fossils along the north Somerset coast.  "It is quite remarkable to think that gigantic, blue whale-sized ichthyosaurs were swimming in the oceans around what was the UK during the Triassic Period," Lomax said.  "These jawbones provide tantalizing evidence that perhaps one day a complete skull or skeleton of one of these giants might be found.  You never know."

It's a hell of a find -- a bone from a creature in contention for the largest animal known.  I don't know about you, but it's hard even to imagine a predator that big.  The late Triassic must have been an impressive-looking place...

... observed, of course, from a safe distance.

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A new view of the "eye lizard"

I am forever astonished at the level of detail we can infer from fossils that are hundreds of millions of years old.

The most recent example of this came from analysis of a fossil of Stenopterygius, an ichthyosaur that lived during the Jurassic Period (this particular fossil has been dated to about 180 million years ago).  We usually think of fossils as preserving bones and teeth, and occasionally impressions of scales or skin or feathers -- but this one was so finely preserved that researchers have been able to make some shrewd inferences about color, metabolism, and the structure of soft tissues.

Artist's conception of Stenopterygius [Image licensed under the Creative Commons Nobu Tamura (http://spinops.blogspot.com), Stenopterygius BW, CC BY-SA 3.0]

We've known for a long time that ichthyosaurs are bizarre animals. They were streamlined predators that look remarkably like dolphins, although they are only distantly related (making the two groups a great example of convergent evolution).  A number of them had an even stranger feature, which is the largest eye-diameter-to-body-size ratio of any animal known -- the well-named Ophthalmosaurus (Greek for "eye lizard") was six meters long and had eyes the size of basketballs.

Stenopterygius was a bit smaller, with an average adult size of four meters.  But up until recently, all we've been able to do is speculate on what it might have looked like, and how it behaved.  A discovery in Germany, described in a paper in Nature called "Soft-Tissue Evidence for Homeothermy and Crypsis in a Jurassic Ichthyosaur" and authored by no fewer than 23 scientists, has given us incredibly detailed information on these oddball dinosaurs.

The authors write:

Ichthyosaurs are extinct marine reptiles that display a notable external similarity to modern toothed whales.  Here we show that this resemblance is more than skin deep.  We apply a multidisciplinary experimental approach to characterize the cellular and molecular composition of integumental tissues in an exceptionally preserved specimen of the Early Jurassic ichthyosaur Stenopterygius.  Our analyses recovered still-flexible remnants of the original scaleless skin, which comprises morphologically distinct epidermal and dermal layers.  These are underlain by insulating blubber that would have augmented streamlining, buoyancy and homeothermy.  Additionally, we identify endogenous proteinaceous and lipid constituents, together with keratinocytes and branched melanophores that contain eumelanin pigment.  Distributional variation of melanophores across the body suggests countershading, possibly enhanced by physiological adjustments of colour to enable photoprotection, concealment and/or thermoregulation.  Convergence of ichthyosaurs with extant marine amniotes thus extends to the ultrastructural and molecular levels, reflecting the omnipresent constraints of their shared adaptation to pelagic life.

So from a 180-million-year-old fossil, we now know that Stenopterygius (1) was a homeotherm (colloquially called "warm-blooded"), (2) had a blubber layer much like modern dolphins and whales, and (3) were countershaded -- dark on top and light underneath, to aid camouflage -- similar to dozens of species of modern fish.

This level of preservation is extremely unusual.  "Both the contour of the body and the remains of internal organs are clearly visible," said paleontologist Johan Lindgren of the University of Lund, who co-authored the paper.  "Surprisingly, the fossil is so well preserved that it is possible to observe individual cell layers inside the skin."

"This is the first direct chemical evidence of warm blood in an ichthyosaur, because a subcutaneous fat layer is a characteristic of warm-blooded animals," said Mary Schweitzer of North Carolina State University, also a co-author.  "Ichthyosaurs are interesting because they have many features in common with dolphins, but they are not related at all to these mammals that inhabit the sea.  But the enigma does not stop there...  They have many characteristics in common with living marine reptiles, such as sea turtles; but we know from the fossil record that they gave live birth to their young...  This study reveals some of those biological mysteries."

Which is pretty astonishing.  I've always had a fascination for the prehistoric world, and have spent more time than I like to admit wondering what it might have been like to live in the Jurassic world. This research gives us one more piece of information -- about a fierce prehistoric predator that shared some amazing similarities to creatures that still swim in our oceans.

****************************************

A new view of the "eye lizard"

I am forever astonished at the level of detail we can infer from fossils that are hundreds of millions of years old.

The most recent example of this came from analysis of a fossil of Stenopterygius, an ichthyosaur that lived during the Jurassic Period (this particular fossil has been dated to about 180 million years ago).  We usually think of fossils as preserving bones and teeth, and occasionally impressions of scales or skin or feathers -- but this one was so finely preserved that researchers have been able to make some shrewd inferences about color, metabolism, and the structure of soft tissues.

Artist's conception of Stenopterygius [Image licensed under the Creative Commons Nobu Tamura (http://spinops.blogspot.com), Stenopterygius BW, CC BY-SA 3.0]

We've known for a long time that ichthyosaurs are bizarre animals.  They were streamlined predators that look remarkably like dolphins, although they are only distantly related (making the two groups a great example of convergent evolution).  A number of them had an even stranger feature, which is the largest eye-diameter-to-body-size ratio of any animal known -- the well-named Ophthalmosaurus (Greek for "eye lizard") was six meters long and had eyes the size of basketballs.

Stenopterygius was a bit smaller, with an average adult size of four meters.  But up until recently, all we've been able to do is speculate on what it might have looked like, and how it behaved.  A discovery in Germany, described in a paper in Nature called "Soft-Tissue Evidence for Homeothermy and Crypsis in a Jurassic Ichthyosaur" and authored by no fewer than 23 scientists, has given us incredibly detailed information on these oddball dinosaurs.

The authors write:

Ichthyosaurs are extinct marine reptiles that display a notable external similarity to modern toothed whales.  Here we show that this resemblance is more than skin deep.  We apply a multidisciplinary experimental approach to characterize the cellular and molecular composition of integumental tissues in an exceptionally preserved specimen of the Early Jurassic ichthyosaur Stenopterygius.  Our analyses recovered still-flexible remnants of the original scaleless skin, which comprises morphologically distinct epidermal and dermal layers.  These are underlain by insulating blubber that would have augmented streamlining, buoyancy and homeothermy.  Additionally, we identify endogenous proteinaceous and lipid constituents, together with keratinocytes and branched melanophores that contain eumelanin pigment.  Distributional variation of melanophores across the body suggests countershading, possibly enhanced by physiological adjustments of colour to enable photoprotection, concealment and/or thermoregulation.  Convergence of ichthyosaurs with extant marine amniotes thus extends to the ultrastructural and molecular levels, reflecting the omnipresent constraints of their shared adaptation to pelagic life.

So from a 180-million-year-old fossil, we now know that Stenopterygius (1) was a homeotherm (colloquially called "warm-blooded"), (2) had a blubber layer much like modern dolphins and whales, and (3) were countershaded -- dark on top and light underneath, to aid camouflage -- similar to dozens of species of modern fish.

This level of preservation is extremely unusual.  "Both the contour of the body and the remains of internal organs are clearly visible," said paleontologist Johan Lindgren of the University of Lund, who co-authored the paper.  "Surprisingly, the fossil is so well preserved that it is possible to observe individual cell layers inside the skin."

"This is the first direct chemical evidence of warm blood in an ichthyosaur, because a subcutaneous fat layer is a characteristic of warm-blooded animals," said Mary Schweitzer of North Carolina State University, also a co-author.  "Ichthyosaurs are interesting because they have many features in common with dolphins, but they are not related at all to these mammals that inhabit the sea.  But the enigma does not stop there...  They have many characteristics in common with living marine reptiles, such as sea turtles; but we know from the fossil record that they gave live birth to their young...  This study reveals some of those biological mysteries."

Which is pretty astonishing.  I've always had a fascination for the prehistoric world, and have spent more time than I like to admit wondering what it might have been like to live in the Jurassic world.  This research gives us one more piece of information -- about a fierce prehistoric predator that shared some amazing similarities to creatures that still swim in our oceans.

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One of the best books I've read recently is Alan Weisman's The World Without Us.  I wouldn't say it's cheerful, however.  But what Weisman does is to look at what would happen if the human race was to disappear -- how long it would take for our creations to break down, for nature to reassert itself, for the damage we've done to be healed.

The book is full of eye-openers.  First, his prediction is that within 24 hours of the power going out, the New York Subways would fill with water -- once the pumps go out, they'd become underwater caves.  Not long thereafter, the water would eat away at the underpinnings of the roads, and roads would start caving in, before long returning Manhattan to what it was before the Europeans arrived, a swampy island crisscrossed by rivers.  Farms, including the huge industrial farms of the Midwest, would be equally quick; cultivated varieties of wheat and corn would, Weisman says, last only three or four years before being replaced by hardier species, and the land would gradually return to nature (albeit changed by the introduction of highly competitive exotic species that were introduced by us, accidentally or deliberately).

Other places, however, would not rebound quickly.  Or ever.  Nuclear reactor sites would become uninhabitable for enough time that they might as well be considered a permanent loss.  Sites contaminated by heavy metals and non-biodegradable poisons (like dioxins) also would be, although with these there's the possibility of organisms evolving to tolerate, or even break down, the toxins.  (No such hope with radioactivity, unfortunately.)

But despite the dark parts it's a good read, and puts into perspective the effect we've had on the Earth -- and makes even more urgent the case that we need to put the brakes on environmental damage before something really does take our species out for good.

Breaking news: precision matters.

I keep telling myself not to expect much from how science is covered in commercial media.  They are beholden to sponsors, who pay attention to only one thing; how many people partake.  So if media can get more sponsors (= more money) by sensationalizing scientific news, that's what they do, however it misleads the gullible and undermines the reputation of science as a whole.

I guess I just thought that National Geographic would be above that kind of thing.

Yes, National Geographic, that venerable institution that sends out the monthly glossy, yellow-edged magazine that from its density appears to be printed on sheets of lead.  That wonderful source of information and photographs from exotic locales that teenage boys the world over peruse in the hopes of seeing a topless native woman.  Yes, National Geographic.  Even they have succumbed.

I came to this realization when I was perusing the News section of the online National Geographic, and I saw the headline, "New Sea Monster Found, Rewrites Evolution?"  It happens that this particular turn of phrase is one that really grinds my gears -- it seems like every time some paleontologist finds a new fossil, the media shrieks that it's going to "rewrite everything we know about evolution!"  And, of course, it never does.  Given that what we have from the fossil record represents a tiny percentage of the living things the Earth has seen during it's three-odd-billion-year hosting of life, it's only to be expected that we'll find new and amazing things in fossil beds, more often than not.  And surprisingly, astonishingly, the evolutionary model has survived, intact, despite all that "rewriting."

Now, to be fair, this discovery was pretty cool -- a new species of ichthyosaur, Malawania anachronus, so named because it dates to 66 million years after its nearest cousins were supposedly extinct.  But like I said: this is interesting, but hardly earthshattering.  A group of seagoing prehistoric carnivores were still around more recently than scientists thought.  No "rewriting of evolution" necessary.

Also, must they always call them "sea monsters?"

Now, you may well think I'm overreacting, here.  But cut me some slack; given that I'm a biologist, it's to be expected that precision in speech on this particular topic is something I value.  But seriously, you may be saying; does anyone take that "rewriting evolution" thing as more than hyperbole?

You have only to look at the comments section on the article in question to see that the answer is "yes."

"As most scientists now know who are brave enough to admit it, the entire 'theory' of evolution needs to be rewritten," said one commenter.  "As long as we try to cover up its many problems, we are the problem."

"Evolved animals 'appear' in the Jurassic or whatever period...I guess out of nowhere," wrote another.  "As if by magic without numerous specimens leading to the found fossil.  You would think that life on earth after 3 billion years of evolution would look like the 'Island of Doctor Moreau' of blended animals."

One person, at least, tried to bring some sense into the discussion.  "Oh come on, National Geographic, pul-eezzze stop using the word 'monster' in your headlines to suck in readership," he wrote.  "That's tabloid journalism, and National Geographic should know better.  A ten-foot long aquatic reptile is not a 'monster' in any sense of the word.  This animal was a sleek, efficient predator of fish and has many characteristics of already-discovered fossils of similar animals.  And while it may ADD valuable information to our understanding of how evolution has worked, it will NOT 'rewrite evolution' as the headline further claims.  That would seem to shred Charles Darwin's masterpiece of science, and is plainly not what's happening here. "

Unfortunately,  he was immediately shouted down.  "Stop whining," one person responded.  " If you don't like the headlines here, go elsewhere and complain."  Another said, "So, you are complaining about how they try to suck in readers with the word monster, yet you were here, reading this article. Think ahead before you comment mouse brain."

Herein lies the problem, and it's not just an issue of civil discourse.  Precision matters, especially when writing about topics that are, by their very nature, controversial.  I'm guessing that the author of the piece, Christine Dell'Amore, had no intention of giving fuel to the fire of the creationists -- but what are the anti-evolution crowd supposed to think, when every other week there's an article with the headline, "Evolution Has To Be Rewritten?"  However much I lambast them for their anti-science, anti-rational stance, you have to admit that anyone would begin to wonder about a scientific model that has to be "rewritten" every time some tiny new piece of evidence is found.

Okay, I'm ranting.  But really, it's National Geographic.  I expect better from them.  I've completely written off the Discovery network, for example, which has just announced that ANIMAL PLANET'S MONSTER WEEK BEGINS TODAY.  (Capitalization theirs.)  And despite the fact that to a biologist, the word "animal" means "a type of real, live creature, i.e. not fictional," they are going to kick off the week with a special about...

... mermaids.

Just 'scuse me while I go pound my forehead on the desk.