The most common question any paleontologist ever gets asked has also been, historically, the one with the least satisfying answer. When faced with it, many launch into an explanation of how colors don’t fossilize, the mechanics of reconstructing animals from the bones up, the idea of drawing from related or convergent species. Others, more taciturn, simply say “We don’t know.”

For the most part, that edict still stands. When gazing into the eye sockets of the mighty Tyrannosaurus rex, or staring in awe at the jumble of Triceratops, Stegosaurus, and Apatosaurus that litter our institutions like lions in a zoo, we must simply throw up our hands and say in essence, “We don’t know what color they are, and likely never will.”

It’s part of the mystery of dinosaurs. To such visual creatures as Homo sapiens, the lack of color in dinosaurs is a driving bit of their mystique. How strange these creatures must be, if we cannot tell even their patterns and hues with certainty!

And then…this happened.

Sinosauropteryx Colors, by Asher Elbein

In a frankly stunning one-two punch, two separate teams of scientists broke a color barrier that’s been in place for millions of years. The first team, Led by University of Bristol’s Mike Benton, used electron microscopes to scan the preserved feathers of the tiny Sinosauropteryx and concluded that the tail and portions of the body were covered in ginger hued fluff, as well as white rings that adorned the tail.

Anchiornis color scheme

Only weeks later, the second team did them one better. Where Benton’s team had gotten a fairly good glimpse at bits of feathers, they hadn’t seen the color scheme of the entire animal. Dr. Prum’s team, on the other hand, had. Analyzing a little protobird known as Anchiornis, Prum and his colleagues found that it was patterned like a pileated woodpecker (and thus proving that what’s black, white, and red all over is neither newspaper nor unfortunate zebra, but a dinosaur.)

This is all very exciting, but what’s really interesting is how this was all found out. It turns out that there are microscopic structures in feathers called melanosomes. Melanosomes come in all kinds of different shapes, and each shape codes for a different color. Knowing this, the scientists analyzed the preserved feathers of Sinosauropteryx and Anchiornis for melanosomes, and to their delight they found them. From there it was a (relatively) simple task to decode the colors of the animals. The discovery also had the happy side effect of proving, more or less once and for all, that the preserved feathers were exactly that, not artifacts in the rock or collagen fibers as some had posited.

So what now? A door has opened before us, one thought to be locked forever. Any feathered dinosaur can be analyzed this way, as long as its melanosomes are sufficiently well preserved. A new and exciting oppurtunity has opened up before us. But as for dinosaurs will scaly skin, the prospects are a bit more mixed. It’s not not clear that the same processes that analyze feathers can be made to work for skin impressions, especially those of scales. But who knows? Perhaps one day we will know for certain what colors even beasts like Tyrannosaurus were.

Here is a Cretaceous mystery.

Three different species of dinosaur are found in one filled-in pit. They are well preserved, although the method by which it happened is unknown. It’s not a “whodunit”, but a “what-dunit.”  There are clues as to the case, though. And they can be unlocked.

First a quick question: Where do fossils come from? For the most part, the recipe for a fossil is fairly simple. Take one or more dead animals (or, more rarely, traces of it such as skin impressions or footprints.) Place the carcasses in conditions that allow for good preservation.  Silt is good, if you can get it.  So are volcanic eruptions or poorly oxygenated sea-floors.  Let the sediment harden, let the bones mineralize and turn to rock. Allow for a bake time of anywhere from 1 million to 4.5 billion years.  Et Viola!

It may sound cut-and-dried, but it’s not. The necessary conditions for fossilization can arise in strange places.  Clearly something like that has happened here. In the spirit of a good detective novel, lets put forth all of the known evidence before we begin.

Fact 1: The dinosaurs found are Limusaurus, a turkey-like herbivore, and Gaunlong, a wolf sized predator. Both are bipeds. There are two of each in the bone bed.

Fact 2: The bodies are stacked one on top of another in the bone bed. Their carcasses are contorted and wonderfully preserved. Clearly, all did not die at once.

Fact 3: The rock in which they were found is a mix of volcanic mudstone, ash, and sandstone. The sandstone indicates a wet, marshy environment. The volcanic ash and mudstone indicates hard crusts of ash and ash churned mud.

Fact 4: The bone-bed itself is shaped in a column-like pit.

Fact 5: There are sauropods in this ecosystem. Big ones.

Taking these facts together, what scenario can be extrapolated? David Eberth and colleagues think that they’ve found the answer, and they’re publishing it in the February edition of PALEOS. Analyzing the facts on hand, they’ve come up with a very likely scenario.

Let’s set the scene. It’s the late Jurassic, over 160 million years ago. The stage is a floodplain that’s slipping into marshland. Puddles and bogs dot the landscape in a clogged mess of horsetail and ferns. Volcanic activity is fairly common; this particular plain has been showered with ash at some point in the past. Now the ash has hardened and plants are growing once more.

A Mamenchiosaurus moves across the bog. It’s a massive sauropod dinosaur, 69 feet long, weighing several tons, with a staggeringly long neck and whip-like tail. As it moves the ground gives way with bubbling squelches under its massive feet. It sinks up to its knees in soupy muck. But it’s a strong animal, and it’s able to pull itself along through the marsh until it reaches firmer ground. Behind it, something rather interesting has happened. The volcanic mudstone has broken under the beast’s weight. The moist soil underneath is saturated with water, and the footprints backfill with quicksand. For all intents and purposes, the marsh looks undisturbed.

Some time passes. A flock of Limusaurus wander through the floodplain, grazing. They’re much smaller then the Mamenchiosaurus. In fact, they’re under 40 pounds and not much longer then a big dog: far too light to break the thick crust of ash. As they nibble, one of them slips and becomes mired in the thick mud. Like most theropods, it uses its hind legs to move and has small arms. When it falls in the mud, it is trapped. Eventually its weight pulls it down and it drowns. Another Limusaurus is trapped as well. A few days later, a Gaunlong arrives, attracted by the scent of putrefying meat, and it too is trapped. Another, larger Gaunlong investigates. Into the pit it goes.

Rinse, Stir, Repeat.

Eventually, the pit trap is filled with dead animals. Those that stumble in now can get out. Quadrapedal herbivores don’t get caught; they can use both forelimbs and hind limbs to clamber out without much trouble.

Time passes. The mud and carcasses congeal and are covered by successive floods and ash falls. Eventually, they become fossils.

This kind of analysis is part and parcel of Paleontology. Using clues preserved at the scene, scientists can make fairly plausible guesses about the nature of their finds. Of course, we can rarely know for certain exactly what happened. This entire scenario might well be wrong, and perhaps some new bit of evidence will arise to throw it out. But for now, David Eberth and co. have done a first class bit of paleontological detective work. And they have provided something more magical: A spark for the imagination.

And that, of course, is what the best fossils (and detective stories) do.

]]> http://thefastertimes.com/dinosaurs/2010/01/26/cretaceous-csi-footprints-of-death/feed/ http://thefastertimes.com/dinosaurs/2010/01/13/avatar-and-the-riddle-of-the-space-dinosaurs/ http://thefastertimes.com/dinosaurs/2010/01/13/avatar-and-the-riddle-of-the-space-dinosaurs/#comments Wed, 13 Jan 2010 16:44:53 +0000 Asher Elbein http://thefastertimes.com/dinosaurs/?p=220

A very pterosaur like Banshee by Wayne Barlowe

With James Cameron’s newest opus clearing huge amounts of money at home and overseas, many people are being introduced to the lush jungle moon of Pandora. Chief amongst that celestial body’s fauna are the Banshees and the Leonopteryx, huge pterosaur-like flyers of the skies. In several scenes the creatures swoop and climb and tear each other to bits in a manner reminiscent of old movies with prehistoric life. As it happens, the resemblance is not unintentional. Wayne Barlow, one of the creature designers, pretty much said as much in an interview with Io9.

…yes, being a huge paleontology buff did make me think of the vast variety of relatively little-known pterosaurs and plesiosaurs with their many, unique aerodynamic and hydrodynamic solutions.

And he’s not the first to take cues from prehistory in his alien creature designs. Not by a long shot.

Ray Harryhausen's Ymir

Possibly the first “xenodinosaur” (a term Allen Debus came up with and I am stealing for this article) to lurch across cinema screens is the Ray Harryhausen creature known as the Ymir. A creature from Venus, it was essentially a theropod dinosaur with a forked tail and a mustache. It went on an accidental rampage through Italy and was subsequently dispatched by the surprisingly effective Italian army. Pity it took the Coliseum with it.

It was followed by innumerable films where “real” dinosaurs were found alive and well on a distant planet. More often then not, any alien features these Xenodinosaurs possessed were distortions made out of ignorance by the producers. Lizards adorned with fake fins were popular in early films, especially the god awful King Dinosaur, where the titular beast was an annoyed iguana uncomfortably propped on its hind legs. Others, (Tom Corbett and Flash Gordon) produced chimerical abominations of herbivorous and carnivorous dinosaurs. Even dinosaurs that were basically accurate became alien beasts in the race to churn out low budget sci-fi, often through the magic of stock footage. Then franchises got in the act, contributing odds and ends that clearly evoke, if not dinosaurs, then prehistory in general. Creatures such as the Ronto, Tauntaun, and Bogwing of Star Wars, The Silurians of Doctor Who, and innumerable Kaiju from the Godzilla films all are inspired by prehistory.

Worse the it looks.

Alien dinosaurs show up even earlier in the pages of numerous pulps and old science fiction stories. Most of them are centered on Venus, as for a long time the constant cloud cover on that most inhospitable was considered evidence of vast rainforests. Since rainforests meant jungles, and jungles meant dinosaurs, soon the planet was crawling with prehistoric creatures. Anne McCaffrey wrote a trilogy of books called, appropriately enough, Dinosaur Planet. Edgar Rice Burroughs feature dinosaurian creatures in several of his worlds, including his John Carter saga.

There are few general connections to be made here. First, alien dinosaurs tend to appear on two types of world: the steaming jungle/swamp or the desert. There’s a fairly simple reason for this. Jungles equal old for most people, and movie producers, believe it or not, are people. Secondly, the stark landscape of a desert looks alien to us in a way even the best of jungle planets do not. Plus deserts are all over California and as such are mighty convenient places to shoot a film.

Loathing. Un-adulterate-ed loathing.

Secondly, the age of planet becomes the explanation for prehistoric life. Movie makers are taken in by the old canard that the evolution of life progresses through distinct stages. Thus, they reason, a young planet must have “primeval” fauna. As such, it must be civilized. “We’ve done it…brought civilization to Planet Nova,” a typically bone headed character from King Dinosaur says in the wake of an atomic blast that has fried the unfortunate iguana. (I cannot tell you how much I hate that film.) In a somewhat better example, Planet of the Dinosaurs allows its shipwrecked astronauts to civilize the plateau they live on by, again, dispatching the Tyrannosaur that lives there.

Finally, dinosaurs strike a chord in us. Things that look prehistoric just seem more impressive to most people, even if they can’t quite say why. A flying reptile should look like a pterosaur, or failing that, a dragon.  A big bipedal predator is going to look like a theropod. It’s not a matter of unoriginality, although alien creatures almost certainly will look nothing like dinosaurs. But it’s what the audience expects, deep down. Dinosaurs are alien to us in the most fundamental of ways, even when they seem familiar.

A good creature designer like Wayne Barlow or Nemo Ramjet knows that. They take cues from prehistory to build a better, more memorable monster. They often fail. Sometimes, as in Avatar, they succeed brilliantly.

2009 was the year of the tyrannosaur. With three new tyrannosaurids described (among them the infamous Raptorex) we gained an excellent look at Tyrannosaur evolution. With it came discoveries about Tyrannosaurus rex itself. T.rex, we now know, was an even nastier creature then previously thought. Its mouth was infested with infectious bacteria that persist in modern birds. Young tyrannosaurs regularly bit each other in the face, and may well have cannibalized each other. One myth got thrown out the window, though; Tyrannosaurs did not chew bones as was previously thought.

Clockwise from Left: Hesperonychus, Anchiornis, Tianyuraptor

Other carnivores also got their time to shine; a bevy of protobirds were announced, most of them quite small indeed. Among them was the tiny Hesperonychus, the smallest American meat eater known. It was joined by Tianyuraptor, a small chinese predator, and the primitive four winged Anchiornis.

Other meat eaters were of a greater magnitude. The massive ostrich dinosaur Beishanlong was easily 1400 pounds and likely got a good deal larger. A second species of the sloth-like Nothronychus was announced. The primitive Tawa rewrote the early history of dinosaurs. Taken all around, it was an excellent year for theropod dinosaurs.

Clockwise from left: Nothronychus, Limusaurus, Tawa

Limusaurus deserves a special mention. A bizarrely shaped herbivore, it was a member of a family that was happily carnivorous. Known from two well preserved skeleton, it was toothless, had tiny hands, and big eyes.

Duckbilled dinosaurs, or Hadrosaurs, had a good year. Since Hadrosaurs are by far the most common group of dinosaurs, the wealth of bone and fossilized soft tissue make them very useful subjects of study. The announcement of a new dinosaur mummy (a Brachylophosaurus nicknamed Dakota) and some excellent studies of preserved skin and blood vessels yielded great insights into the soft tissues of dinosaurs. A dwarf hadrosaur from Italy made the rounds. A study of Hadrosaur locomotion posited that the most efficient method of movement for a duckbill was hopping, although it is unlikely that they did so.

Tianyulong made waves when it was announced, for the simple reason that it was an heterodontosaur (a very primitive herbivorous dinosaur) with feathers. This is the first conclusive proof that feathers may have been common in all dinosaurs, not just theropods. Another primitive herbivore, Aardonyx, was announced late in the year. It was a late surviving prosauropod, an evolutionary grand uncle to the massive long necked dinosaurs. An even earlier creature, Panphagia, provides a look at what the very earliest sauropods looked like.

Clockwise from top left: Panphagia, Tianyulong, Aardonyx

One place where 2009 was not auspicious was in the portrayal of dinosaurs in cinema and television.  Land of the Lost gave us a freeze dried Allosaurus and a Tyrannosaur with an admittedly rather funny grudge against Will Ferrell. The movie wasn’t a huge hit with either audiences or critics, in part because of an oddly dirty tone and in part because, well, Will Ferrell. Ice Age 3: Dawn of the Dinosaurs aired rather better commercially, but lost points because of the ugly designs on the dinosaurs. The ITV television show Primeval (a drama about prehistoric creatures, soap melodrama, and conspiracies)  wrapped up with a decent third season, was canceled, and has now been uncanceled. The miserably bad “documentary” Clash of the Dinosaurs aired, whipping up a firestorm in the blogosphere with its rampant quote mining. To balance the scales, we got Ponyo, a dreamy animated film crawling with prehistoric sea life.

Listing the entire spectrum of discoveries and theories would take a good while, so we’ll end it here. Here’s looking toward 2010!

Every news outlet in the world knows it. Photographs, cartoons, sketches, whatever–all have been and continue to be used to illustrate articles. Get the right image, and the story writes itself. And more often then not, the story that gets written has more to do with the image then the facts of the case. Ask any Pulitzer Prize winning photographer; the pictures that win are the ones that confirm, in some way, an essential story we tell ourselves. People remember the photos and illustrations that accompany an argument far better then the argument itself. If you can show it, then to some extent you have proved it.

There’s a logical term for this: it’s called  ”Proof by Illustration”. Keep it in mind; we’re going to come back to it.

Tawa by Jorge Gonzalez

Let us now turn our attention to Tawa hallae, an interesting little theropod from the late Triassic. It’s notable for a few reasons:  among them are it’s bones, which are filled with air, a interesting but rather technical cladistic placement, and what it tells us about the dinosaur population of the Triassic era Petrified Forest. It’s also notable for being known from two nearly complete specimans and assorted scraps, which is rare for small Triassic theropods: for the most part, the bones are crushed and mangled by time and pressure. It was discovered a few years back, but due to the painstaking work involved in describing an animal scientifically, the paper has only just come out in science. And it is accompanied with some beautiful art by Jorge Gonzalez.

A Portrait (also by Jorge Gonzalez)

Nice, isn’t it? Mr. Gonzalez has picked out the scars on the snout, given it a slightly calculating expression reminiscent of a hawk. You can easily imagine the little fellow scuttling around the forest snapping up lizards, or stopping to preen its feathers.

However, there is a slight problem. Tawa isn’t known to have had feathers. None of its close relatives are known for it either. There’s no evidence for it. The images, gorgeous as they may be, are basically speculation.

There’s nothing wrong with speculation. It is, in fact, a huge basis of Paleontology. I don’t fault Mr. Gonzalez for dressing his beast in feathers, any more then I’d fault him for illustrating the probable appearance of an animal known from only a few bones. It’s what a good paleoartist does. And in all fairness, the word “feather” never once appears in the scientific paper. No one is claiming Tawa was fluffy.

Oh. Wait. Never Mind.

This is a rather nice example of the “Proof of Illustration.”  There’s no evidence for a feathered Tawa, either for or against. The fossil isn’t preserved with feathers. The paper never mentioned them.  But the illustration is there, and the majority of people will look at the image and assume the animal had feathers.

I find this interesting. In truth, the main reason most dinosaur myths hang on so long was because they are just too iconic to go away. Swamp dwelling brontosaurs, lurching tyrannosaurs, sluggish stegosaurs, gliding pterosaurs.  Those images, stamped into the public mind by Charles R. Knight and Zednek Burian, linger. Toys get made out of them, they are adapted for the silver screen, or swiped by inferior artists. They proliferate and achieve a kind of legitimacy. We’re so used to them we can’t imagine anything else.

The Dinosaur Renaissance had led us to many things, and one of its implicit promises was that all of the old and wrong images–iconic as they were–would be safely confined to the art galleries and history books. But the “Proof by Illustration” abides; it is a fundamental part of how people think. We may have gotten rid of some of those older ideas, but we’ve already begun shaping new icons, often with just as little evidence to support them.

Science marches on. Illustration, like imagination, often bounds far ahead–or lags far behind.

Tyrannosaurus vs. Ankylosaurus in Clash of the Dinosaurs

Fantastic enough, in fact, to be the operating premise of two recent cable shows.

Last night, starting at 8:00 pm, Discovery aired the first two episodes of its new miniseries Clash of the Dinosaurs. The two episodes aired, “Extreme Survivors” and “Perfect Predators,” nominally deals with the adaptations of young dinosaurs and predatory dinosaurs. Prior to that, History Channel scooped them with its own Jurassic Fight Club, which analyzed the bloody battles between specific types of dinosaurs. That show took a more narrow approach, but still managed to fit in plenty of dinosaurian gore.

The two shows have very obvious similarities. Both claim to examine the biomechanics of dinosaurs; both interview scientists in a “talking head” fashion so familiar to documentary viewers. And both offer up copious amounts of dinosaur mayhem. Jurassic Fight Club began with a bloody battle between two Majungatholus, and moved on to bigger and better beat downs from there. Clash of the Dinosaurs also served up the carnage, with two fights in its opening  episode. A Tyrannosaurus makes a lunge at a Triceratops and gets stabbed in the eye. A duo of Deinonychus slaughter a sauropod in a wash of blood.

Heady stuff, clearly. A cynical person would observe that the point of the show is to show dinosaurs duking it out, not to inform or educate. And they would have quite a bit of evidence to back up the assertion. In both shows, the proportion of evidence to evisceration is badly skewed. What little science is present is hidden in a welter of didactic pronouncements, half truths, and speculation. “Tyrannosaurus Rex was a caring parent,” we are told. How do we know? “Quetzalcoatlus had excellent vision and could detect the UV traces of urine trails from miles up.” Awesome. Can you prove it?  Jurassic Fight Club is equally bad. “Majungatholus represented an inbred population, which led to strange growths on its head.” That’s cool. Where’d you get it from?

Tyrannosaurus Challenges Nanotyrannus in Jurassic Fight Club

The scientists, of course. But even here there’s an issue; whatever was said in the interviews, we only get to hear the bits displayed on the program. And those bits only ever tell us how awesome the animals on display are. When discussing the Deinonychus, we hear that they were some of the nastiest dinosaurs around. But we never hear why. It’s presented as a self evident fact by the producers, and any intelligent discussion or answers that were present in the interviews are cut down to sound bytes.

What’s worse is the blatant padding in both shows. It’s clear that only a certain amount of scenes were animated for either program, and instead of saving them up and making them count, they are repeated endlessly. We see them from different angles. Tinted. Flipped. Split second snap shots. Every bit of juice available is squeezed out of them. I understand and sympathize with the expense of animating a welter of different shots. I have no issue with an occasional repeat. But the sheer, grinding repetitiveness is appalling.  By the time we get down to the big fights in Jurassic Fight Club, we’ve seen them several times over. Clash of the Dinosaurs is worse, with later segments made up entirely of recycled footage…now rendered excitingly new by a different arrangement and narration. What should be spectacular becomes first familiar, then banal, then ultimately boring.

So? You may be asking. Aren’t these two shows just lame cash grabbing attempts? Why should we care if they refuse to cite sources or pay anything more then lip service to science? What do we care if they’re boring?

The thing is, I don’t think that they’re meant to be lame cash grabs. While there’s a definate element of sensationalism, there is also a desire to educate. Both shows want to teach us about dinosaurs by sneaking in facts under the gory effects. Kudos to them for trying it. But when shows like these two prsent speculation as fact, there is a problem. Admittedly, I don’t want a show that’s all facts and figures. But I would like some kind of acknowlegment of what is speculation. The simple addition of “Maybe” or “Perhaps” yields not only a more accurate show, but leaves room for us to think for ourselves. Maybe T.rex did care for its young…but then again, maybe it didn’t. If you don’t know much about dinosaurs, and you can’t pick out the innacuracies and unsupported claims, “Maybe” and “Perhaps” are your friends. They beckon you in, tease you with posibilities, prod you to investigate further. But these shows allow no room for speculation on the part of the audience. Only the producers are permitted that luxury. Instead, we are told how dinosaurs were. Why bother to learn more? The scientists have the gospel, these shows tell us. They can peer back into the mists of time and deliver truths from their ivory tower. The dust and hardwork? They don’t matter. The exhausting study in a tiny stooroom? No one cares. We know it all. And we don’t need to tell you how we know it. We just do.

I’m sure that’s not the concious thought. Or even the unconcious one. but it is one implication, and to me it’s a worrying one. But both shows deserve kudos for recognizing that most of us just want to see dinosaurs rip each other to pieces. They give us what we want.

But hey. It’s fun watching those dinosaurs.

While this is a bit unexpected, it’s not by any means new. Crocodiles and Alligators are becoming increasingly known for surprisingly complicated social behaviors. Their nesting behavior is already remarkably similar to birds; the female broods her eggs and guards the nest and young.

So what does this have to do with dinosaurs? Well, Crocodylians are an ancient group. They aren’t descended from dinosaurs; they’re more along the lines of evolutionary grand uncles. They are once piece of a puzzle. To see fill in the rest of it, we need to clamber up the cladistic tree, past dinosaurs, and onto the spreading branches of the great family known as birds. Here we have a remarkable assortment of social and sexual behaviors. Geese that mate for life, harems kept by chickens, promiscous hummingbirds, the forlorn and akward Kakapo (who mates rarely and, it would see, more by accident then anything else), monastic hornbills and finally, the clever Corvids–Crows, Rooks, and the Ravens.

If Crocodylians provide a glimpse at how dinosaurian ancestors paired up and nested, then birds like Ravens and Hornbills give us an interesting look at how dinosaurian behaviors may have advanced in the intervening 65 million years. Ravens are an excellent example. As shown in The Mind of the Raven, Bernd Heinrich’s excellent and entertaining study of Raven social behavior, Ravens mate for life. Crows do as well. And not only that, they raise successive young and are often quite affectionate with each other, spending a great deal of time grooming, caressing, playing, and mumbling with their mates. They apparently show little interest in adultery. Moreover, their interaction with young is an interesting one; while Ravens take care of their chicks and teach them a great deal, they eventually drive them off. Crow Troops, on the other hand, often have large extended families, with breeding pairs helped by succesive generations of offspring.

So. What does this tell us about dinosaurs? Not much–and quite a bit. For one thing, it’s basically impossible to say how dinosaurs behaved during mating (or at least do so with a straight face.) The family we call Dinosauria encompassed a diverstiy of form and behavior that was–and is– truly staggering.  Even within the relatively small group of dinosaurs alive today, the birds, there are hundreds of different social and sexual behaviors. To try and extrapolate the sex lives of sauropod dinosaurs from a hummingbird would be a truly spectacular act of insanity. Form dictates function after all, and the manner in which beasts like Stegosaurus and Triceratopsmated was as much a product of their anatomy and environment as their linneage. (Imagining the difficulty presented by the sharp plated back of a Stegosaurus would give any man pause for thought. Turtles have figured out a rather simple, if long, solution to a similar problem, but that’s an article for another time. )

But here’s the thing; Dinosaurs share several traits with both their crocodylian uncles and their feathery descendents. They nested; we know this because we’ve found the eggs and the nests of almost every branch of their family. They brooded; we know this because we’ve found fossils of that, too. They share a comman ancestry with crocodiles and some of them apparently fed their young after birth. While we can’t say much more then that for Dinosaurs as a whole, we can use what we know about birds to tell us a good deal about the dinosaurs that were most like them: the theropod dinosaurs like T.Rex and Velociraptor. If most birds looked after their young, and most crocodiles gaurded their nests, then theropods likely did things in a fairly similar fashion.

So did Velociraptor mess around? Did Allosaurus live with its inlaws? Did Tyrannosaurs mate for life, or casually hook up? We’ll never know. Sex rarely fossilizes, and despite one graduate student’s quip that he’d “love to find a six footed trackway,” the exact nature of any given dinosaur’s mating behavior is sadly lost the midsts of time.  But by examining the sexual relationships of their relatives–romantic ravens and adulterous alligators, among many, many others–we can gain a precious glimpse of the love lives of Dinosaurs.

Right?

Well, as it happens, not so much. As humanity spread across the globe, they found plenty of things terrifying enough to brand themselves into cultural nightmares. In honor of Halloween, we’re counting down the five most horrifying creatures that mankind met in its march across the world. Creatures like…

5: The Mega Shark

Humanity has always been afraid of the ocean. Legend after legend has told of cruel monsters waiting just outside the breakers, ready to tear and devour any who are foolish enough to brave the waters. I’m not saying that Carcharodon megalodon caused it. But it damn well helped.

A denizen of warm waters, much like its relatives the Great White and the Mako, Megalodon was a truly epic beast: a 60 foot long shark, able to devour just about anything that crossed its path. Whales of all sizes, dolphins, sea turtles, and dugongs all were on the menu. And it’s not entirely impossible that the menu included humans. Megalodon’s known range is quite large, though it had shrunk some what by the time Homo Sapiens arrived. Still, the warm waters of the Indian and Pacific likely provided a last haven to these massive beasts, and humans have been tooling around those shores for quite a while. It was not a long interaction, as the Megalodon  was already on its way out when humans appeared. Still, the creature has left some mark on human conscious: Megalodon is nearly as famous as T.rex in popular culture.

4: The Scimitar Cat

Ice Age Europe was a cruel place. Freezing cold and half covered in glaciers, it provided a special challenge to humans. Unlike other continents, it did not host extravagant monsters, making due with the usual ice age suspects: mammoth, cave bear, wooly rhino, dire wolf. All of them terrifying, given the right circumstances. But the scimitar cat, Homotherium, was in a league of its own.

With a hyena like form and teeth adapted for slashing rather then stabbing (the major disadvantage Saber Tooth Cats faced was long, fragile teeth) Homotherium was just the right size to take down a human being. Long front legs and a cheetah like nose and eyes made it a truly formidable predator, able to move fast, take in air efficiently and see very, very well. Moreover, it was perfectly placed to scare the bejesus out of people: Homotherium finally went extinct sometime around 9,000 B.C.E. For those of you that are up on your history, that’s right at the crux of the Neolithic, when most of the mega fauna in Europe and America were long extinct. But in the dark forests and caves of Europe, the scimitar cat lurked as one last, deadly reminder of the ice age.

3: Haast’s Eagle

The Maori people arrived on the shores of New Zealand to find a world populated by birds like the Moa, all of them docile and unready for the scourge of human hunting. All except one. With a shrill scream and a gust of air, horrible death fell from above at 30 pounds and 50 miles an hour. Harpagornis, the Haast’s eagle, welcomed the Maori to New Zealand.

With a wingspan of 10 feet, Haast’s Eagle was the largest of the true raptors, outstripping even the largest vultures. While Golden Eagles approach that wing size, they are 40 % smaller. And Golden Eagles have killed people. With relatively short wings and a long tail, Haast’s eagle was fast and maneuverable in the scrub forests, preying on the giant moa and other flightless birds. Being struck by one was the equivalent of receiving a clawed cinder block to the head from 82 feet up. And as Moa began to be hunted to extinction, humanity was almost certainly next on the menu. But Haast’s eagle was never common, and when the Maori finally grew tired of having clawed cinderblocks dropped on their head, they drove it to extinction in 1400 C.E.

2: The Short Faced Bear

In North America humanity was spreading with, if not speed, then at least some alacrity. The mega fauna were dying off, thanks in part to hunting, and the forests were beginning to look a bit safer. But if you’ve made it this far, you can probably guess this was not the case. Neither eagles or sabertooths awaited the newly arrived native Americans. Instead, it was bears; grizzlies and black bears and polar bears. Any one of these animals was more then capable of killing a man in an extraordinarily messy fashion; but the Short Faced Bear raised it to a high art.

Five feet tall at the shoulder, 11 feet when standing upright, the Short Faced Bear was well adapted for death dealing. Massive jaws, long canines, and a bulk of up to 1,800 pounds were combined with long limbs to make it the most powerful land predator in America. Given that modern bears show no special running adaptations and still can barrel along at speeds faster then a man can run, the Short Faced Bear was probably extremely fast, possibly able to reach speeds of 40 miles per hour. That, combined with the natural toughness of bears, likely made it a prime killer of mastodon… and humans as well.

1: The Dust Dragon

Australia. The continent already holds its fair share of bowel churningly terrifying creatures. But when the Aborigines landed on Australia’s shores, they found a land populated with creatures stranger then anything anywhere else in the world. Marsupial lions, giant wombats, and short faced kangaroos roamed the grasslands. Ok, they thought, we can handle this. Then they met Megalania.

Imagine a Komodo dragon nearly 26 feet long and up to 4,300 pounds, it’s jaws loaded with ripping teeth and septic venom. While rare, it was able to sustain high levels of activity for a longer amount of time. That combined with it’s size and probable love of ambush attacks, made it a creature to be feared. To put it in context; a seven foot Komodo monitor is more then capable of taking down a human. A 26 foot predator is capable of taking down a lot of them. And Komodo monitors are tough, able to take wounds most animals would die from. Scale that up, and you have juggernaut predator, the apex monster of the dream time. Megalania likely went extinct 39,000 years ago, leaving plenty of time to sear itself into Aboriginal mythology.

We’re luckier then we know to live in a time without megafauna. But we can still remember, on dark nights, the terror that our ancestors must have felt when they made their way through a world full of monsters.

Tyrannosaurs have been somewhat in the news lately. A recent study announced that Sue the T.rex died from a debilitating infection common in modern birds, Sampson was put up for auction (he didn’t sell) and the unfortunately named Raptorex was introduced to the world. Now, from the closing days of the mighty Society of Vertebrate Paleontology meeting comes news of another unusual little tyrannosaur.

One with horns.

Alioramus Altai: The newest addition to the Tyrannosaur Family

Alioramus Altai, a nimble 20 footer from the latest cretaceous sediments of Mongolia, is half the size of its contemporary Tarbosaurus. While easily large enough to dispatch modern predators, Alioramus possessed a body plan quite different from the rest of its stocky kin. Where its larger relatives crushed bone and snapped muscle in a bite, Alioramus likely probed at carcasses or snapped up smaller prey. With lengthy legs and snout, slender jaws, and a narrow body, Alioramus was a jackal compared to the bearish Tyrannosaurs. But it’s the horns that will draw attention–eight small horns spaced along the skull. While rather puny looking, the specimen found was young and the horns might well have been far more impressive in adults. The horns were likely useful for display purposes or interspecies interaction, with adults signaling like modern birds.

Now, Alioramus itself is not particularly new. You can see a rather fine robotic one at Animal Kingdom’s Dinosaur ride. But this is a new species, not a new genus. The previous Alioramus species, A.remotus, was discovered in the 70’s by the Russian scientist Sergei Kurzanov. But that beast was known from scrappy remains and an incomplete skull. So while it was suspected that Alioramus had horns, no one really knew for sure.

Aliroramus Altai is known from excellent remains: a nearly complete skull, neck, back bone and legs. We now know with real certainty what this previously mysterious animal looked like. And the find shows something interesting in an ecological sense: Tyrannosaurs had spread and diversified to the point where there were several distinct types, often living in the same ecosystem.

To wit, Alioramus was a creature that was able to exploit an entirely different prey source then a huge Tyrannosaurus or the swift Albertosaurus. In its turn, Alioramus couldn’t exploit the ecological role of really little tyrannosaurs like Raptorex (which lived far earlier, but I’m confident equally small Tyrannosaurs will be found from the late Cretaceous. You heard it here first, folks.)

This find also explains something that has long troubled Paleoecologists: the real lack of diverse predatory dinosaurs around the end of the Cretaceous. For the longest time it appeared that the sum total of large predators in Asia and America were all variations on the tyrannosaur model, and that’s an extraordinarily unhealthy ecosystem. Raptors and troodonts were rare in America/Asia during the latest Cretaceous as well, and it wasn’t really clear why. Now, with the discoveries of smaller Alioramus, we get a look at an ecosystem that’s far more complex then we thought–Tyrannosaurs squeezing out not just other large predators, but smaller predators as well.

Alioramus might even have competed with the young of Tarbosaurus, who were built in a similarly slim way.

So, to sum up: a small, nearly complete horned tyrannosaur from Asia tells us a lot about Tyrannosaurian diversity. The most archetypal family in all of the Dinosauria, it seems, still has many surprises left in store.

Anchiornis: The Critter in Question

extravagantly fluffy tail. As the newest announcement at the annual Society of Vertabrate Paleontology meeting  this little dinosaur is kicking up quite a stir.

Why? It all has to do with three things; its age, its linneage, and wether or not it could fly.

First, its age. Anchiornis is from the middle Jurassic, the second great epoch in the age of the dinosaurs and the one in which feathered theropods (meat eating dinosaurs) are positively known to have emerged. There’s another famous feathered dinosaur from the middle Jurassic; Archeopteryx, the famous “first bird.”

Here’s the thing though. Archeopteryx came later then our new friend Anchiornis. And that’s interesting for a lot of reasons; among them the new, sneaking suspicion that “the first bird” may not, in fact, be the first.

But here the evidence makes things a bit more twisted. Archeopteryx is what is known as an “avialian”–a protobird. In the tangled game of theropod taxonomy, its rather unclear where exacly avialians lie in relation to other families. So when Anchiornis was intitially reported as an avialian, the lamentations of taxonomists were loud and prolonged. “How the hell do we fit this thing in with Archeopteryx?” They cried in despair. But when a new and better skeleton was found, something else came to light. Anchiornis was not an avialian. It was a troodont.

To put this in context, troodonts are primarily Cretaceous animals; they are a sister family of the famed dromeaosaurs, or raptors. Both families are rare

The Bird Family Tree: Anchornis fits uneasily at the juncture between dromeosaurs and troodonts. And this is the simplified version. You can see why Taxonomists tend to get headaches.

in the Jurassic, and when they do show up it’s only in the latest portions of the epoch. But here we have a recognizable troodont, extravagantly feathered, quite a few millenia earlier then it should be. It clouds an important issue of whom is related to whom. The Middle Jurassic was the time when the dromeaosaurs (primitive beasts such as Microraptor), the troodonts (Anchiornis), and the avialians (Archeopteryx) were all splitting off from each other, and now the genealogical waters have been muddied.

Taking all of this into account, the next question is obvious; could Anchiornis fly? Did it beat Archeopteryx and other avialians into the air? Unfortunately, no. There are a few reasons why, and they primarily lie with wings structure. While all troodonts, dromeosaurs and avialians appear to have been feathered and equipped with the “leg wings” that make Microraptor and Anchiornis so distinctive looking, that doesn’t mean they were doing anything in particular with them. Anchiornis had wings, but the

Two methods of early flight: Microraptor glides like a Biplane, while the Hawk demonstrates powered flight as Archeopteryx may have used it.

feathers were arranged symetrically, which provides little to no lift. It had none of the gliding specializations of Microraptor, and lacked the adaptations for powered flight exemplified by Archeopteryx. It actually appears that the troodonts weren’t beating anyone; they were in fact some of the last off the ground, if they ever made it at all.

So there we have it; a confusing little beast, muddying up an important taxanomic issue in the study of bird origins. For now, at least, Archeopteryx can rest easy on its perch as the first powered flier. The discovery of Anchiornis simply helps fill in the tree underneath it.

Stay tuned: The Annual SVP meeting is going on, and some cool announcements should be coming out of it. I’ll blog about them as they come.