Zombie Birds, Astronaut Fish, and Other Weird Animals

by Becky Crew

  PART THREE

  ANCIENT CREATURES

  The Largest Feathered Animal Ever

  YUTYRANNUS HUALI

  “So I don’t look ‘fierce’ with all these feathers. Who cares? I’m fabulous!”

  TYRANNOSAURUS REX HAD A gigantic feathered cousin, according to newly discovered fossil evidence, which proves that feathered dinosaurs were bigger than we could have ever imagined.

  The Tyrannosauroidea was one of the longest-living subgroups of theropods, which were bipedal (walking on two rear legs), mostly carnivorous dinosaurs. According to the fossil record, their existence spanned from the Middle Jurassic, which lasted from 176 to 161 million years ago, to the Late Cretaceous, around 65 million years ago. At this stage, they had achieved apex predator status across the Northern Hemisphere and some species were seriously outgrowing their ancestors, reaching over 2200 pounds in weight and up to 33 feet in length.

  In mid-2012, the discovery of one such dinosaur was reported by a team of scientists led by paleontologist Xing Xu from the Chinese Academy of Sciences in Beijing, who has discovered some thirty new species of dinosaurs so far. They unearthed the new tyrannosauroid from the Lower Cretaceous level of the Yixian Formation, which is an extremely fossil-rich formation in Jinzhou, Liaoning, in the northeast of China, which spans about five million years within the early Cretaceous period. The Yixian Formation has produced a wealth of surprisingly well-preserved fossils of everything from feathered dinosaurs and the most ancient bird species to fish, spiders, flowering plants, pterosaurs, and mammals. But this new dinosaur was particularly special.

  Named Yutyrannus huali, which means “beautiful feathered tyrant” in a combination of Latin and Mandarin, the dinosaur was pieced together from three 125-million-year-old near-complete skeletons, namely one adult and two juveniles found alongside fossilized pieces of sauropod—the remnants of a hunt, perhaps. The researchers, publishing in Nature, described Y. huali as having weighed a hefty 3098 pounds and stretched 30 feet long, with relatively long forearms for a tyrannosauroid. But most incredibly, each specimen showed signs of having been coated in a down of 6-inch-long filamentous feathers which, rather than being like the flat, rigid feathers of a modern crow or seagull, would have been similar to the thick plumage sported by modern emus and cassowaries. This makes Y. huali the largest feathered animal ever known, around 35–40 times the size of the previous record holder, Beipaiosaurus, a Chinese dinosaur with a disproportionately compact head, a stout, stocky body, humungous claws exploding from its forearms, and clumps of feathers around its neck, rump, and tail. “The discovery of Y. huali provides solid evidence for the existence of gigantic feathered dinosaurs and, more significantly, of a gigantic species with an extensive feathery covering,” the researchers concluded.

  Due to the apparent structure of Y. huali’s feathers, Xu and his team have suggested that their function was less to do with flight and more to do with insulation, as it is with today’s flightless birds sporting similar filamentous fuzz. But exactly why this occurred is pretty puzzling, seeing as very large animals, such as elephants and rhinoceroses, retain heat very easily and find it difficult to keep their body temperatures down. This is why they need thick hides instead of dense fur coats. The researchers considered what the environmental conditions would have been for Y. huali and noted that this area in China would have been considerably cooler 125 million years ago, suggesting that, like the woolly mammoth and the American bison, it lived in a cold enough environment to warrant a fuzzy winter coat, in spite of its large size. “[The] presence of long feathers in the gigantic Y. huali could represent an adaptation to an unusually cold environment,” they wrote. “Y. huali lived during a period that has been interpreted as considerably colder than the rest of the Cretaceous (a mean annual air temperature of about 10 degrees Celsius (50°F) in western Liaoning, in contrast with about 18 degrees Celsius (64°F) at a similar latitude in the Late Cretaceous).” This is of course speculation, and because the plumage had only been partly preserved on each of the three specimens, the researchers were careful to point out the possibility that, like Beipaiosaurus, Y. huali’s plumage was restricted to certain parts of its body. In this case there’s a chance their feathers performed more of a display function than a warming one.

  Of course, it’s time to discuss the elephant in the room, which is the question of whether this discovery can tell us any more about whether or not T. rex was similarly fuzzy. While we don’t have any direct evidence of it yet, and T. rex did live in a climate that was much warmer than Y. huali’s stomping ground, the possibility can’t be ruled out. “Yutyrannus dramatically increases the size range of dinosaurs for which we have definite evidence of feathers,” says Xu. “It’s possible that feathers were much more widespread, at least among the meat-eating dinosaurs, than most scientists would have guessed even a few years ago.”

  A Venomous Dinosaur?

  SINORNITHOSAURUS

  IN 2009, A CONTROVERSIAL paper suggested that a group of small, birdlike therapods might have been venomous. The study, published in Proceedings of the National Academy of Sciences and led by paleontologist Enpu Gong from the Chinese Academy of Sciences, centered on an unusual half-inch-long tooth from the top front row of the mouth of a Sinornithosaurus—a genus of feathered dinosaur that lived more than 120 million years ago. Not only did the researchers find this tooth to be very long and fanglike, but they found a thin, distinct groove running right through it from root to tip, which Gong suggested could have functioned as a channel for venom to pass from the animal’s skull into the flesh of its prey. A hollow pocket in the side of the Sinornithosaurus’ face, evidenced by the shape of its fossilized skull, was identified as a possible venom gland, and a pitted canal running between it and the base of the teeth could have acted as a venom-collecting duct.

  Modern venomous snake species can be separated into two groups, front fanged and rear fanged. Front-fanged snakes are the most common group—all Australian venomous snake species, including the red-bellied black snake, are front fanged—their hollow, syringelike teeth are designed to inject a very potent venom into the flesh of prey. Rear-fanged snakes such as the vine snake are far rarer, their fangs sitting further back in their mouths on the upper jaw. Running along the back of each tooth is a groove through which a mild form of venom drips, its purpose related to digestion rather than defense or killing.

  Citing the teeth of rear-fanged snakes as morphologically similar to the unusually long Sinornithosaurus maxillary teeth, Gong suggested that this predatory raptor would have hunted mainly small birds and mammals, using its fangs to “grab and hold” its prey, penetrate the layer of feathers or fur and deliver a 0.2-inch-deep bite. Like rear-fanged snakes, the dinosaur might have had to chew on its prey to dispense enough venom into its body to induce a shock response. “The poison of Sinornithosaurus may have been similar in properties to rear-fanged snakes and helodermid (bearded) lizards in that it did not kill the envenomated animal quickly but rather placed it into a rapid state of shock,” he said.

  But Gong’s claim is not without its critics. Tom Holtz, a paleontologist who specializes in carnivorous dinosaurs at the University of Maryland, responded by saying the unusual length of the fangs could have been caused by regular-sized teeth slipping out of their sockets after the animal had died. He also suggested that the grooves could simply be the depressions found in most theropod teeth, only more pronounced in this particular specimen due to wear and tear. For many years, paleontologists have believed that the function of these depressions relates to how bayonet blades function, the groove helping to relieve surface tension once the tooth has penetrated a surface, which ensures a less painful extraction. Holtz added that many dinosaurs have a small cavity in their jawbones, but these have typically been interpreted as air sacs required for cooling, not pockets for venom glands.

  In 2010, a group of paleontologists from Argentina released a paper in Paläontologische Zeitschrift agreeing with Holtz’s crit
icism of Gong’s venom theory: “We fail to recognize unambiguous evidence supporting the presence of a venom delivery system in Sinornithosaurus.”

  Gong and his team responded by publishing a paper in the same issue of the journal, arguing that recent research led by venom expert Bryan Fry from the Australian Venom Research Unit has indicated that venom glands in lepidosaurs (a subclass of scaled lizards which includes the common iguana) are far more common than thought, so it would be a mistake to assume that archosaurs (a group including extinct non-avian dinosaurs, crocodilians, pterosaurs and modern birds) with grooved teeth had no venomous taxon, or group, in their ancestry, and were not venomous themselves. It’s an issue that remains unsolved, but no dinosaur has so far ever been conclusively proven as having been venomous. This means the onus is on Gong and his team to come back with some unambiguous proof for their claim.

  Arguments aside, Sinornithosaurus, say you did actually have this venomous bite. I’d imagine it’d be the kind of thing you could easily get carried away with, like an out-of-control James Bond. Say, for example, you’re playing Sonic Racing at Dromaeosaurus laevifrons’s house all, like, “Hey, remember when games didn’t go so fucking fast that you could actually see where you’re going? Christ, we’re old,” when D. laevifrons will tell you, “I’m going to make a sandwich. If you cheat when I’m gone I’ll know.”

  “But it’s almost midnight …”

  “Just because you can’t have carbs before bedtime …”

  “Dick.”

  So you’ll unpause and move your Shadow forward a bit because he just implied that you’re fat, but you’ll underestimate just how anal D. laevifrons is and the moment he gets back, he’ll be like, “Oh my god, you totally cheated.”

  “No I didn’t.”

  “Yeah, right. Hey, what are you doing … Hey! Heeey!”

  “Oh. Sorry. My mistake.”

  “That was my leg. Jesus! That really hurts. Wait, you’re leaving? Right now?”

  And before he can point out that if you bring a bottle of wine to someone’s house, you’re not really supposed to take it home with you just because you drank his wine instead, he’ll go into shock, and you’ll grab the leftover quiche, too.

  But the only lesson you’ll learn from this whole experience, Sinornithosaurus, is how easy it is to get out of a shitty situation by, you know, injecting your friends with venom. Like, you’ll be at your girlfriend’s house and she’ll try on this hideous new dress she just bought and she’ll be like, “Does this make me look fat?” and it will, Sinornithosaurus, so you’ll be like, “Erm, hey look behind you!”

  “What? … Ow!”

  Your boss will ask you what the hell kind of report that was you left on his desk (no kind, Sinornithosaurus, it was terrible), so you’ll bite him and take the rest of the day off. You won’t have any cash to buy an ice cream so you’ll bite the shopkeeper. And while you might think this is all pretty great, remember, Sinornithosaurus, this kind of behavior isn’t without its consequences. Which means you’ll be at some party with your new girlfriend and somehow your ex will turn up all, “I don’t want to make a scene, but injecting me with poison was a really dick move, even for you.” And then your current girlfriend will be pissed because she didn’t even know you had an ex, let alone one you injected with poison and left for dead, and they’ll end up being best friends just to spite you. Plus your boss will almost definitely fire you when you show up for work on Monday and every shopkeeper in town will close his doors in your face, and your best friend isn’t speaking to you anymore, because he’s dead. Hardly seems worth it now, does it, Sinornithosaurus?

  What’s That on Your Face?

  TYRANNOSAURUS REX

  “I want to break up.”

  “What? Why? We’ve been getting along so great!”

  “Yeah, I know, I’m just not ready for a relationship, and I’m just … confused about things. You know?”

  “You looked in my medicine cabinet, didn’t you?”

  “No. Okay, yes. You’re disgusting.”

  “I’m not the one who ate an entire tube of Pringles by myself last night.”

  “I’m sorry, I couldn’t hear you over all the noise your face lesions are making—”

  “What lesions?”

  “—through that cheap concealer you’re trying to hide them with.”

  “Goddamn.”

  UNUSUAL LESIONS AND PUNCTURE marks found on the skulls of Tyrannosaurus rex and other tyrannosaurid species have revealed that a common avian infection might have plagued these ancient predators. And infighting appears to have been the factor that spread it.

  In a 2009 paper published in Palaios, a team of scientists from Northern Illinois University and the Burpee Museum of Natural History described the results of their examination of “Jane,” a 23-feet-long T. rex skeleton found in the Hell Creek Formation in Montana in 2011. With a slightly asymmetrical snout and four partially healed oblong lesions along the left side of her skull, it’s been suggested that Jane shows evidence of aggression amongst juvenile tyrannosaurs as they compete for dominance, territory, or resources. The team compared the positioning and orientation of the lesions along Jane’s nasal and upper jaw regions to the jaw shape of the only fossilized vertebrates found in the Hell Creek Formation that were large enough to inflict such wounds—other theropods and crocodilians. They found that the size, shape, and spacing of the fossilized juvenile theropod teeth corresponded convincingly to the positioning of Jane’s lesions, unlike those of the crocodilians.

  Evidence of face biting is not uncommon in the tyrannosaurid fossil record, but this is the first indication that this kind of behavior was not just restricted to fully matured adults. As Jane’s age has been estimated to be around twelve years—two years prior to the age of sexual maturity for the T. rex—the researchers were able to rule out the possibility that this was strictly part of courtship-related behavior. They also found indications of partial healing through bone repair, which suggests that though this face biting was not typically fatal, it could cause a slight warping of the muzzle as it remodeled itself. “Jane has what we call a boxer’s nose,” says Joe Peterson, geologist from Northern Illinois University and lead author of the study. “Her snout bends slightly to the left. It was probably broken and healed back crooked.”

  That same year, a study published in PLoS ONE led by paleontologist Ewan Wolff from the University of Wisconsin described a parasitic infection that causes severe erosion of the jawbone and ulceration of the mouth and esophagus, ultimately leading to death by starvation. Of the sixty-one tyrannosaurid specimens Wolff examined, 15 percent of them had the telltale signs of this infection—several smooth-edged pits in the lower jawbone. While these were quite distinct from the rougher-edged bite marks found in Jane’s skull, in many of the specimens examined, both kinds of lesions were present, suggesting that the infection could have been transmitted through face biting in much the same way as the face cancer now threatening to drive Tasmanian devils to extinction.

  Wolff also discovered that the lesions caused by infection were remarkably similar to those found in the beaks of modern birds such as turkeys, chickens, and pigeons that have been infected by a parasite called Trichomonas gallinae. Modern birds can pass on trichomoniasis by simply touching each other on the beak, which can lead to severe ulceration of the upper digestive system and ultimately starvation. This suggests that there could have been a shared affliction between modern birds and extinct tyrannosaurid species, which is yet further evidence of how closely the two groups are related.

  King of the Rabbits

  NURALAGUS REX

  “Your Majesty, the enemy troops are lined up at the shoreline. What would you have us do?”

  “Sit on them.”

  “Your Majesty?”

  “Sit on them. Sit. On. Them. What are you, deaf? Because the only person who should be deaf in this castle is me. Do you see how small my ears are?”

  “Begging your pardon, Your M
ajesty, but I’m not sure any of us are big enough to sit on our enemies and make a difference …”

  “I have one other strategy for situations such as these but I’m reluctant to tell it to you because if you fuck it up we’ll all be doomed.”

  “Your Majesty?”

  “I learned this tactic when I was just a boy, and my father, King Rabbit VI, had to defend his kingdom from some kind of enemy force, I can’t remember what. He said to me, ‘Son, never fuck this strategy up, because if you do, we’ll all be doomed.’ So the enemies were lined up at the gates, launching lit arrows over the walls. The women and children were screaming and the entire kingdom thought everything was lost, but then my father …”