10) Australornis lovei
Most of the time, I'm not really immersed into Cenozoic seabirds, but there was two things that attracted me about Australornis, discovered in the Waipara Greensand Formation. One was that it was a unique seabird in relation to evolutionary history. Also, it was found in one of the most prosperous fossil finds for seabirds: the continent of Zealandia....of course all that remains are just two islands, but before it was submerged 23 million years ago, there used to be a massive landmass that was connected to Australia and Antarctica that broke off in a span of 60-130 million years ago. As a result, animals especially seabirds that used to travel from different continents were stranded on Zealandia and had to readapt to the new land, evolving into unique ecological niches.
The time is 58 million years BCE and on the shores a three foot long grey-blue colored bird resembling today's little blue penguins, weighing 4 pounds waddles the rocky Paleocene shore outcrop like a penguin. However its appearance can be deceiving due to the presence of wings as it approaches a green-blue tidal pool and splashes into the water's surface, utilizing its appendages to trap some fish that have previously strayed from the sea. One is quickly snatched and gobbled up down the gullet like one would see a modern-day heron do to a fish. Suddenly, a resident Waimanu approaches from above, squawking at the intruder for invading its territory. With that, the Australornis lifts off in time and attempts to scour the ancient shoreline, searching for any potential feeding grounds to plunder.
So was it a proto-penguin that actually flew and used its specialized wings as natural fish trappers, but ended up losing to the bottom dwellers in the natural selection race? It's hard to tell due to the difficult diagnosis of the specimen. In fact there only remains a humerus, a scapula, and a few other wing bones so it's hard to tell whether if it actually was part of the penguin lineage at all. In fact it lacks the foreshortened and widened ulna and scapula that would be usually found in modern-day penguins, making phylogenetic analysis an unresolvable engagement. However it was compared with Late Cretaceous seabirds like Polarornis and Vegavis from Antarctica and they do look similar due to the fact that at the time, Zealandia was closer to Antarctica during the early Paleocene. Thus it wouldn't be a surprise if the ancestors of Australornis branched off from these mysterious birds and somehow made a footing in Zealandia not to mention even survive the K-T extinction that wiped out their non-avian cousins back in Antarctica. Now those are some badass birds.
Cited
G. Mayr & R. P. Scofield (2014) First diagnosable non-sphenisciform bird from the early Paleocene of New Zealand. Journal of the Royal Society of New Zealand (advance online publication)
9) Protoazin parisiensis
Hoatzins. Who doesn't love these strange, stinky, and arboreal Amazonian birds? Even the hooked hands observed on hoatzin chicks resemble those of the famous Archaeopteryx that reinforces the direct bird-dinosaur link so the hoatzin would actually be a living dinosaur. How cool is that? Anyway the modern-day hoatzin Opisthocomus hoazin is the only species in its own family of Opisthocomidae that is currently under constant study and debate over its relations to other birds. Some say it should be on a distinct family lineage of its own while others state that the hoatzin might be imbedded within Order Cuculiformes which include turacos, cuckoos, and roadrunners. Regardless, the hoatzin itself is a mysterious avian whose origins were currently thought to have been endemic to the New World, but not one, but TWO hoatzin discoveries suggest otherwise. In fact if we transported a group of these birds to its habitat in modern times, these birds would be a sanitary hazard, crapping their manure-like waste all over a iron tower not to mention out-eating the local pigeons in baguette crumbs thrown at them. Can't figure out the location? The following will explain:
The first one examined by German and Austrian paleoornithologists was actually found 100 years earlier and has only begun to be recognized as a very important species in the hoatzin's ancestry. Named Protoazin parisiensis this bird lived 34 MYA during the late Eocene in what is now Paris, France. However this doesn't explain how this bird, its modern descendants famous for its clumsy flight, ever made it across the Atlantic Ocean and into the heart of Amazonia. That's what the next discovery will solve.
Later 14 MYA from our French oddball into the middle Miocene lived another hoatzin ancestor named Namibiavis in what is now Kenya. It wasn't the only hoatzin in the neighborhood. In fact its relatives like Hoazinavis and Hoazinoides have already reached South America in present-day Colombia. So Africa, not Europe provided a quick route for hoatzins to enter the New World without sacrificing tons of energy travelling from Europe. So now that the hoatzin road trip has been completed, what happened to its Old World relatives? It turns out that a minor mass extinction happened between the Eocene and Oligocene epoch and played a role in their demise. Though not fully studied, this extinction may have been caused by extreme cooling of the Earth's climate (different from today's situation). This change in temperature cleared out large swaths of tropical rainforests in the Northern Hemisphere, the proto-hoatzins' habitat and exposed their vulnerability to ground predators below. I think that the constant tropical equator in South America actually provided a hot refuge for the South American hoatzins while relatives back in the Old World lacked this sort of geothermal heat conditioner. It also didn't help the early European hoatzins that new and faster carnivorous predators that could climb trees were arriving to Europe from Asia that put their vulnerable chicks in danger so that may have played a part in Protoazin's extinction.
Before reading about the hoatzin, I knew nothing about its evolutionary history. Now there's a lot to appreciate about this smelly yet interesting avian's story across geological time and a need to preserve this living relic of evolution whose habitat is currently under pressure from deforestation. With so many unsolved questions to answer and upcoming genomic analyses to be revealed, I believe this bird deserves a place in my list for just being a survivor.
Note: That's funny Gerald Mayr actually appeared in the bird at number 10 in my list. He must be a pretty famous paleoornithologist.
Cited
De Pietri, Vanesa L., Mayr, Gerald (2014) Earliest and first Northern Hemispheric hoatzin fossils substantiate Old World origin of "Neotropic endemic", Naturwissenschaften, Springer-Verlag Berlin Heidelberg 2014.
Mayr, Gerald (2014) A hoatzin fossil from the middle Miocene of Kenya documents the past occurrence of modern-type Opisthocomiformes in Africa. Auk 131: 55-60.
8) Bandringa shark nursery
After hurting my head with paleoornithology, I think it's a great time to turn to prehistoric sharks. I have somewhat a cozy interest in prehistoric sharks especially the famous giant Megalodon (though that Discovery Channel fakumentary last year did get my nerves especially how the network responded after viewers were outraged by this garbage). However sometimes Megalodons have to grow up somewhere and Panama was no exception where numerous teeth of juvenile Megalodons were found, suggesting that they lived on small prey such as sea turtles and dugongs before venturing into open waters to take on massive whales. However this shark nursery trait actually originated back further back in time even before the Age of Dinosaurs as scientists in what is now Grundy County, Illinois have uncovered.
The time is 300 million years BCE and after a perilous journey from a terrestrial river, a long-snouted ten-foot long Bandringa swims into a lush and yellow seagrass habitat within a shoreline delta. It is a female and she is fully pregnant with fully-developed egg cases. A thick and protected area like this would protect its young from open sea predators, but the sea scorpions that make this habitat home would find this easy platter delightful. She finds a suitable patch of seagrass for her cargo and she then ejects one egg case on top of the grass tips, sticking onto them like glue. The egg case resembles a corkscrew, providing hard and exterior protection, deterring those pesky eurypterids that attempt to make an omelet out of it. After that, the female Bandringa lays six more cases in various locations in the habitat and swims back into the mainland where it will die. Meanwhile an egg case from a previous mother hatches as the pup wiggles its way, using its long snout as a case opener. Once out of its former cocoon, the little four-inch long Bandringa pup will swim its way into the open waters where it will develop and hunt until it will return to the freshwater river on land to mate and return to the same delta nursery where it hatched years ago. Such is the miracle of life.
This speculative account isn't too far off from the actual finds. In fact paleontologists once thought there were two species of Bandringa: B. rayi that lived in freshwater habitats and B. herdinae that lived in saltwater habitats like the ocean. It was only after they compared the two species' anatomy that scientists realized that they were the same species and the specimens revealed an almost complete life history of the sawfish-like elasmobranch. The differences between the two groups might have been how each group was preserved in the fossil record. For example, bone and cartilage is usually preserved in freshwater fossils while soft tissue is preserved in saltwater fossils. Such rapid burial circumstances have been beneficial in revealing these unknown sharks to the scientific community. In addition, the number of juveniles in the saltwater habitat confirms that they did live in a nursery site and actually endured a migration back to freshwater to mate almost like today's salmon. Paleontologists have also found physical features such as downward-directed jaws specialized for hunting bottom feeders and some preserved sensory organs to help the animals detect prey in murky waters. Overall this find further brings the behavior of sharks bearing eggs in nursery sites back to the Carboniferous Period where from that point most modern sharks follow this mode of reproduction. On the other hand, Bandringa's look-alike "descendants" the sawfish's sex life is currently unknown. It also doesn't help that it's the most endangered elasmobranch group in the world in a recent study. How long will it be when overfishing and climate change will take its toll on these great survivors of the deep? Sorry to leave on a depressing note by the way, but what can I say?
Cited
Lauren Cole Sallan & Michael I. Coates. 2014. The long-rostrumed elasmobranch Bandringa Zangerl, 1969, and taphonomy within a Carboniferous shark nursery. Journal of Vertebrate Paleontology 34(1): 22-33
Pimiento C, Ehret DJ, MacFadden BJ, Hubbell G (2010) Ancient Nursery Area for the Extinct Giant Shark Megalodon from the Miocene of Panama. PLoS ONE 5(5):
http://www.iucn.org/?14311/A-quarter-of-sharks-and-rays-threatened-with-extinction
7) Atopodentatus unicus
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EVOLUTION we need to talk. I know you've been known to go bonkers while producing organic oddities, but what the hell is that? I'm sorry it looks you've chopped off the snout of a plesiosaur with the teeth intact and transplanted it on top of the head of a seal-like marine reptile with the face of a baleen whale. You make the Flish from The Future is Wild look like chum compared to this thing. From this point evolution, I'm going to prescript you some pills to help stave off your rampant and disorderly speciation disorder and I hope I don't see you in my office about this again.
Ok honestly I didn't know what to make of it when I saw this structure. I thought it could be a filter feeder like today's whales and dolphins, but right now lets see if I can clear the mystery hype by writing about this unusual reptile. So Atopodentatus lived back in China during the middle Triassic. Back in the day Pangaea was still a large landmass and shallow seas surrounded it all year right, but it also experienced a large diversity boom in marine reptiles. In China, you could find the earliest forms of nothosaur, plesiosaur, pachypleurosaurs like Keichousaurus, and mixosaurs, a type of small ichthyosaur swimming in these depths. Our celebrity, on the other hand really doesn't fit in those categories. In fact at this moment it's considered a basal sauropterygian though I'm not sure why the scientists haven't considered possibly classifying Atopodentatus as a specialized thallatosaur.
So now we get to the comb-like "teeth": what were they used for? The publishers consider two possibilities, one is filter-feeding, my early hypothesis and the other is for shoveling the ocean floor for invertebrates like sea worms. This behavior has been observed in grey whales off the coast of California It's easy to conclude that for the appearance of the maxilla that it was poorly specialized in catching fast-moving fish unlike the nothosaurs and did not have the tough and circular teeth for crushing shellfish as the placodonts. Therefore Atopodentatus must have occupied a unique niche in the Triassic marine ecosystem that could have endured its survival. However unless we find a worm or fossilized diatoms within its fossilized stomach, we haven't got a clue on what this reptile ate. Interestingly why hasn't anyone speculate that this "jaw" might have not been used for feeding, but maybe for sexual display? I know it sounds a little far off, but we've seen animals carry strange and unusual ornaments that are primarily not used for means of prey dismantlement or defense all the time such as Cretaceous edmontosaurs or modern-day peacocks. I could picture two atopodentatuses (that's the plural form I'm using in this article) locking their upper "jaws" in a gridlock while the two males smack each other's sides with their strange hoofs in order to push one of them off the rocky ledge into the shallow waters resembling the combat of today's elephant seals. Again it's pure speculation, but not impossible. So kudos to this strange Triassic animal whose name I won't bother remembering after publishing this article.
Cited
Long Cheng, Xiao-Hong Chen, Qing-Hua Shang & Xiao-Chun Wu (2014). A new marine reptile from the Triassic of China, with a highly specialized feeding adaptation. Naturwissenschaften (advance online publication)
6) Gobivenator mongoliensis
Finally I've reached dinosaurs. January has only produced a few dinosaurs like some named titanosaurs and enantiornithi, a possible abelisaur from Late Jurassic Portugal from a few teeth, and an unnamed megaraptoran from Late Cretaceous Brazil. There were also anatomical analyses such as the aerodynamics of Microraptor, the osteology of the carcharodontosaurid Tyrannotitan, and the endocranial morphology of the abelisaurid Aucasaurus to name a few. But the most significant find of January I can say is an almost complete skeleton of a troodont. When the first representative of the family Troodon was discovered, paleontologists prior to the Dinosaur Reinassicance considered them either lizards or sometimes from only their strange teeth, the butt-headed pachycephalosaurs! Now we know troodonts are a distinct group from deinonychosaurs and are actually more closely related to birds than their non-avian counterparts. Also, complete specimens such as Mei long and Sinornithoides demonstrated that troodonts roosted like modern birds and even brooded eggs in their care.
Though most troodont skeletons are scrappy, Gobivenator was no exception consisting of a preserved skull and an almost complete skeleton with the exception of cervical vertebrae, hindlimb and forelimb bones, and gastralia. Another important anatomical aspect is the previously unknown troodont palate, a bone found in the back part of the nasal cavity that closely resembles those of basal birds like Archaeopteryx, further establishing the direct troodont-bird link. It lived 72 MYA in the Djadokhta Formation in what is now Mongolia. It may have lived alongside other troodontids like Byronosaurus and Saurornithoides and Gobi desert celebrities such as Protoceratops, Pinacosaurus, Oviraptor, Shuvuuia, plus the infamous Velociraptor. Gobivenator's place in the Late Cretaceous food chain will remain a mystery until more discoveries are made.
Alas a complete skeleton of a troodont sounds nice to me even though they lack the public popularity as their ferocious dromaeosaur counterparts. In fact I'm looking forward to more specimens of former Troodon that were lumped into this genus to be divided into different species. This happened before to dinosaurs named under Iguanodon and Megalosaurus so to me, I expect a future of newly christened troodonts.
Cited
Takanobu Tsuihiji, Rinchen Barsbold, Mahito Watabe, Khishigjav Tsogtbaatar, Tsogtbaatar Chinzorig, Yoshito Fujiyama & Shigeru Suzuki (2014). An exquisitely preserved troodontid theropod with new information on the palatal structure from the Upper Cretaceous of Mongolia. Naturwissenschaften. (advance online publication)
5) Machaeroprosopus lottorum
It is 205 MYA BCE and a female phytosaur tears into a dicynodont carcass that has been killed by a Poposaurus two days ago, submerged halfway into mud. It has been two months since she made her last kill and she makes no hesitation, eating the corpse. The oxbed lake that she once strived in is now dried out due to a merciful heat wave. She must locate a large patch of shade soon or risk the danger of overheating her entire body. Suddenly from behind, one of her own kind stalks toward her from behind. From the large knob on its head, it turns out to be a male Machaeroprosopus that has gained interest in the female. Though this time of year is not usually mating season, the male instead gives a low frequency gurgle to the feasting female in front of him. The female turns around and responds with a high hiss at the intruder. The male realizes he needs to step up his game and starts bobbing his head horizontally, showing off his bright aqua-green bony crest to the female. The female just turns away, disinterested in this young male and to the other side of the corpse to feed undisturbed. The impatient male then approaches her swiftly in an attempt to copulate her from behind, but this will prove to be his biggest mistake. The female's head flashes back at the male and her jaws snap around the male's head, locking them shut like a mousetrap. The male growls in surprise and anguish as he tries to throw the female's lock off by swinging its head side-by-side. Luckily the ordeal lasts for five seconds when the female loses her grip and snaps at the air surrounding the male and lets out a booming roar resembling the sound of a blender. With a few minor scratches on its armored head and its delicate ornament, the male skulks away in defeat as a result of his incompetence as the female "celebrates" her independence by dragging the light carcass with her jaws to a nearby pool. But both phytosaurs do not comprehend that tomorrow morning, a massive thunderstorm will arrive and create flash floods that will bury these two archosaurs locked in sediment for eternity until now.
Now I chose this animal, not because it had a big news press, but because it actually relates to an e-mail I had earlier. My academic advisor Jonathan Weinbaum studied paleontology and actually graduated from Texas Tech University where the scientists who discovered the phytosaur remains also originated. When I first saw the press release, I immediately sent it to him, asking if he was familiar with them in the past. In a reply, not only did he assist in excavating one of the skulls, he also made the cast of the phytosaur in the background of the case in the linked video! How cool is that?
Believe it or not there are actually SEVERAL species of Machaeroprosopus, but most of them were reassigned to other phytosaur species. So how could scientists tell that this phytosaur was an entirely different species? By comparing the snout, bones in the hind end of the skull, and a head opening called the supratemporal fenestra to other phytosaur skull fossils, they concluded that their finds were different from their counterparts thus a new species was described. The Texas Tech scientists have also suggested that a previously named phytosaur Redondasaurus might actually be a synonym for Machaeroprosopus. Other than that, I find it very lucky for these almost complete phytosaurs to be discovered in good shape as this further deepens our paleobiological knowledge of these crocodilian-like archosaurs. Ok to address those who are new here, the main difference between a phytosaur and a crocodile is that the nostril is found further near the orbits in a phytosaur than a croc whose visible nostrils are on the tip of the snout. Sometimes convergent evolution can play tricks with our minds when making modern-day to prehistoric comparisons.
Cited
Axel Hungerbühler, Bill Mueller, Sankar Chatterjee and Douglas P. Cunningham (2012). Cranial anatomy of the Late Triassic phytosaur Machaeroprosopus, with the description of a new species from West Texas. Earth and Environmental Science Transactions of the Royal Society of Edinburgh, 103, pp 269-312.
http://youtu.be/LuYZo5boGVY
http://today.ttu.edu/2014/01/researchers-uncover-new-species-of-prehistoric-reptile/
4) New makeup for Beelzebufo ampinga
Original estimates put the monster frog around a whopping sixteen inches, but the most complete specimen found is actually seven inches though there's some bones that suggest Beelzebufo might have reached nine inches. Also, contrary to popular depictions, a frog with such a huge head and heavy armor wouldn't permit it to hop! Instead it probably crawled on the ground, taking out small prey, but rarely majungasaur chicks as popularly depicted.
Finally, there is a lot of morphological evidence from what the scientists could gather that would suggest Beelzebufo came from a South American anuran family called Ceratophryidae. This branch includes the infamous Argentine horned frog that doesn't hesitate, gobbling any prey from large spiders to members of its own kind even to the point of suffocation. Just watch this Most Extreme episode from 40:36 to the end of the video to watch how our mouths have to be if we want to eat like an Argentine horned frog
Anyway this further supports the existence of a land bridge between South America and Madagascar before it became submerged 112 MYA and isolated the latter island to its own evolutionary fate. It's nice to see the "frog from hell" get an update, but what if there were other massive frogs from the Mesozoic and beyond undiscovered in the fossil record? If you thought cane toads with their high reproduction rates and poisonous glands were scary enough, imagine more devil frogs running around in our time. Syfy movie anyone?
Cited
Evans, S., Groenke, J., Jones, M., Turner, A., Krause, D. 2014. New material of Beelzubufo, a hyperossified frog (Amphibia: Anura) from the Late Cretaceous of Madagascar. PLoS One. 9 (1).
http://phenomena.nationalgeographic.com/2014/01/29/fossil-frog-from-hell-gets-a-new-look/
3) Dormaalocyon latouri
From the beginning of this new year, I was expecting a new issue of the Journal of Vertebrate Paleontology with a new amazing discovery and boy it did not disappoint. Not only was there a discovery of an early ancestor of the entre Carnivora mammalian lineage, but it might have suggested that lions, tigers, and bears' ancestors originated in Europe. Named Dormaalocyon after the site of Dormaal, a tiny town in Belgium, this strange predator, resembling a cross between a cougar and a squirrel lived 55 MYA in the boundary of the Paleogene and Eocene epochs. Back then there were massive changes going on including the P-E Thermal Maximum in which the global temperature rose to a historical high, influencing climates and biodiversity everywhere including extensive rainforests and the body sizes of mega reptiles such as Titanoboa and Barbaturex the Burmese Lizard King. It also created the humid, subtropical forests in Belgium that our cat acquaintance calls home. From the ankle bones and the long prehensile tail, this mammal was arboreal and likely fed on insects and small mammals like modern-day kinkajous and civets. There were also tons of "baby teeth" and molars found possibly, in my opinion another mammal nursery? Only more discoveries will tell.
On a phylogenetic perspective, Dormaalocyon is on the basal branch behind most other carnivoraforms and is closely related to the North American Miacis and Vulpavus. This, in turn would suggest that primitive carnivoraforms had to originate from Europe to North America through means of an accessible and temporary land bridge such as Greenland due to low sea levels. Fossils like this are a rarity since a majority of fossil animals are usually herbivores and omnivores due to the trophic pyramid. Since carnivores are high on the pyramid, they are less likely to be preserved in the fossil record than those below including herbivores and omnivores. A lucky find like this changes our understanding on the origins of modern mammalian carnivores right in their moment of diversification as other previous sites such as North America and China had only scant carnivoraform remains to understand their evolutionary journey. So next time when your cat, dog or ferret suddenly wakes you up in the morning by jumping on your bed (I've had that occasion happen to me every week), remember to thank that little Flemish guy in the Eocene for making your life a lot easier to enjoy.
Cited
Sole, Floreal. "Dental and tarsal anatomy of ‘Miacis’ latouri and a phylogenetic analysis of the earliest carnivoraforms (Mammalia, Carnivoramorpha)" (2014). Journal of Vertebrate Paleontology. 34(1):1-21.
2) Prehistoric sea monsters get their black streaks (Only three so far)
It's cool that we're able to almost figure out what colors a few dinosaurs actually beared (those by the way were feathered), but what about other prehistoric beasts? A flying pterosaur like Tapejara couldn't have been dull grey especially with that large crest on its head to attract potential mates and a synapsid like Edaphosaurus might have used its colorful sail to flash out at rivals or distract predators. But this new discovery takes us further not on land, but into the depths of the primeval ocean.
Mesozoic sea monsters have been prospering in this golden age of paleontology. Their paleobiology such as the plesiosaurs' long necks and reproduction methods like live birth are being reexamined and new significant discoveries are being made very year. Mosasaurs, especially have been given a tail fluke reconstruction due to a recent Prognathodon specimen found in Jordan. Now an 86-million-year-old mosasaur, along with a 55-million-year-old leatherback turtle and a 190-million-year-old ichthyosaur will have their colors revealed for the first time.
These three were examined because of the presence of "black halos" around their bones originally thought to be microbial contamination or remnants of skin. They were reexamined and to the surprise of scientists, they were partially validated as preserved melanosomes, oval-shaped groups of pigments that give hair, skin, and feathers their visible color. Their miraculous preservation was probably due to a small pigment called eumelanin, a black pigment that can survive long periods of time in any environment. In order to fully confirm the presence of melanosomes, scientists employed an X-ray technique called energy-dispersive X-ray microanalysis. By reading its chemical composition, the analysis confirmed that the melanosomes were not aligned with the matrix around them so the microbial contamination hypothesis was thrown under the mat. Therefore all three specimens had partial or completely black coloration in the times that they lived.
After all of this, paleontologists have tried to come up with explanations why these reptiles wore these colors starting with the easiest: leatherback turtles. Modern-day leatherbacks are one of a few reptiles whose scales lack β-keratin, a keratin that usually gives reptiles their rigid and waterproof skin, a trait that leatherbacks do not need in a marine environment. Leatherbacks are also countershaded, meaning that while black pigment covers the upper portion of their body, lighter colors like white shade the underbelly. This natural texture helps these turtles travel across almost every ocean on Earth, especially cold areas than their tropical cousins. They also bask during the daylight hours, raising their body temperatures as a result of their black pigments absorbing UV light. This couldn't be done if the leatherbacks were lightly colored. With this increased heat surplus, leatherbacks can be able to dive and stay in the abyss for hours, hunting their primary diet of jellyfish. Marine reptiles in the past might have used this ancient technique to dive after deeper prey. There is also the extra bonus of not getting sunburned skin with a black-colored surface. If these marine reptiles survived into this time, we'd might design our sunscreen lotions after the biomechanics of the mosasaur skin texture. Take that Banana Boat!
It was also found that the mosasaur specimen also had the same countershaded texture as leatherbacks and modern-day great white sharks. This predator might have used it, not for diving after squishy invertebrates, but for deep-sea camouflage. If it's swimming after a shoal of Hesperornis or plesiosaurs in open waters, the mosasaur can be able to swim parallel below them, revealing its dark texture. That way its unsuspected prey cannot be able to distinguish the murky depths from the actual predator, making the latter invisible. From that, the mosasaur, aided with a finned tail can propel itself into a swift ambush and deliver a savage attack from below. This technique has been observed in modern great whites and tiger sharks so it's not unreasonable for mosasaurs to exhibit this method of hunting behavior.
Finally, the ichthyosaur has found to be the most interesting case: most of its skin was surrounded by an envelope of dark skin, suggesting that these marine reptiles could be completely black. This coloration can aid them in deep-sea diving and hunting like modern-day sperm whales. And NO this does not indicate that Triassic kraken existed though it's a pretty fun fantasy to swing around. However it is important to note that not ALL ichthyosaurs are deep-diving and that they are found in diverse ocean niches so there is a possibility of rainbow spotted or striped ichthyosaurs leaping along the sides of your boat to greet you if you sped across a Jurassic sea 150 MYA.
Thanks to this discovery, the same techniques used on the specimens can possibly distinguish coloration on terrestrial fossilized fauna on whether or not they have melanosomes or microbial contamination. I'll look forward to more discoveries, dinosaur and not, in living color.
Cited
Johan Lindgren, Peter Sjövall, Ryan M. Carney, Per Uvdal, Johan A. Gren, Gareth Dyke, Bo Pagh Schultz, Matthew D. Shawkey, Kenneth R. Barnes, Michael J. Polcyn. Skin pigmentation provides evidence of convergent melanism in extinct marine reptiles. Nature, 2014
Lindgren, J.; Kaddumi, H. F.; Polcyn, M. J. (2013). "Soft tissue preservation in a fossil marine lizard with a bilobed tail fin". Nature Communications 4.
And the number one discovery of January 2014 is...
1) Tiktaalik pelvis!
I read on this year's spring TV guide to PBS that "Nova" will showcase a series called "Your Inner Fish" by Tiktaalik roseae discoverer Neil Shubin this April. I'm no stranger to this guy since I have his 2009 book "Your Inner Fish" and I found it very enlightening especially with the gene expressions in our embryologic stages and bony homologies. So when I came across this discovery from first glance, I found it soomewhat curious that this discovery was published months before his show will air so does it mean that Shubin will explain this new Tiktaalik discovery in the series? I'll look forward to it.
Anyway Tiktaalik who doesn't love this Inuit fish ancestor of ours? It's appeared in a few shows like Animal Armageddon and one with David Attenborough in it. Hell it even has a FREAKING theme song!
So now to the discovery. Shubin and his colleagues brought two blocks of the original specimen, covered in thick plaster back to the University of Chicago. The first block was extracted and unraveled through extensive handiwork through a few years and revealed the fishapod's iconic skull and front leg flippers plus other frontal remains. After those remains were shown to the world in 2006, Shubin and his team went straight to work on the second block and what they found would change how we look at Tiktaalik and the origin of terrestrial vertebrates forever. First, they only found some more fin bones and some other ribs, but then the jackpot came up: Tiktaalik's pelvis. Shubin and his colleagues knew that lobe-finned relatives closet to the tetrapod lineage documented had very tiny pelvises, but Tiktaalik's pelvis was unusually large for a animal not fully evolved for land. After comparing and scouring all of the remains that they brought back from the Arctic, Shubin's team realized that they had FIVE other pelvises that slipped under their eye since initially they didn't know what a Tiktaalik pelvis look like. The hip's shape also resembled those of land animals, suggesting not only did it swim, but it actually pushed its own body weight across mud flats and shallows, supported by a massive pelvis fin. However unlike later relatives, Tiktaalik still retained its fish-like anatomy since the hip isn't connected to the spinal cord. So even it did "walk" somewhat on land, it probably didn't use this type of locomotion more often. The discovery also highlights that the transition of vertebrates from water to land happened to swamps, not the classic sea-to-land cliché in outdated evolutionary textbooks.
Transition fossils have always been a treasure trove for paleontologists from Archaeopteryx to walking whales. Even if they are found and kept in a safe museum exhibit, that doesn't their cases are closed. We're still have a lot to learn about their paleobiology and their mechanics plus possibly find older relatives that predate them to create new versions of telling their evolutionary stories. This is the process of science and Tiktaalik's fame does not exempt it from this process. I congratulate Neil Shubin and his fellow scientists at this new discovery and I look forward to more revelations behind our favorite fish ancestor.
And that's why Tiktaalik's pelvis IS the top discovery of January 2014
Cited
Neil H. Shubin, Edward B. Daeschler, and Farish A. Jenkins, Jr. Pelvic girdle and fin of Tiktaalik roseae. PNAS, January 13, 2014
http://phenomena.nationalgeographic.com/2014/01/13/how-we-got-on-land-bone-by-bone/
Well guys that's my first post. If you see anything you wanted to ask or correct me on, please do not hesitate to leave any comments below or shoot me up an email at banzai94@sbcglobal.net. Also, if you want to review my blog's first post, feel free to do that. I want to let you know that this monthly special only happens once a month so I need to know something else to keep my blog updated. I was thinking about taking random questions on paleontology, but I think Dinosaur George has something like that, but what the heck. If there's any suggestions you'd like me to do for my blog or would like to post your own top 10 list, again contact or comment. Thank you all for giving me this chance to be well-known in the paleo-community and I'll hopefully get the next monthly special at the end of this month.
We are the local embodiment of a Cosmos grown to self-awareness. We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose. Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive is owed not just to ourselves but also to that Cosmos, ancient and vast, from which we spring.
-Carl Sagan Cosmos
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