From the size of the ocular cavities and the proportions of the skull, paleobiologists can say, with a fair degree of confidence, that baby dinosaurs were “really cute”.

Yes, that’s a technical term.

Learned at: Dino 101: Dinosaur Paleobiology (Alberta/Coursera)

Extra credit: http://www.theguardian.com/science/2013/oct/22/beautiful-baby-dinosaur-delights-palaeontologists

Archaeopteryx 

A bird that lived during the Late Jurassic period that is a transitional species between feathered dinosaurs such as Velociraptor and Anchiornus, and modern birds. The feather impressions found on archaeopteryx are advanced flight feathers, and suggest feathers began evolving well before the Late Jurassic. Also, this fossilized version is super creepy and super cool.

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Today is so exciting for a ton of fellow palaeontologists, students, researchers, and myself… Dreadnoughtus has finally been published!

The video above gives you guys a bit of history to where this titanosaur was discovered back in 2005. Almost ten years later and it’s finally gone public! With a name like Dreadnoughtus, it’s hard not to want to run around saying its awesome name.

These fossils spent a lot of time being excavated out of the matrix they were found in; around 4 years with multiple labs working tirelessly to clean and repair them. We had to get it done at least in some sort of quick time, right? With such a huge specimen, a lot of man power is required!

I’m so proud and happy for everyone involved that we can now share this gorgeous dinosaur to the public! It’s MASSIVE. The fossils are just mind blowing to look at, and now we continue to move forward with its preservation, education, and further research. It’ll be going back to Argentina next year.

You can read the article about Dreadnoughtus here on Drexel University’s website, and the scientific paper on Nature.com (which some super awesome people I know worked on).

[Image: A flock of Hatzegopteryx. One paces along on all fours, another rockets into flight by pushing off with its strong forelimbs, and the rest soar above them.]

Pterosaur Myths Busted (V3)

Pterosaurs are a staple of movies featuring prehistoric animals—yet most media depictions of the poor beasts remain woefully stuck in the 19th century. Real pterosaurs were just about nothing like the sluggish, flimsy-winged gliders that populated our childhood picture books and movies. Here we take a look at how some common misconceptions about them stack up against the facts. 

Misconception: “Pterodactyl” and “pterosaur” mean the same thing.

Fact: “Pterosaur” applies to the entire group, but “pterodactyl” is only correct when you’re referring to, well, pterodactyloids.

In general, pterodactyls had proportionally shorter tails, longer necks, bigger heads, and longer hand bones than non-pterodactyls. Compare these skeletal drawings of Rhamphorhynchus (a non-pterodactyl) and Pteranodon (the ’dactyl of Jurassic Park fame).

M: Pterosaurs were dinosaurs.

F: Dinosaurs fall under the orders Ornithischia and Saurischia. Pterosaurs do not belong to either group, though current evidence places them as close relatives of the dinosaurs within Ornithodira

M: Pterosaurs were the ancestors of birds.

F: Like their cousins Velociraptor and T. rex, birds are a type of theropod dinosaur. Pterosaurs left no living descendants.

M: Pterosaurs had scaly / leathery / bald skin.

F: Though the pads of their feet were scaly, most of a pterosaur’s body was covered in hairlike filaments called pycnofibers. Pterosaurs of the primitive family Anurognathidae, such as the one shown below, seem to have been fluffed up from snout to tail with pycnofibers.

M: Pterosaurs were “cold-blooded.”

F: Nope. With no body heat to insulate there wouldn’t be much point to pycnofibers.

M: Pterosaurs could pick things up with their feet.

F: Their feet were much better suited to walking than grasping. Like humans, they had plantigrade feet—in other words, the entire sole of the foot contacted the ground as they walked.

M: Grounded pterosaurs walked on their hind legs / could only crawl around on their bellies.

F: Pterosaurs usually walked on all fours, and many were quite adept at ground locomotion to boot, especially the pterodactyls. Some, such as the dsungaripteroids, may even have been capable of galloping. The three in the illustration below are shown badgering an azhdarchid for its kill.

M: All pterosaurs had teeth / were toothless.

F: Pterosaurs had all kinds of dental arrangements, from completely toothless to jaws positively bristling with the things—just look at Pterodaustro below. (Pteranodon was toothless, by the way; its name even means “toothless wing.”)

 

M: Females of crested species had large head crests like the males.

F: Head crests were probably sexually dimorphic, with males usually having much larger, more elaborate head decoration, as demonstrated by these two Darwinopterus

M: Pterosaur wing membranes were leathery, flimsy and prone to tearing.

F: Pterosaur wings were supple, complex, multilayered structures. They were reinforced with closely-packed fibers called aktinofibrils. 

M: Each wing was supported by several fingers like a bat’s.

F: Only the hugely elongated fourth finger supported the wing; the other three fingers were much smaller. See here for a diagram of the pterosaur wing. 

M: Pterosaurs had sharply-pointed wing tips.

F: Such a wing shape would have made flight difficult. Here’s our anurognathid friend again, showing off its nice rounded wing tips for you.

 

M: Some pterosaurs were too big / heavy to fly.

F: Even the largest pterosaurs were probably capable of powered flight. 

M: Pterosaurs could only take off by falling from a cliff / tree / [insert high starting point here].

F: They could launch into flight under their own power using all four limbs, a strategy also known in some modern bats. This is called “quadrupedal launch” (or just “quad launch”). See this video for a pterosaur quad launch demonstration.

M: All pterosaurs were ocean-going fish hunters.

F: They occupied a variety of niches, and many lived inland.

M: Pterosaurs cared for their hatchlings in much the same way as modern birds.

F: Other than protecting them during the hatching process, pterosaur parents might not have had much to do with their offspring (called “flaplings”) since they could probably fly almost immediately after birth.

Recent findings reveal that at least some pterosaurs, such as Hamipterus, were social and may have built their nests together in huge colonies.

M: Pterosaurs went extinct because they were outcompeted by birds.

F: The evidence for this idea is weak at best.

M: Live pterosaur sightings prove that pterosaurs never really went extinct. 

F: This idea relies on scant evidence as well. 

—————

If you have anything more than a passing interest in pterosaurs, you really should pick up a copy of paleontologist Mark Witton’s book on themPterosaur.net is another useful resource of information about these fascinating, ridiculous creatures.

Sources to avoid include David Peters’ Pterosaur Heresies and ReptileEvolution.com. While these sites seem professional on the surface and feature loads of attractive artwork, scientists have been unable to replicate the results of Peters’ research, and repeatable results are a hallmark of good science. Read more about Peters here (PDF), here and here

(Credit: Skeletal drawings by Scott Hartman; all other illustrations by Mark Witton.) ( #long post )

The Origin of Humans Is Surprisingly Complicated

Human family tree used to be a scraggly thing. With relatively few fossils to work from, scientists’ best guess was that they could all be assigned to just two lineages, one of which went extinct and the other of which ultimately gave rise to us. Discoveries made over the past few decades have revealed a far more luxuriant tree, however—one abounding with branches and twigs that eventually petered out. This newfound diversity paints a much more interesting picture of our origins but makes sorting our ancestors from the evolutionary dead ends all the more challenging.

Source: Scientific American

In an opinion piece in today’s New York Times, Michael Novacek, the Museum’s Provost of Science and a Curator in the Division of Paleontology, writes about Prehistory’s Brilliant Future

"Here we are, in the age of the microchip and the Mars explorer, and yet some of our most exciting and extraordinary scientific discoveries are extinct species in Earth’s fossil record."

Read the full piece in the New York Times

Feathers close up (stock image). The researchers’ hypothesis: The evolution of feathers made dinosaurs more colorful, which in turn had a profoundly positive impact on communication, the selection of mates and on dinosaurs’ procreation.

Credit: © thawats / Fotolia

[Click to enlarge image]

Why were dinosaurs covered in a cloak of feathers long before the early bird species Archaeopteryx first attempted flight? Researchers from the University of Bonn and the University of Göttingen attempt to answer precisely that question in their article “Beyond the Rainbow” in the latest issue of the journal Science. The research team postulates that these ancient reptiles had a highly developed ability to discern color. Their hypothesis: The evolution of feathers made dinosaurs more colorful, which in turn had a profoundly positive impact on communication, the selection of mates and on dinosaurs’ procreation.

The suggestion that birds and dinosaurs are close relatives dates back to the 19th century, the time when the father of evolutionary theory, Charles Darwin, was hard at work. But it took over 130 years for the first real proof to come to light with numerous discoveries of the remains of feathered dinosaurs, primarily in fossil sites in China. Thanks to these fossil finds, we now know that birds descend from a branch of medium-sized predatory dinosaurs, the so-called theropods. Tyrannosaurus rex and also velociraptors, made famous by the film Jurassic Park, are representative of these two-legged meat eaters. Just like later birds, these predatory dinosaurs had feathers — long before Archaeopteryx lifted itself off the ground. But why was this, particularly when dinosaurs could not fly?

Dinosaurs’ color vision

"Up until now, the evolution of feathers was mainly considered to be an adaptation related to flight or to warm-bloodedness, seasoned with a few speculations about display capabilities" says the article’s first author, Marie-Claire Koschowitz of the Steinmann Institute for Geology, Mineralogy and Paleontology at the University of Bonn. "I was never really convinced by any of these theories. There has to be some particularly important feature attached to feathers that makes them so unique and caused them to spread so rapidly amongst the ancestors of the birds we know today," explains Koschowitz. She now suggests that this feature is found in dinosaurs’ color vision. After analyzing dinosaurs’ genetic relationships to reptiles and birds, the researcher determined that dinosaurs not only possessed the three color receptors for red, green and blue that the human eye possesses, but that they, like their closest living relatives, crocodiles and birds, were probably also able to see extremely short-wave and ultraviolet light by means of an additional receptor. "Based on the phylogenetic relationships and the presence of tetrachromacy in recent tetrapods it is most likely that the stem species-of all terrestrial vertebrates had photo receptors to detect blue, green, red and uv," says Dr. Christian Fischer of the University of Göttingen.

This makes the world much more colorful for most animals than it is for human beings and other mammals. Mammals generally have rather poor color vision or even no color vision at all because they tended to be nocturnal during the early stages of their evolution. In contrast, numerous studies on the social behavior and choice of mates among reptiles and birds, which are active during the day, have shown that information transmitted via color exerts an enormous influence on those animals’ ability to communicate and procreate successfully.

Feathers allowed for more visible signals than did fur

We know from dinosaur fossil finds that the precursors to feathers resembled hairs similar to mammals’ fur. They served primarily to protect the smaller predatory dinosaurs — which would eventually give rise to birds — from losing too much body heat. The problem with these hair-like forerunners of feathers and with fur is that neither allow for much color, but tend instead to come in basic patterns of brown and yellow tones as well as in black and white. Large flat feathers solved this shortcoming by providing for the display of color and heat insulation at the same time. Their broad surface area, created by interlocked strands of keratin, allows for the constant refraction of light, which consequently produces what is referred to as structural coloration. This refraction of light is absolutely necessary to produce colors such as blue and green, the effect of metallic-like shimmering or even colors in the UV spectrum. “Feathers enable a much more noticeable optical signaling than fur would allow. Iridescent birds of paradise and hummingbirds are just two among a wealth of examples,” explains Koschowitz.

This work means we must see the evolution of feathers in a whole new light. They provided for a nearly infinite variety of colors and patterns while simultaneously providing heat insulation. Prof. Dr. Martin Sander of the University of Bonn’s Steinmann Institute summarizes the implications of this development: “This allowed dinosaurs to not only show off their colorful feathery attire, but to be warm-blooded animals at the same time — something mammals never managed.”

Story Source:

The above story is based on materials provided by Universität Bonn. Note: Materials may be edited for content and length.

Journal Reference:

  1. M.-C. Koschowitz, C. Fischer, M. Sander. Beyond the rainbow. Science, 2014; 346 (6208): 416 DOI: 10.1126/science.1258957

Fascinating!  Really, this got me thinking big time.

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Spinosaurus was weirder than previously thought, according to new research

Stubby hind legs, a low, quadrupedal stance, and webbed feet for an aquatic life are among the features revealed by the discovery of new fossils of the dinosaur previously known from incomplete remains.

There’s been lots of media coverage about this story released today. National Geographic and the New York Times in particular have provided excellent content. Check them out to fill your head with juicy dinosaur knowledge.

There is also this cool video from the University of Chicago detailing the findings:

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aseantoo submitted to medievalpoc:

Xu Xing / 徐星

Photographs by Calum MacLeod, USA TODAY

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One of your fans, Cometkins, asked if you knew about any POC paleontologists.

The world’s most prolific discover of dinosaurs is a Chinese guy who’s been called a real-life Indiana Jones. 

He’s discovered at least 32 new species of dinosaurs. Also furthered loads of new theories about their connections with modern birds.

I also find him pretty damn cute.

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Why doncha come and dust off my feathers, baby. :)

Stunning fossil shows pregnant mare and fetus

Forty-seven million years ago, a pregnant mare and its unborn foal lost their lives, perhaps chased into a lake, where they drowned. Where they died, however, was a stroke of luck for 21st century paleontologists.

Read more (via Science/AAAS)