Dinovember 2016, Days 24-28

Wow, looks like I got behind again. Here's five dinosaurs in one go! Let's see...

Shuvuuia: what's so great about a pair of arms?

Name: Shuvuuia deserti
Meaning: desert bird
Time: Late Cretaceous, c 75 million years ago
Place: Mongolia
Size: about 60 centimetres (23.6 inches) long
Type of Dinosaur: parvicursorine alvarezsaurid (single-clawed bird-like dinosaur)

Shuvuuia is an odd little dinosaur, part of a group initially thought to be flightless birds. These fuzzy creatures had long, narrow snouts and tiny teeth and a single claw on their extremely shortened arms. A common idea is that they would have used their claws to open insect nests and then snarfed them up; sort of dinosaurian anteaters. Here, one Shuvuuia is preening another.

Deinocheirus: why stop at just a pair of arms?

Name: Deinocheirus mirificus
Meaning: peculiar terrible hand
Time: Late Cretaceous, c 72 million years ago
Place: Mongolia
Size: about 11 metres (36 feet) long and 6.3 tonnes (6.9 tons)
Type of Dinosaur: deinocheirid ornithomimosaur (weirdo ostrich dinosaur)

For many years, Deinocheirus was one of the great mysteries of palaeontology. A pair of powerfully-clawed forelimbs, 2.4 metres (7.9 feet) long, and nothing else. What were they from? Was it a carnosaur far larger than any other, opening up sauropods like tins of sardines? Was it one of those odd ground sloth-like therizinosaurs? The arms are actually very much like the ostrich dinosaurs' - perhaps it's one of those?

Turns out that the last one was right, but Deinocheirus wasn't just a big and bulky Struthiomimus, not at all. In 2014, complete skeletons of this mysterious monster finally were revealed to the world, and Deinocheirus was more bizarre than anyone imagined. Huge and bulky, with a towering hump on its back, a spoonbill, and a very deep lower jaw. Stomach contents preserve fish and gastroliths, showing an omnivorous diet. Wild, wild stuff.

A fine feathery face on a small forest herbivore.

Name: Agilisaurus louderbacki
Meaning: [geologist George] Louderback's agile reptile
Time: Middle Jurassic, c 168 million years ago
Place: southwest China
Size: about 1.2 metres (3.9 feet) long, but the known specimen may be a juvenile
Type of Dinosaur: neornithischian genasaur (primitive-advanced beaked dinosaur)

Agilisaurus louderbacki, like many dinosaurs, is only known from a single specimen. Fortunately, though, it's a very good one with virtually all the bones represented. It's a small beaked herbivore, and remains from Russia show that at least some of these dinosaurs had feathery coverings on their bodies, so I've restored Agilisaurus with such integument here.

Desert sky, dream beneath a desert sky, rivers run but soon run dry...

Name: Alamosaurus sanjuanensis
Meaning: San Juan [County, New Mexico, where it was discovered] Ojo Alamo [Formation] reptile
Time: Late Cretaceous, c 66 million years ago
Place: Texas, New Mexico, Utah; probably Wyoming and Mexico as well
Size: complete specimens about 20 metres long (66 feet) and 16 tonnes (17.6 tons) are subadult; fragmentary remains generally considered to be from Alamosaurus suggest sizes of 30 metres (98 feet) and more than 50 tonnes (55 tons)
Type of Dinosaur: opisthocoelocaudiine saltasaurid (column-handed advanced armoured long-necked dinosaur)

The only sauropod currently known from Late Cretaceous North America, Alamosaurus is undoubtedly one of the best animals ever. It lived right at the end of the Age of Reptiles, alongside T. rex, and grew to be one of the biggest land animals. More and more remains of this giant seem to be cropping up in recent years, and hopefully more will reveal what their growth and lifestyle was like.

There's something FISHY about little Liaoningosaurus...

Name: Liaoningosaurus paradoxus
Meaning: paradoxical Liaoning [Province, where it was discovered] reptile
Time: Early Cretaceous, c 122 million years ago
Place: northeast China
Size: 34 centimetres (13.4 inches) long; whether the described specimen is an adult or not is debated
Type of Dinosaur: ankylosaurid ankylosaur (armoured dinosaur)

Recently, Liaoningosaurus has gotten some attention as a new study suggests it was semiaquatic and fed on fish, as evidenced by fish remains in its stomach, and that the described specimen (apparently, many, many other ones are known) is actually a grown adult! These claims have understandably drawn criticism, and apparently the paper does not do a terrific job of making its case. However, I don't think we should readily dismiss these claims - it honestly seems like a very plausible niche for an ankylosaur to occupy, and as more fossils are described they'll help us understand just what the natural history of this odd little armoured dinosaur was...

Dinovember 2016, Day 21

It seems I have gotten a day behind in posting. Oh well, I'll just post them the day after then...

Kid, you got a lot of growing up to do.

Name: Abydosaurus mcintoshi
Meaning: [great sauropod specialist Jack] McIntosh's Abydos reptile [Abydos is the location where, in Egyptian mythology, the severed head and neck of the god Osiris were buried; this is in reference to the fact that several skulls of this dinosaur were discovered at the same site]
Time: Early Cretaceous, c 104.5 million years ago
Place: Utah
Size: the best specimen is a juvenile, so its adult size is unclear, but there are fragmentary remains from the site that indicate a potential large adult possibly as much as 30 metres (98 feet) long
Type of Dinosaur: brachiosaurid macronarian (tall-shouldered big-nosed long-necked plant-eating dinosaur)

In a nice little twist on the case of almost all other sauropod species, Abydosaurus mcintoshi is known from several good skulls and only a few parts of the postcrania. The type and best specimen is a juvenile but the site where it was discovered yielded bones from at least five individuals of varying ages and sizes. Here, a hypothetical adult is shown with a youngster. If you can tell by from the picture, I went with the adult have darker face stripes on some background mottling, while the juvenile is paler with faint face stripes but darker stripes down the neck. I thought perhaps the adolescents could have had a more patterned body, maybe so they're easier for adult herdmates to see, while the giant grown-ups lose this patterning and develop bolder face and throat markings for display.

Dinovember 2016, Day 13

Sauropods may have had noisy noses. 

Name: Daxiatitan binglingi
Meaning: titan of the Daxia [branch of the Yellow River] from Bingling Temple [famous site near where it was found]
Time: Early Cretaceous, c 122.6 million years ago
Place: northwestern China
Size: about 23 metres (75.5 feet) long and 20-25 tonnes (22-27.6 tons)
Type of Dinosaur: euhelopodid macronarian (very long-necked big nosed plant-eating dinosaur)

Despite initial claims of extreme size, Daxiatitan does not appear to be one of the largest dinosaurs of all time, attaining a size that, while certainly respectable, is not all that giant among the sauropods. It belonged to a derived group of sauropod dinosaurs with extremely long necks and long forelimbs that is so far only known from Asia.

In this picture, I imagined a male Daxiatitan, at back, courting a female by making a bellowing call and inflating colourful flaps of skin around his nose and along his neck. Both sexes have similar patterns though.

Dinovember 2016, Day 9

Sauropods relax and get cleaned up a bit, too.

Name: Patagosaurus faraisi
Meaning: [owner of the land where it was found, Ricardo] Farais's Patagonian reptile
Time: Middle Jurassic, c 165 million years ago
Place: Patagonia
Size: 15-16.5 metres (49-54 feet) long, 7.8-9.4 tonnes (8.6-10.4 tons)
Type of Dinosaur: cetiosaurid sauropod [primitive giant long-necked dinosaur]

Here, an adult and juvenile of the long-necked sauropod dinosaur Patagosaurus do something you don't see sauropods do often in palaeoart: sit down and relax. While resting by a tree on a hill, the giants are visited by little heterodontosaurs called Manidens - small, fuzzy omnivorous dinosaurs with beaks and procumbent tusks. I've imagined a scenario here that this is a sort of cleaning station where the large dinosaurs can come and rest while the small heterodontosaurs pick away parasites, flakes of sloughing skin and scales, and such.

Heck, let's give the little guys a profile too:

Name: Manidens condorensis
Meaning: hand-tooth from Cerro Cóndor [in reference to the shape of its back teeth and the village near its discovery site]
Time: Middle Jurassic, c 165 million years ago
Place: Patagonia
Size: 60-70 centimetres (23.6-27.6 inches) long
Type of Dinosaur: heterodontosaurid [tusked beaked dinosaur]

Technically, I may have fudged this one a bit. Manidens and Patagosaurus are from the same geologic formation but Manidens might be from a layer a couple of million years older than Patagosaurus. As far as I know, the dates for their formation are a bit uncertain so I'm not too concerned with drawing them as contemporaries. Certainly they would have had related animals coexisting if nothing else.

Dinovember 2016, Day 6

Barosaurus, small and large. Also, sauropods: it takes a special kind
of organism to make an individual the length of two buses 'small.'

Name: Barosaurus lentus
Meaning: slow heavy reptile
Time: Late Jurassic, c 150 million years ago
Place: South Dakota, Utah, Colorado
Size: about 25 metres (82 feet) long and 13 tonnes (14.3 tons) typically; some (presumably) very old individuals appear to have reached sizes of approximately 50 metres (164 feet) long and 105 tonnes (116 tons)
Type of Dinosaur: diplodocine diplodocid (slender-built whip-tailed long-necked dinosaur)

Barosaurus is often forgotten amongst the Morrison Formation sauropods, losing out to more famous and familiar contemporaries Diplodocus, Brontosaurus, Apatosaurus, Camarasaurus, and Brachiosaurus. The impressive rearing specimen at the American Museum of Natural History is probably Barosaurus's most iconic - which isn't bad at all; many would say the AMNH display is the most incredible fossil mount in the world. Other than that, though, Barosaurus just doesn't have the presence some of its neighbour sauropods do.

However, there's the 'little' matter of BYU 9024 to consider... this specimen, a neck vertebra, comes from the Dry Mesa Quarry in Colorado and, at 138 centimetres (54.3 inches) long, is the largest vertebra known from any animal, ever. Initially identified as coming from a Supersaurus specimen, the SV-POWsketeers Mike Taylor and Matt Wedel have recently proposed that this bone is from Barosaurus - it matches the existing specimens of Barosaurus perfectly, except in size. This bone would come from an animal roughly twice as long as the AMNH mount, and probably around eight times as massive. In the picture above, the animal in the foreground is an AMNH-style, 25-metre Barosaurus; the looming monstrosity in the background is a BYU-style, 50-metre individual... and I'm not actually sure that I made it big enough.

Day of the Diplodocids Redux

And he means business -- just check out that switchblade comb.
[by the author]

Remember Tschopp et al 2015? You know the paper... Brontosaurus is back! Huzzah and tally-ho and all that. I wrote about it here, nearly 15 months ago. I'm bringing it back up now because it will be relevant to a post that I've had in the works for a little while now. That should hopefully materialise here within the next little while but before it does, let's look back at good ol' Brontosaurus and see what was really important about its resurrection from the open grave of taxonomic obsolescence...

Day of the Diplodocids

Welcome, true believers, to a Very Special installment of Noah's Ravens. As you have no doubt seen while scrolling through Facebook or Twitter or while idly surfing the web, yesterday marked the appearance of a new (very long) paper reviewing the diplodocid sauropods, 'A specimen-level phylogenetic analysis and taxonomic revision of Diplodocidae (Dinosauria, Sauropoda)' by Emanuel Tschopp, Octávio Mateus, and Roger B J Benson, published open-access in PeerJ. Although I'm certain you've all had time to read it, pore lovingly over the cladograms, savour each and every word about each and every specimen, and completely lose yourself in the figures depicting small chunks of bone, I thought it might be nice to have a brief(ish) round-up post that covers some of the big ideas of the paper in a condensed(ish), hopefully-easy(ish) read.

It was nice knowing you, Diplodocus longus, but all good things
must come to an end. Read on to find out why. Legs belonging to
The Sauropod Formerly Known As Diplodocus longus at centre.
[photograph by the author]