Tag Archives: Triassic

Education, Geology, Paleontology, Science

Know Your Bones: March 2016

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Last month’s challenge went unguessed, meaning the final bragging rights for Know Your Bones belongs to me.

 

So, what is the name of the critter in last month’s challenge? It is Coelophysis bauri.

 

photo Dayatthemuseum082_zps3be8952d.jpg
(Taken at the New Mexico Museum of Natural History and Science)

 

Coelophysis bauri lived during the late Triassic 208 to 228 million years ago. Most specimens are found in New Mexico, however, several specimens of related species (specimens that would be classified as Coelophysis) have been found worldwide, dating to as late as the early Jurassic. Coelophysis is one of the earliest dinosaurs known to science and the earliest known from complete specimens. Coelophysis was ~3 meters in length and would have stood ~1 meter at the hip. Coelophysis is a theropod with sharp curved teeth. It possessed four fingers on its forelimbs, which is the basal trait for theropods. It is believed that Coelophysis was a fast and agile predator.

 

photo 2013-03-03091919_zpsaa913bc8.jpg
(Taken at the New Mexico Museum of Natural History and Science)

 

Coelophysis is one of the earliest dinosaurs discovered, being named by Edward Drinker Cope in 1889. Coelophysis means “hollow form,” because Cope noticed that it possessed hollow bones, something shared with all later theropods. Coelophysis also possessed a furcula (i.e. a wishbone) and a sclerodic ring seen in the orbit of the skull. The sclerodic ring allowed for muscle attachments which would have given Coelophysis amazing vision, much like modern birds of prey. As pointed out above, Coelophysis is one of the earliest dinosaurs and it already had all these traits that are found in modern birds. It would not be surprising to find out that Coelophysis also possessed feathers.

 

photo 2013-07-26113514_zpsc84222fd.jpg
(Taken at the New Mexico Museum of Natural History and Science)

 

Thank you for everyone that ever participated in this. I did enjoy it, but I feel my time is better spent blogging about a different subject.

Education, Geology, Paleontology, Science

Know Your Bones: December 2015

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Last month’s challenge brought out a few good guesses and two that were correct. However, like so many other times, only one person was the most correct. Last month that happened to be our resident paleontologist Isotelus with the more correct answer.

 

A phytosaur; I know there’s some reassigning going on, so Pseudopalatus/Machaeroprosopus? I don’t know species names, at least not for this genus.

 

This critter is indeed Machaeroprosopus buceros formally known as Pseudopalatus buceros. Red identified the wrong species name and I was unaware when I picked the critter that its genus had changed. Thus, Isotelus should get extra kudos. Honestly, I picked this obscure critter mainly so WarK would not get a third victory in a row.

 

photo 2015-11-13 10.17.46_zpssyixbclr.jpg

(Taken at the New Mexico Museum of Natural History and Science)

 

M. buceros lived during the late Triassic 205 million years ago and is found only in New Mexico. However, Machaeroprosopus species are found through out the southwest of the U.S. M. buceros grew to 3-4 meters as adults. M. buceros was an aquatic predator that would have lived its life much like a modern crocodilian, which is catching fish or ambushing prey at the shoreline. During the late Triassic, a giant swamp covered most of what is now the modern southwest of the U.S. Several different species of aquatic predator are found throughout this area and time range.

 

photo 2014-01-10095114_zps1f2ad95b.jpg

(Taken at the New Mexico Museum of Natural History and Science)

 

Even though it looked very similar to modern crocodilians, M. buceros was a phytosaur, which are only distantly related to crocodiles, making this a classic case of convergent evolution. One of the easiest ways to tell the difference between a crocodilian and a phytosaur is where the nasal aperture is located. On a phytosaur, the nasal aperture is located on the back of the head near the eyes, while a crocodilian’s nasal aperture is located on the tip of their snouts. The specimens of M. buceros show sexual dimorphism in the skulls. There is a robust morph believed to be male and a gracile morph believed to be female. This is mainly based on our observations of crocodilians and their sexual dimorphism in which the males are the larger of the two.

 

Moving on to next month’s challenge:

 

photo 2013-12-27110604_zps44be6f46.jpg

(Taken at the New Mexico Museum of Natural History and Science)

 

Good luck to everyone that plays.

Education, Geology, Paleontology, Science

Know Your Bones: June 2015

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Last month’s challenge was a stumper. For most of the month, only one person dared to give a guess. Nevertheless, it was not until days before the month ended that Isotelus came in with the correct answer.

 

The Dicynodont Placerias hesternus

 

This critter is indeed Placerias hesternus.

 

photo 2015-06-05 09.36.01_zps3si6xnjp.jpg

(Taken at the New Mexico Museum of Natural History and Science)

 

Placerias lived during the late Triassic 221 to 210 million years ago. Placerias would have reached a length of ~3.5 meters and weighed in at nearly 1000 kilograms, making it one of the largest herbivores known about during this time. It was also one of the most common animals around during the late Triassic. Placerias had a beak and two tusks, which are common traits for dicynodonts. Both males and females had the same size tusks, thus they would have most likely used them in obtaining food and defense; not necessarily in finding mates. It is thought that Placerias would have had a life style similar to modern hippopotamuses, wallowing in semi-shallow rivers and lakes and spending little time outside of water.

 

photo 2015-06-05 09.36.59_zps7guvthxk.jpg

(Taken at the New Mexico Museum of Natural History and Science)

 

Even though Placerias lived during the “Age of Dinosaurs” (the Mesozoic), it was not a dinosaur, it is a synapsid. Along with being a synapsid, it is also a therapsid, meaning it is very closely related to modern mammals, but falls outside of the modern mammal clade. Fossil animals, such as Placerias, are found across the world and were key evidence to help establish that at one time in earth’s past, all the continents were of one land mass (Pangaea). Dicynodonts are the second most successful synapsid clade and are only surpassed by mammals in their diversity and longevity.

 

Moving on to next month’s challenge:

 

photo Dayatthemuseum036_zpsb8b3d5b6.jpg

(Taken at the New Mexico Museum of Natural History and Science)

 

Since last month’s was so difficult, I am hoping this one is much easier.

Education, Geology, Paleontology, Science

Know Your Bones: August 2014

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Last month’s challenge brought in a few good guesses, but only one correct answer. Once again, Isotelus guessed correctly, and within hours of the posting of the challenge.

 

 While it looks like a Wiener dog T-rex, I’m going to guess: 

 

This prehistoric wiener-dog is indeed Postosuchus.

 

(Taken at the Dinosaur Museum and National Science Laboratory)

 

During the late Triassic (288 to 202 million years ago), Postosuchus roamed across most of what is now North America. During this time, it was one of the largest predators on earth. It could have hunted and killed any of the dinosaurs that were alive at the same time. Postosuchus could reach a length of ~4 meters, stood ~2 meters tall, and could have weighed 250 to 300 kilograms. Postosuchus possessed a skull that was 55 cm long and 21 cm across.

 

Postosuchus had protective plates that covered their back, neck, and tail. These plates are something they share with their closest living relative the crocodilians. However, Postosuchus was a terrestrial predator and walked with its legs directly under the body. This armor probably protected them from other Postosuchus. During the late Triassic, there were not many other critters in the world that could challenge a full-grown and healthy Postosuchus, except another Postosuchus.

 

Moving on to this month’s challenge:

 

 

(Taken at the New Mexico Museum of Natural History and Science)

 

Good luck and thanks to everyone that reads and guesses.