Lightnews — Scholar-powered news

Dr Suresh Singh

@palaeosingh.bsky.social

1.5K followers 530 following 310 posts

• Vertebrate Palaeontologist •📍The Open University, UK • Interested in understanding the links between morphology, ecology & evolution through deep time, with a focus on terrestrial tetrapods & ecosystems • 🌿- 🦕- 🦖

Posts Media Videos Starter Packs

Pinned

Dr Suresh Singh @palaeosingh.bsky.social · Aug 16

For #FossilFriday, I thought I’d share my paper published earlier this year on the #macroevolution of carnivorous non-mammalian synapsids: www.nature.com/articles/s42...

May be of interest if you’re curious about the feeding morphology & ecology of Permian predators like Inostrancevia & Dimetrodon

Title & abstract of the scientific paper, “Predatory synapsid ecomorphology signals growing dynamism of late Palaeozoic terrestrial ecosystems” by Singh et al. 2024

A skeleton of the late Permian gorgonopsid, Inostrancevia on display at the Royal Ontario Museum in Toronto.

A pair of early Permian, basal ‘pelycosaur’ synapsid skeletons on display at the Field Museum in Chicago.

7 22

Reposted by Dr Suresh Singh

Steve Brusatte @stevebrusatte.bsky.social · 2d

On this #fossilfriday, take a few moments to read this.

A touching tribute to the life, career, and discoveries of Mark Norell, from his long-time friend and field companion, Mike Novacek. In @nature.com

www.nature.com/articles/d41...

Mark Norell obituary: palaeontologist who showed that dinosaurs still walk among us — as birds

Through fieldwork and innovative research, he transformed how scientists and the public perceive the prehistoric world.

www.nature.com

9 34

Dr Suresh Singh @palaeosingh.bsky.social · 2d

It’s surprisingly large & robust, almost like a banana in shape. Quite tyrannosaur-like

Dr Suresh Singh @palaeosingh.bsky.social · 2d

Though large & packing a formidable set of jaws, #erythrosuchids did not retain their position as top predators for too long, declining & being superseded by more upright & cursorial #archosaurs, such as pseudosuchian paracrocodylomorphs, through the Middle #Triassic.

🧵 End.

Dr Suresh Singh @palaeosingh.bsky.social · 2d

However, unlike theropod dinosaurs, erythrosuchids were not thought to be speedy or agile, as they possessed slightly sprawling, semi-erect limbs. They were slower & less efficient moving around. As such, erythrosuchids were probably ambush predators.

5/

1 1

Dr Suresh Singh @palaeosingh.bsky.social · 2d

The skull is very reminiscent of those of large #theropod dinosaurs from much later in the #Mesozoic, with thick, conical teeth similar to those of #tyrannosaurs 🦖 - Erythrosuchus likely employed similarly powerful, crushing bites to quickly debilitate its prey.

4/

1 1

Dr Suresh Singh @palaeosingh.bsky.social · 2d

#Erythrosuchus was also notable for possessing an unusually large head for its size, with a skull that reached up to 1 metre in length. You can get a sense of its scale from the photo - that’s my hand holding just the tip of the snout! Its large head housed a very powerful set of jaws.

3/

1 1

Dr Suresh Singh @palaeosingh.bsky.social · 2d

Reaching up to 5 metres long, #Erythrosuchus was one of the first, really big terrestrial predators to emerge on land in the Triassic after the End-Permian mass extinction event (~251.9 MYA). It filled a top predator niche that had been previously occupied by #therapsids in the #Permian.

2/

1 1

Dr Suresh Singh @palaeosingh.bsky.social · 2d

A couple snapshots of an ancient apex predator for this #FossilFriday - presenting the fossil teeth & snout of an #Erythrosuchus africanus, the big-headed, hypercarnivorous archosauromorph from the Early-Mid #Triassic of South Africa 🇿🇦

#Paleontology #Science

🧵 1/

Isolated teeth of Erythrosuchus africanus from the collections of the Natural History Museum UK.

The tip of the snout of Erythrosuchus africanus from the collections of the Natural History Museum UK.

2 13 29

Reposted by Dr Suresh Singh

Thomas R. Holtz, Jr. @arctomet.bsky.social · 2d

Animated Scutellosaurus!! (Also Dilophosaurus, prosauropods, and dimorphodonts, but I think I've seen animations of all those before...)

youtu.be/BYCjeNQvISM?...

"Hunted by Moonlight" | Dinosauria Series | Animated Teaser

YouTube video by Dead Sound

youtu.be

2 14 39

Reposted by Dr Suresh Singh

Thomas R. Holtz, Jr. @arctomet.bsky.social · 9d

For #FossilFriday, in honor of the 120th naming of both species (tomorrow), the type specimens of Tyrannosaurus rex (at the Carnegie Museum) and Albertosaurus sarcophagus (@museumofnature)

Fossil partial skull of Albertosaurus sarcophagus

2 32 120

Dr Suresh Singh @palaeosingh.bsky.social · 9d

Its discovery shed new light on the evolution of hyper-specialised, megapredatory tyrannosaurids 🦖 Lythronax captures the early evolution of the Tyrannosaurus-style predatory ecology ~20 million years before T. rex.

🧵 End.

1 5

Dr Suresh Singh @palaeosingh.bsky.social · 9d

Reinforced skulls would have allowed these predators to withstand the high biomechanical stresses incurred from inflicting powerful bites on large, robust, struggling prey. These were megapredators, specialised to take on large prey.

5/

1 2

Dr Suresh Singh @palaeosingh.bsky.social · 9d

The positioning of the eyes provided better depth perception, allowing Lythronax, Tyrannosaurus, and Tarbosaurus to properly focus on their prey at both long & short distances, also enabling them to precisely time their attack/bite for maximum impact.

4/

1 2

Dr Suresh Singh @palaeosingh.bsky.social · 9d

The skull is short & similarly reinforced to T. rex & its close Asian relative, #Tarbosaurus. Additionally, #Lythronax has eyes that face forward more so than other tyrannosaurids, bar #Tyrannosaurus & Tarbosaurus. These were active predators adapted for rough interactions with prey.

3/

1 2

Dr Suresh Singh @palaeosingh.bsky.social · 9d

While smaller than T. rex at upto 5-8 metres long, #Lythronax is still thought to have been a similarly formidable ‘big game hunter’ of its time. Indeed, its skull anatomy appears to show its close evolutionary relationship & ecological similarity to T. rex.

2/

1 2

Dr Suresh Singh @palaeosingh.bsky.social · 9d

Here’s a snapshot of the basal tyrannosaurid, Lythronax argestes for this #FossilFriday. It lived ~80 Ma, making it a much older cousin of the famous, #Tyrannosaurus rex 🦖- Discovered in Southern Utah 🇺🇸, its name means "gore king from the southwest."

#Paleontology #Science #Dinosaurs

🧵 1/

A mounted reconstructed skeleton of the tyrannosaurid, Lythronax argestes, and its skull on display at the Utah Museum of Natural History in Salt Lake City, Utah, USA.

1 11 37

Dr Suresh Singh @palaeosingh.bsky.social · 11d

New paper by Degrange et al. reports a new phorusrhacid (AKA #TerrorBird) from La Venta, Colombia 🇨🇴 - this is the 2nd terror bird from the site, suggesting perhaps some niche partitioning between these giant avian predators ⬇️

#Paleontology #Science

www.mdpi.com/1424-2818/17...

Figure 1 from the paper, showing the locality location and geology.

Dr Suresh Singh @palaeosingh.bsky.social · 12d

New paper by Niedźwiedzki et al. reports ichnofossil 👣🐾 assemblage apparently made by ornithischian & megatheropod #dinosaurs in the latest #Triassic. Lots of interesting new info on the early rise of dinosaurs coming out of Poland! 🇵🇱 ⬇️

#Paleontology #Science

www.sciencedirect.com/science/arti...

An ornithischian-theropod ichnoassemblage from the Norian-Rhaetian transition of Poland

In this paper, we describe a dinosaur track assemblage from an Upper Triassic fluvial succession at the Lisowice-Lipie Śląskie site in Silesia, southe…

www.sciencedirect.com

4 16

Dr Suresh Singh @palaeosingh.bsky.social · 16d

This shows the challenges of trying to reconstruct the ecology of long extinct creatures! Whatever it did, Ceratosaurus was a highly successful predator - its fossils are reported from North & South America, Africa & Europe, and span ~155 - 143 Ma across the Late Jurassic.

🧵 End.

Dr Suresh Singh @palaeosingh.bsky.social · 16d

However, we have to be careful as while these palaeoenvironments could reflect the actual habitat preferences of Ceratosaurus, it could just be where their remains were preferentially preserved - such watery environments have better #fossil preservation potential.

6/

1 1

Dr Suresh Singh @palaeosingh.bsky.social · 16d

However, the long, blade-like teeth of Ceratosaurus have also been suggested as adaptations for feeding on fish 🐟 Further evidence for piscivorous diets comes from the palaeoenvironments these theropods are often found in - wetter environments with large bodies of water.

5/

Dr Suresh Singh @palaeosingh.bsky.social · 16d

Such klepto-parasitism is quite common among diverse predator communities - just think of mammalian predators of the African savannahs today. Larger carnivores will take their chances to steal a meal from smaller predators - much easier than hunting for themselves!

4/

1 1

Dr Suresh Singh @palaeosingh.bsky.social · 16d

However, these teeth were also more fragile, and ill-suited for biting into bone. Consequently, Ceratosaurus likely fed on the fleshiest parts of its prey, with its blade-like teeth helping to quickly slice off strips of meat before larger predators arrived to steal the kill.

3/

Dr Suresh Singh @palaeosingh.bsky.social · 16d

Ceratosaurus is a more primitive #theropod than its Morrison competitors (e.g., #Allosaurus & #Torvosaurus) but appears to have found a distinct niche within the carnivore guild. Its teeth were relatively long & thin, making them extremely effective at slicing off flesh 🔪

2/

1 1

Dr Suresh Singh @palaeosingh.bsky.social · 16d

Presenting the skull of #Ceratosaurus nasicornis for this #FossilFriday. This medium-sized (up to ~5.5 metres long), theropod dinosaur 🦖 was one of the rarer & perhaps most enigmatic predators of the #Jurassic Morrison Formation in the southwestern US 🇺🇸

#Paleontology #Science

🧵 1/

A skull reconstruction of Ceratosaurus nasicornis on display at the Brigham Young University Museum in Provo, Utah, USA. This skull was created using two fragmentary skulls in the museum’s fossil collections.

1 16 29