[GUEST ACCESS MODE: Data is scrambled or limited to provide examples. Make requests using your API key to unlock full data. Check https://lunarcrush.ai/auth for authentication information.]

@JGN_Paleo "I won't go into the background of the debate here - it's much too long Suffice it to say paleontologists have argued for decades about whether Nanotyrannus is a real dinosaur or not - and the debate has often been acrimonious"
X Link @JGN_Paleo 2025-10-30T16:00Z 4166 followers, 37.4K engagements

"But today in our new paper Dr. Lindsay Zanno and I have shown that science got this one wrong. Nanotyrannus was not the juvenile form of T. rex - it was its own species of sleek speedy predator that lived alongside T. rex at the twilight of the Age of Dinosaurs"
X Link @JGN_Paleo 2025-10-30T16:00Z 4166 followers, 38.5K engagements

"It's real. And it's spectacular. Sometimes one fossil really can change everything you think you know. NEW PAPER (see bottom of thread) AND 🧵"
X Link @JGN_Paleo 2025-10-30T16:00Z 4166 followers, 559.8K engagements

".and Lindsay and I showed that the last one was also flawed. T. rex and Nano both have very wide skulls but the "width" is not directly comparable. In T. rex the skull is very wide and is over 1/2 the length of the skull. In Nano the skull width is less than 1/2 its length"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 18.5K engagements

"The Dueling Dinosaurs are a pair of exceptionally preserved dinosaurs - a Triceratops and as we now know a Nanotyrannus. The Nano is spectacularly complete - XXX% complete. Every bone of its body is present - and those bones brought new data to an old debate"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 415K engagements

"We think Nanotyrannus still used its hands for hunting at least a little. But they do show a sign of the evolutionary arm reduction that defined other tyrannosaur species - a vestigial third finger represented only by a single finger bone"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 36.1K engagements

"Before I end I want to give a shoutout to the amazing scientist who made all of this possible. Thank you so much Lindsay for everything. I learned so much about being a scientist while I worked in your lab - lessons I'll never forget and I hope to teach to students of my own"
X Link @JGN_Paleo 2025-10-30T16:02Z 4166 followers, 11.9K engagements

"As a proud out-of-touch East Coaster I would love for Nanotyrannus to have originated here. But we need to do a lot more science to know for sure - and wait for the discovery of better fossils of East Coast dinosaurs"
X Link @JGN_Paleo 2025-10-30T16:02Z 4166 followers, 11.2K engagements

"Regardless of these lingering questions the recognition of a valid Nanotyrannus means we need to rethink a lot of what we "know" about T. rex and its kin. We need to re-evaluate every species describe more fossils and re-do all of the studies that assumed Nano was invalid"
X Link @JGN_Paleo 2025-10-30T16:02Z 4166 followers, 13.7K engagements

"But the consensus was until today that these small theropod dinosaurs are T. rex teenagers. And this has become a foundational assumption in many many studies on T. rex and how it lived evolved and grew"
X Link @JGN_Paleo 2025-10-30T16:00Z 4166 followers, 37.3K engagements

"How did we prove it The right combination of an exceptional new fossil - the Dueling Dinosaurs tyrannosaur - and laser-focused science using multiple lines of evidence to test different hypotheses and lead us to the truth"
X Link @JGN_Paleo 2025-10-30T16:00Z 4166 followers, 37K engagements

"Nanotyrannus also has way more teeth in its jaws - up to XX in the DD skull and as few as XX. T. rex never has more than XX teeth. Despite many claims to the contrary tyrannosaurs do not lose teeth as they grow"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 28.4K engagements

"In 1999 Thomas Carr justified tyrannosaur tooth loss with crocodylians which he said lost teeth during growth too. But they don't. My own work on alligators found no evidence of growth-related tooth loss and the studies Carr cited actually don't support his claim"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 22.2K engagements

"If it did it would be evidence that they were either the same species or very close relatives. Carr (1999) had said that there were XX of these traits but Currie (2003) showed that XX of these were actually not unique to T. rex and Nanotyrannus"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 18K engagements

"One of our analyses painted an even more intriguing idea - that Nanotyrannus had its ancestry in the Eastern half of North America and migrated into T. rex's territory as sea level fell and reconnected the two halves of the continent. But we can't yet test this idea further"
X Link @JGN_Paleo 2025-10-30T16:02Z 4166 followers, 24.3K engagements

"For paleontologists and dinofans Nanotyrannus needs no introduction. This unassuming little skull is the unlikely focus of the most infamous debate in paleontology. Is it its own species Or is it a young T. rex It seems like a simple question - but its been very hard to solve"
X Link @JGN_Paleo 2025-10-30T16:00Z 4166 followers, 42.6K engagements

"For one its hands The hands of Nanotyrannus had never been discovered before the DD Nano. They're huge Some bones are twice as long as the same bones in T. rex. The claws are enormous and hooked and the finger bones have well-developed muscle attachment sites"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 44.5K engagements

"T. rex famously only had two fingers but Nanotyrannus technically still had three. Bones don't shrink or vanish during growth - so the huge hands and "bonus" finger of the DD Nano showed us clearly that the animal couldn't be a young T. rex"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 29.4K engagements

".which would need to vanish during growth if it's T. rex. If anything sinuses get bigger during growth And my PhD work on living crocodylians showed that presence or absence of sinuses in particular bones is useful for species identification even for tiny hatchlings"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 26.1K engagements

"They're talking about a very particular circumstance where overgrowth of a tooth from the lower jaw erodes away and destroys the socket for a tooth at the tip of the snout. It's common - but it's not a seamless reduction in the number of teeth"
X Link @JGN_Paleo 2025-10-30T16:01Z 4166 followers, 22K engagements

"We created a new phylogenetic data matrix to figure out the interrelationships of tyrannosaurs and found that Nanotyrannus is a member of a very early-diverging group of tyrannosaurs"
X Link @JGN_Paleo 2025-10-30T16:02Z 4166 followers, 27.5K engagements

"If it weren't for Lindsay's hard work grit and determination the Dueling Dinosaurs may never have made it to a museum collection. Our field owes her and everyone who worked with her to bring these specimens into the public trust a debt of gratitude"
X Link @JGN_Paleo 2025-10-30T16:02Z 4166 followers, 93.7K engagements

"@FossilLocator The study found that Jane was still growing when she died. We agree with their assessment - but disagree that it makes her a juvenile T. rex. The anatomy is clearly Nanotyrannus but with enough differences that we consider this specimen to be a different species"
X Link @JGN_Paleo 2025-10-30T18:13Z 4150 followers, 1538 engagements

"@SouthApe I think they would have been much more similar to adults than weve generally thought. Think the difference between young and adult Gorgosaurus. But research is ongoing"
X Link @JGN_Paleo 2025-11-01T13:35Z 4164 followers, XXX engagements