All articles tagged with #tyrannosaurus
Paleontologists say Tyrannosaurus rex evolved a massive skull and powerhouse bite to subdue prey, while its forelimbs were reduced because they offered little advantage as the predator grew—an energy-and-structure trade-off that left the arms vestigial, with possible minor roles but never matching the bite’s power.
A study published in the Proceedings of the Royal Society B analyzed 85 dinosaur species and found that tiny arms in T. rex and other giant carnivores are an evolutionary trade-off for increasingly large skulls; as skull strength rose to deliver more bite power, forelimbs shrank across multiple lineages around the world over roughly 180 million years, though their exact function remains unclear.
New research argues Tyrannosaurus and related theropods reduced forelimb size as they evolved larger, more robust skulls and jaws, using jaws as the primary weapon against enormous prey. An analysis of 61 theropods shows a strong link between short arms and robust skulls across five families, with skull growth likely preceding arm reduction. Forelimbs retained some function but did not drive the arms’ evolution; the study emphasizes correlation, not direct causation, and was published in Proceedings of the Royal Society B.
A 75-million-year-old tyrannosaur foot bone bears 16 bite marks analyzed with 3D scanning and digital modeling, showing a smaller tyrannosaur fed on the larger relative. The study, led by Josephine Nielsen and published in Evolving Earth, suggests tyrannosaurs were opportunistic scavengers and even cannibalistic under certain conditions, challenging the long-held view of them as sole apex predators.
Researchers using synchrotron X-rays found preserved, iron-rich blood vessel structures in a fractured rib of Scotty, the largest-known Tyrannosaurus rex. The vessels illuminate the healing process from 66 million years ago and offer new insight into dinosaur biology, even as dinosaur DNA remains out of reach.
Paleontologists describe a nearly complete Edmontosaurus skull with a Tyrannosaurus tooth embedded in its snout and bite marks suggesting a fatal, close-range encounter. CT analysis indicates the tooth broke off during the attack, with the Edmontosaurus unlikely to survive; size estimates point to an adult T. rex with about a 1-meter-long skull. The find provides rare direct fossil evidence of predation and feeding behavior in large theropods, showing T. rex likely hunted and scavenged during its life.
A New Mexico shinbone dating to 74–75 million years ago may belong to an ancestor of Tyrannosaurus rex. Initially identified as Bistahieversor, the bone was reclassified toward Tyrannosaurus, suggesting early tyrannosaur evolution in NM, though more evidence is needed.
In 2025, paleontologists discovered several new dinosaur species, including a potential missing link in the Tyrannosaurus family tree called Khankhuuluu mongoliensis, a spiky dinosaur with long bones, a megaraptor named Joaquinraptor with preserved diet, and a dome-headed pachycephalosaur in Montana, revealing new insights into dinosaur evolution and diversity.
A recent study provides evidence that Nanotyrannus is a distinct genus from Tyrannosaurus, with two species coexisting in North America during the late Cretaceous, challenging previous assumptions about tyrannosaur ontogeny and diversity.
An international team of paleontologists discovered a new dinosaur species called Khankhuuluu, considered the closest ancestor of Tyrannosaurs, living about 86 million years ago in Mongolia. The find sheds light on Tyrannosaur evolution, migration from Asia to North America, and the development of their predatory traits, with plans for further research into their ancestors.
Scientists have identified a new species of Tyrannosaurs, T. mcraeensis, which is believed to be the closest relative to T. rex. This discovery suggests that Tyrannosaurs grew to enormous sizes much earlier than previously thought, shedding light on the origins of T. rex in North America rather than Asia. The fossils, originally thought to belong to T. rex, were found in New Mexico and are estimated to have lived 6-7 million years before T. rex existed. The new species had key differences from T. rex, indicating it as a distinct species. This finding challenges previous assumptions about the evolution and origins of T. rex.
Scientists have re-evaluated a partial skull found in New Mexico in 1983 and concluded that it represents a new species of Tyrannosaurus, called Tyrannosaurus mcraeensis, predating the famous T. rex. They observed subtle differences from T. rex in the skull, leading to the recognition of a separate species. However, some researchers doubt this conclusion, citing unremarkable differences and problematic dating. The discovery challenges the understanding of Tyrannosaurus origins and suggests that giant species of this group evolved earlier than previously thought.
Researchers have identified a new species of Tyrannosaurus, T. mcraeensis, as the closest known relative of the T. rex, challenging previous theories about the dinosaur's origins. The discovery, based on fossils found in southern New Mexico, suggests that the T. rex may have originated in North America millions of years earlier than previously believed. However, some experts are skeptical of the findings and further study is needed to determine the distinctiveness of the new species.
Researchers have discovered a new species of Tyrannosaurus, named Tyrannosaurus mcraeensis, in New Mexico, which predates the familiar T. rex by 5 to 7 million years. The fossil, initially thought to belong to T. rex, exhibits distinct differences in skull structure and teeth. The discovery suggests a new origin story for the iconic dinosaur, indicating that the McRae Formation in New Mexico is older than previously thought. This finding challenges the traditional timeline of T. rex evolution and provides new insights into the early evolution of this famous predator.
A tyrannosaurus fossil has provided scientists with new insights into the carnivore's diet. The fossil of a gorgosaurus libratus, part of the tyrannosaurid group that includes the T. rex, contained the preserved hind limbs of two yearling caenagnathid dinosaurs inside its abdominal cavity. This discovery suggests that young tyrannosaurids may have hunted small dinosaurs until they grew bigger and began to feed on larger prey. The findings also indicate that tyrannosaurids played both mesopredator and apex predator roles in their lifetime, contributing to their evolutionary success.