Image courtesy of Raul Martin
Palaeontologists
can’t agree on whether fossils from several small dinosaurs represent juvenile
Tyrannosaurus rex or smaller adults of a separate species that lived alongside
them
Some researchers
think that Tyrannosaurus rex may not have been the only large carnivore
reigning over North America during the Late Cretaceous ,
A reinterpretation
of several fossils of small dinosaurs sometimes categorised as young T.
rex adds weight to the controversial idea that another smaller species,
called Nanotyrannus lancensis, lived alongside the king of the dinosaurs.
“This is the most
famous fossil animal in the world,” says Nicholas Longrich at the
University of Bath in the UK. “There are a lot of people looking at it. And we
can’t agree.”
“The debate
has divided palaeontologists for decades. A 1960s paper argued that a
skull unearthed two decades earlier in Montana’s Hell Creek Formation was from
a T. rex that had died before reaching full maturity. But in the
1980s, others argued that differences between the skull and known T.
rex specimens showed this fossil was in fact an adult of a distinct
species, which they named Nanotyrannus lancensis.”
Some researchers
have stated that the number of dinosaurs is smaller than what is sad in journals.
More recent work
based on additional fossils disputed this, arguing that the variation between
the smaller fossils and full-size T. rex fossils were
differences of age, not of species. The debate has implications for making
sense of the ecology and diversity of dinosaurs in the period just before they
went extinct.
Source:
James Dinneen, 2024. Tiny T. rex fossils may be distinct
species – but not everyone agrees | New Scientist. 3 January
Posts
