From Newsgroup: sci.bio.paleontology

I have doubts that Dinos bashed heads like goats do...

but anyway

https://www.nytimes.com/2026/01/27/science/raptor-fossil-dinosaur-skull.html

TRILOBITES

You WouldnrCOt Want to Butt Heads With This Small Dinosaur
A newly discovered raptor had a knobby bump on its head, suggesting
that, like some larger dinosaurs, it engaged in competitive head bashing.

N++
Listen to this article -+ 4:26 min Learn more
N++Share full article
N++
N++N++32
N++
An artistrCOs interpretation of Xenovenator espinosai, a newly discovered species of cassowary-size, head-butting raptor from Mexico that lived
during the Late Cretaceous period.Credit...Andy Fraser
By Jack Tamisiea
Jan. 27, 2026
Head-butting was all the rage at the end of the dinosaursrCO reign.

During the Late Cretaceous period, several dinosaur lineages evolved
dangerous headgear, including the dome-headed pachycephalosaur and the Pachyrhinosaurus, a horned dinosaur that sported a stump of gnarled bone
on its face.

Other dinosaur groups, including birdlike theropods, appear to have
avoided bashing one another head-on. But a newly discovered species of cassowary-size raptor from Mexico reveals that some of these
featherweights may well have been more than capable of cracking skulls.

A team of paleontologists recently described a set of thick bones on top
of the dinosaurrCOs braincase that fused together into a knobby bump. The scientists proposed that the new dinosaur, named Xenovenator (or
rCLstrange hunterrCY) espinosai, used the structure to ram into rivals.
Their report was published this month in the journal Diversity.

rCLRaptorlike dinosaurs are often imagined primarily as agile predators
using their claws and teeth,rCY said H|-ctor Rivera-Sylva, a paleontologist
at the Museo del Desierto in Saltillo, Mexico, and the lead author of
the paper. rCLXenovenator reminds us that dinosaur behavior was likely far
more diverse and nuanced.rCY

ADVERTISEMENT

SKIP ADVERTISEMENT
N++
In 2000, Martha Aguill||n-Martinez, one of Dr. Rivera-SylvarCOs colleagues
and co-authors, discovered XenovenatorrCOs fossilized braincase eroding
out of the ground while she was surveying the Cerro del Pueblo
formation, an outcrop of rocks in northeastern Mexico. Some 73 million
years ago, this area was a marshy coastline inhabited by several
dinosaurs, including duck-billed herbivores, lanky tyrannosaurs and Coahuilaceratops, which sported four-foot-long horns.

The researchers concluded that the fossilized braincase represented a troodontid, from a group of omnivorous, birdlike dinosaurs that had
large, forward-facing eyes and possessed some of the biggest brains of
any nonavian dinosaurs.

However, not all scientists are convinced that Xenovenator was a
troodontid. rCLItrCOs such a weird specimen,rCY said David Varricchio, a paleontologist at Montana State University who was not involved in the
new paper. Because the braincase was isolated, he said, he thinks it is possible that it could belong to the skull of a larger dinosaur. rCLIt
looks big brained because this is all we have, but maybe it was part of
a massive skull.rCY

EditorsrCO Picks
N++
This Sheet-Pan Shrimp and Rice Is Extremely Nice
N++
These A.I. Dreamers DonrCOt Fit the Stereotype
N++
10 New Movies Our Critics Are Talking About This Week
SKIP ADVERTISEMENT
N++
N++
N++
Preparing the fossilized braincase for a close-up under the microscope
at the Museo del Desierto in Mexico. The braincase contained dense bones
that fused together to form a knobby bump. Credit...Lucia Alfaro
Accounting for the confusion is the odd shape of the new braincase,
which has a bulge of wrinkled bone at the front. To peer inside the
petrified noggin, the scientists did a CT scan of the fossil. They
discovered that the bones, which fused together in zigzag patterns, were
nearly half an inch thick in spots and exhibited a spongy internal
structure.

ADVERTISEMENT

SKIP ADVERTISEMENT
N++
Because the reinforced skull probably did not help Xenovenator hunt, the researchers have theorized that the structure was a sexually-selected
trait used to bludgeon rivals. rCLFossils rarely preserve behavior
directly, so finding such strong morphological signals of combat in a small-bodied theropod was unexpected,rCY Dr. Rivera-Sylva said.

The bony bump on XenovenatorrCOs head resembles structures seen in several other head bashers, past and present. In addition to resembling the pachycephalosaurrCOs dense dome, the raptorrCOs fused skull bones are
similar to those seen in buffalo, musk oxen and giraffes. And the spongy structure inside XenovenatorrCOs bones also resembles the shock-absorbing tissue inside the bony casques of helmeted hornbills, which ram into
each other in midair.

Dr. Rivera-Sylva is not surprised that these big-brained raptors
competed for resources. Dr. Varricchio also thinks it is likely that troodontids tussled with one another. For example, his team has
discovered that troodontids often returned to the same sites to lay
their eggs, which may have caused conflicts over prime nesting spots.

Competition increased during the Late Cretaceous period, when a diverse assemblage of dinosaurs crowded ecosystems. Some developed deadly
weapons to duke it out with rivals, while others evolved showy horns and
fleshy crests to woo mates.

This made Xenovenator a creature of its time. rCLRather than being an
anomaly, Xenovenator fits into a broader pattern,rCY Dr. Rivera-Sylva
said. rCLDinosaurs at the end of the Cretaceous were not just evolving new
ways to eat or move, but new ways to interact with one another.rCY

A version of this article appears in print on Feb. 3, 2026, Section D,
Page 2 of the New York edition with the headline: Skull Crackers: In a Competitive Ecosystem, This Dinosaur Used Its Head. Order Reprints |
TodayrCOs Paper | Subscribe
--- Synchronet 3.21b-Linux NewsLink 1.2