Page 28 - ARUBA TODAY

A28 SCIENCE
Thursday 23 March 2017

New idea shakes up dinosaur family tree for T. Rex and pals

SETH BORENSTEIN narios, he said.
AP Science Writer It may sound like an aca-
(AP) — Tyrannosaurus Rex demic exercise, but it’s im-
and his buddies could be portant to understand how
on the move as a new big animals changed with
study proposes a massive time, said Baron said, not-
shake-up of the dinosaur ing that the dinosaurs ruled
family tree. Earth for more than 150 mil-
Scientists who took a lion years.
deeper look at dinosaur His research suggests that
fossils suggest a different dinosaurs popped up 247
evolutionary history for di- million years ago — 10
nosaurs, moving theropods million years earlier than
such as T. Rex to a new the standard theory says
branch of the family tree — with a dinosaur from
and hinting at an earlier Tanzania in East Africa. It’s
and more northern origin called Nyasasaurus , was 6
for dinosaurs. to 10 feet tall and a plant-
The revised dinosaur tree eater.
makes more sense than He also found an animal
the old one, initially de- that’s not quite a dino-
signed more than a cen- saur, but as close as you
tury ago based on hip can get, that is a reptil-
shape, said Matt Baron, ian ancestor. And it was in
a paleontology doctoral Scotland. Previous theories
student at the University pointed to dinosaurs first
of Cambridge in England. evolving out of the South-
He is the lead author of the In this April 15, 2014 file photo, a cast of a Tyrannosaurus rex discovered in Montana greets visitors ern Hemisphere and many
study in Wednesday’s jour- as they enter the Smithsonian Museum of Natural History in Washington. outside scientists said there
nal Nature. Associated Press wasn’t enough evidence
“If the authors are correct, to support Baron’s northern
this really turns our long- ta who wasn’t part of the THISS’-kee-a). It includes that we’ve always thought concept.
standing understanding of study, wrote in an email. the stegosaurus. The group were very closely related to The paper is already di-
dinosaur evolution upside Dinosaurs are split into with reptile-like hips is each other might not be,” viding dinosaur experts.
down!” Kristi Curry Rogers, two groups. One group called Saurischia (saw-RIS’- said Rogers, who praised Famed dinosaur expert
a paleontologist at Maca- has bird-like hips and is kee-a), and includes the the study, saying it prompts Paul Sereno at University
laster College in Minneso- called Ornithischia (or-ni- brontosaurus. a whole bunch of new of Chicago called the ba-
Theropods, which include questions. sis of the Baron family tree
T. Rex and the type of di- Baron and colleagues “weak” and said “the cen-
nosaurs that later evolved looked at 450 character- tral question the paper
into modern day birds, istics of 75 dinosaur spe- leaves unanswered for me
were considered an off- cies. They used computer is Why?”
shoot from the group that simulations to try to group Matthew Carrano, dino-
includes the brontosaurus. together those with similar saur curator at the Smith-
The new study moves them characteristics, creating sonian Natural History Mu-
to the group that includes tens of thousands of poten- seum, said it’s hard to side
the stegosaurus, but on a tial dinosaur family trees. with any theory because
different branch. The proposed one com- early dinosaur fossil records
“It means that animals bines the 80 most likely sce- are so incomplete.q