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The fossil skull of a wrinkle-faced, meat-eating dinosaur whose cousins
lived as far away as South America and India has emerged from the
African Sahara, discovered by a team led by University of Chicago
paleontologist Paul Sereno. The find provides fresh information about
how and when the ancient southern continents of Africa, South America
and India separated.
The new species, which is 95 million years old, and a second new
meat-eating species Sereno found on a separate expedition, help fill in
critical gaps in the evolution of carnivorous dinosaurs on Africa. The
species are described in a paper published online June 2 in the
Proceedings of the Royal Society of London, Biological Sciences. The
July issue of National Geographic magazine also will include an article
on one of the dinosaurs. Sereno’s research was funded by National
Geographic, the David and Lucile Packard Foundation, the Pritzker
Foundation and Nathan Myhrvold.
Sereno, a National Geographic Explorer-in-Residence, has named the
ancient skull Rugops primus, meaning “first wrinkle face.” Measuring
about 30 feet long in life, the animal had a short, round snout and
small, delicate teeth, he said. It belongs to a group of southern
carnivorous dinosaurs called abelisaurids.
The head of Rugops had a tough covering of scales or surface armor
and was riddled with arteries and veins, leaving a crisscross of
grooves on the skull. “It’s not the kind of head designed for fighting
or bone-crushing,” Sereno said. Instead, he believes Rugops was a
scavenger, using its head to pick at carrion rather than fighting other
animals for food.
Sereno is puzzled by the presence of two neat rows of seven holes
along the dinosaur’s snout. He speculates that the holes anchored
something ornamental, used by the animal for display. “This may have
been a scavenger with head gear,” he said. “It’s really a beautiful
intermediate species of the group that later evolved into the first
The authors of the scientific paper describing the two new dinosaur
finds are Sereno, Jeffrey Wilson of the University of Michigan and Jack
Conrad of the University of Chicago. The second new dinosaur species,
named Spinostropheus gautieri, was found in Niger in the same
135-million-year-old rocks where Sereno’s expeditions excavated the
dinosaurs Jobaria and Afrovenator. The fossil is an articulated, or
connected, spine of a dinosaur and represents an ancient relative of
Rugops and other abelisaurids.
These finds provide fresh evidence about when Africa, Madagascar,
South America and India finally split from each other as a result of
continental drift. Before these discoveries, abelisaurids were
virtually unknown on Africa, leading some to suggest that Africa had
split off first from the southern landmass Gondwana, perhaps as early
as 120 million years ago. The new fossils indicate that Africa and
other southern continents that formed Gondwana separated and drifted
apart over a narrow interval of time, about 100 million years ago.
Co-author and team member Jeffrey Wilson, assistant professor at the
University of Michigan, said, “Until the continents fully separated,
dinosaurs like Rugops and other animals used narrow land bridges to
colonize adjacent continents and roam within a few degrees of the South
The fossils were discovered on two separate expeditions that Sereno
led to Niger, one in 1997 and the other in 2000, which have brought to
light many new dinosaurs and the 40-foot-long crocodilian Sarcosuchus,
also known as “SuperCroc.”
Sereno recalls the day in 2000 when team member Hans Larsson, now an
assistant professor at McGill University in Montreal, spotted a jawbone
— and then, about two feet away, the rest of the skull. “It was hard to
see which end was the front, but we quickly realized we were looking at
a brain case, and that it was probably an abelisaur — a huge find,”
Both Rugops and Spinostropheus came from the Cretaceous Period, when
this area of Africa featured broad rivers and lush plains. Today it is
located in the southern Sahara Desert, part of the Republic of Niger.
Expeditions to the Sahara led by Sereno in 1993, 1995, 1997 and 2000
unearthed a gallery of new dinosaurs, including the first from Africa’s
Cretaceous Period; they include Afrovenator, Jobaria, Deltadromeus,
Carcharodontosaurus and Suchomimus.
A National Geographic Explorer-in-Residence since 2000, Sereno has
received 11 research grants from the Society’s Committee for Research
and Exploration as well as two grants from the Society’s Expeditions
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