The Skull of Nigersaurus, an Unusual Sauropod Dinosaur from the
Cretaceous of Africa
Common Language Summary A bizarre sauropod
dinosaur from Africa.
By modern standards, most dinosaurs are pretty unusual animals.
Nigersaurus taqueti, however, is bizarre by even
dinosaurian standards. The delicate bones of this sauropod were
collected from 110 million-year-old rocks of the Ténéré Desert,
Niger. Studying these fossils required high-tech approaches
(such as CT scanning, 3D computer visualization, and rapid
prototyping) and traditional techniques (such as sculpture). The
end result was the first good view of the skull of a
rebbachisaurid, a group of sauropod dinosaurs related to the
better known Diplodocus and Apatosaurus. The skull
of Nigersaurus was particularly bizarre. Its more than
500 teeth were all positioned at the very front of the skull,
and formed a tight-fitting dental battery. Microscopic studies
of the teeth show that they were worn down very quickly and then
replaced by others in the battery. These high rates of tooth
wear are surprising given that the skull seems too lightly built
to have engaged in extensive chewing. The brain of
Nigersaurus was very small relative to body size and was
basically primitive in structure. The animal was largely driven
by instinct. Its olfactory lobes of the brain were smaller than
in other sauropods, suggesting the sense of smell was less
important. The inner ear turned out to be very informative. The
hearing organ (cochlea) of sauropods generally is rudimentary
but is even smaller in Nigersaurus, suggesting that its
discrimination of airborne sounds was poor. The inner ear also
provides information on head posture, and most diplodocoids have
a strongly down-turned head. Nigersaurus, however, took
this trend to its extreme in that its head pointed straight
down. Although at first a surprising finding, it helps makes
sense of the unusual feeding apparatus, showing that
Nigersaurus was a ground-feeding “lawn-mower” using its
front-mounted dentition to crop low-growing plants.
A technical article was published on 15
November 2007 in
PLoS ONE
This website provides supplementary information as an
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Ryan Ridgely, is responsible for
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