Page 89 - Prehistoric Animals

Mono-Clon-A-Us

Monoclonius

What is a Dinosaur ? tinct genus of herbivorous ceratopsian dinosaur whose
Known as a Dinosaur Monoclonius (single sprout) is an ex-
fossils were found in the Late Cretaceous layers of
the Judith River Formation in USA, and the Dinosaur
Park Formation in Canada. They have been dated to
between 75 and 74.6 million years ago.

Monoclonius is considered by many to be a
‘nomen dubium’ , meaning, ‘pending further study’.
Since its discovery and naming by Edward Drinker
Cope's in 1876, errors have been found in Cope’s initial
published findings on the fossils. Other finds believed
to be of the genus Monoclonius have also raised doubts
and some believe require further study; hence the la-
belling, ‘nomen dubium’.

Confirmed Fossils of Monoclonius, however, can
tell us a lot about this ancient Dinosaur. One thing we
do know for sure is that it had a very big scull. The scull
supported three large horns, one on its snout and two
at the back behind its eyes. Behind those it had a heavy
armoured frill. The lower jaw of its mouth was bill
shaped; typical of an herbivore that lived on plants and
twigs. The scull measured, from frill to snout, approxi-
mately 2 metres. To support such a large scull its body
must have been very big and muscular. Its estimated
size has been made at around 6 to 7 meters long and its
estimated weight about 2 to 3 tonnes. Its legs would
have been short and stocky, with flat padded feet. With
its eye set at the back of its head it would have walked
with its head drooping downwards to get a clear view
ahead.

Monoclonius must have been a very big animal.
However, as a dinosaur it was relatively small. Stand-
ing next to a fully grown Diplodocus it would have
looked positively tiny.