Page 23 - Prehistoric Animals

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Brachiosaurus

What is a Dinosaur ?
Known as a Dinosaur

Brachiosaurus is a genus of, sauropod (lizard hipped) dinosaur, that lived in the Late Ju-
rassic, around 154 to 150 million years ago. It’s believed to have been around 18 to 22 metres long
and weighed in at around 31 to 52 tonnes. The first fossils found in western Colorado, USA, were
named by Elmer S Riggs in 1903; Brachiosaurus. (old Greek for ‘arm lizard’) altithorx
(meaning, ‘Deep chest’)

Brachiosaurus, along with similar large sauropods, are recognisable by their long necks,
small heads, and forelegs that are much longer than their hindlegs. This limb difference, gives
their torso a downward slope, and being Herbivores their long necks allows them to reach up and
feast on fresh vegetation 9 meters off the ground. However, some have begun to question the
popular image of large sauropods supported only by their short hindlegs, reaching upwards to
feed. They claim it’s too energy consuming and stressful, and doubt whether these large sauro-
pods ever did this.

Over the years other sauropod fossils found in Europe and Africa were at first thought to
be of the genus Brachiosaurus. This has since been found incorrect; they belonged to a different
genus. One to the genus Giraffatitan and the other to Lusotitan. This makes the Brachiosaurus
altithorx a unique sauropod, being the only complete specimen of its genus.

genus