At the end of the
Cretaceous Period (about 65 million years ago), the most common Dinosaurs were
the plant-eating Hadrosaur Family, who lived throughout Eurasia and North
America. Unlike many other Dinosaurs, the Hadrosaurs spent their entire
evolutionary lives in one period – the Cretaceous (about 80 million years in
duration). These Dinosaurs were in the Order of Ornithischians (Bird-hipped
Dinosaurs), and had thick-bodies, stiff tails, and tough beaks. The Hadrosaur
Family became well-known for their famous duck-bills, distinctive crests, and remarkable
teeth.
When naturalists first discovered
the Hadrosaurs in the 1850s, they were fascinated by the duck-like mouths.
Since these Dinosaurs had “duck bills”, the scientists reasoned that They lived
like Ducks. However later discoveries proved that these first scientists were
mistaken. The Hadrosaur Family were, in fact, land-dwelling Dinosaurs, who roamed
in large herds across the flatlands.
Today, scientists divide the
Hadrosaur Family into three groups based on the characteristics of their crests
and duck-bills. The first group is the transitional Dinosaurs from the Iguanodon
Family to the “true” Hadrosaurs. The second group, the Hadrosaurinae (which includes
Hadrosaurus and Maiasaura) has solid or small crests, and wider, more rounded
snouts. The third group is the Lambeosaurines, who have hollow crests and
shorter snouts. Of this group, Lambeosaurus
and Parasaurolophus were known for
their “big honking noses.”
Living in vast herds, the Hadrosaur
Family were considered the “Sheep” or “Cows” of the Cretaceous Period, since
They browsed on low-lying plants such as berries, ferns, and small
pine-trees. What made the Hadrosaur
Family a successful group of Dinosaurs were their teeth and jaws. Their teeth
formed a dental battery, with hundreds of teeth, which acted like two rasps
grinding against each other. Meanwhile, their upper jaws would swing outward
and scrape their teeth against the lower jaw. In this manner, Hadrosaurs could
turn their food into mush for easier digestion. (Mammals and Reptiles do not
chew their food this way.)
Enter the peaceful world of the
Hadrosaur Family. Imagine a vast herd of Dinosaurs serenely browsing ferns on
the flatlands of North America. As They slowly move across the land, various Dinosaurs
hoot contentedly to each other. Meanwhile, several Hadrosaurs are on guard for
a predatory Tyrannosaur rex. Feel
safe and protected amongst these plant eaters. Join Them and be surrounded by
the security and peace that Hadrosaurs offer.
No comments:
Post a Comment