EXTINCTION
OF DINOSAURS
Dinosaurs disappeared from Earth
about 65 million years ago. There are no specific reasons why dinosaurs have
extincted but scientists predict many reasons for it. Some of the reasons are:
· Appearance of mammals is one of the reasons because mammal ate too many dinosaur eggs .
· Ovarpopulation is another reason.
· Changes in climate, continental drift, volcanic erruptions, and shifts in the Earth’s axis are held responsible for dinosaur exinctions.
Scientists do not know for sure why dinosaurs became extinct. They have many different theories, some of which explain the extinction as something that happened gradually over a long period of time. Other theories suggest that a single catastrophe caused the dinosaur population to die off rather suddenly. And some scientists believe the dinosaur population had been gradually getting smaller and then was finished off by some dramatic event.
Some who believe gradual changes brought about the dinosaurs' end suggest that, as more and more mammals appeared, the dinosaurs had trouble competing with them for food sources. And these mammals may have eaten dinosaur eggs in such large numbers that fewer and fewer baby dinosaurs were born. Some experts believe that widespread disease killed off dinosaurs. Many suggest that gradual climate changes-from continuously warm, mild weather to seasonal variations with hot summers and cold winters-affected the dinosaurs. Scientists are not sure whether dinosaurs were warm-blooded or cold-blooded (and there may have been some of each). If they were cold-blooded, meaning that their body temperature changed depending on the temperature of their surroundings, it would have been difficult for such large animals to survive extreme temperatures. Smaller cold-blooded creatures can burrow under the ground, for example, to escape both heat and cold. But most dinosaurs were simply too large to do that.
Simran Dayal
8-Glenn
· Appearance of mammals is one of the reasons because mammal ate too many dinosaur eggs .
· Ovarpopulation is another reason.
· Changes in climate, continental drift, volcanic erruptions, and shifts in the Earth’s axis are held responsible for dinosaur exinctions.
Scientists do not know for sure why dinosaurs became extinct. They have many different theories, some of which explain the extinction as something that happened gradually over a long period of time. Other theories suggest that a single catastrophe caused the dinosaur population to die off rather suddenly. And some scientists believe the dinosaur population had been gradually getting smaller and then was finished off by some dramatic event.
Some who believe gradual changes brought about the dinosaurs' end suggest that, as more and more mammals appeared, the dinosaurs had trouble competing with them for food sources. And these mammals may have eaten dinosaur eggs in such large numbers that fewer and fewer baby dinosaurs were born. Some experts believe that widespread disease killed off dinosaurs. Many suggest that gradual climate changes-from continuously warm, mild weather to seasonal variations with hot summers and cold winters-affected the dinosaurs. Scientists are not sure whether dinosaurs were warm-blooded or cold-blooded (and there may have been some of each). If they were cold-blooded, meaning that their body temperature changed depending on the temperature of their surroundings, it would have been difficult for such large animals to survive extreme temperatures. Smaller cold-blooded creatures can burrow under the ground, for example, to escape both heat and cold. But most dinosaurs were simply too large to do that.
Simran Dayal
8-Glenn