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What are snakes? Evolution and biology

By |2018-04-15T00:32:41+00:00September 16th, 2017|Biology|

Two pythons Snakes evolved from lizards only about 150 million years ago, during the Jurassic Period. This is during the time of the dinosaurs, about the same time that the first birds evolved from small dinosaurs. Like birds and mammals, though, snakes really began to take over after most of the dinosaurs died about 95 million years ago, at [...]

What are turtles? Biology and Evolution

By |2018-04-21T11:56:44+00:00May 26th, 2017|Biology|

Evolution of turtles: Seychelles tortoise (Jardin des Plantes, Paris) Evolution of turtles The first turtles began to evolve from earlier reptiles about 225 million years ago, during the Triassic period. By about 210 million years ago, they looked pretty much like modern turtles. Turtles are one of the oldest kinds of reptiles that [...]

What are reptiles? Biology and Evolution

By |2018-04-21T11:56:35+00:00May 26th, 2017|Biology|

Boa Constrictor snake Some kinds of amphibians evolved into reptiles about 300 million years ago. At this time, plate tectonics had moved more and more of the land on Earth into one big continent called Pangaea. All the land being together changed the weather so that it was drier and colder than before. That [...]

Duck-billed platypus – Biology and Evolution

By |2017-05-26T16:14:18+00:00May 26th, 2017|Biology|

Duck-billed platypus swimming Probably the very first mammals that evolved from reptiles about 200 million years ago were small animals covered with fur that still laid eggs like reptiles, but their babies got milk from their mothers like mammals. Most of the mammals like this have died out now, but one survivor is [...]

How do Opossums carry their babies? Biology

By |2018-04-16T08:12:58+00:00May 26th, 2017|Biology|

Opossum The earliest mammals, about 200 million years ago, hatched from eggs and then got milk from their mothers, like the duck-billed platypus. But soon after that, about 125 million years ago, these mammals evolved into mammals that were born alive, but helpless and tiny. These tiny babies then lived in a pouch [...]

Evolution of Horses – Where do horses come from?

By |2017-09-16T22:18:43+00:00May 26th, 2017|Biology, Central Asia|

Eohippus - an early kind of horse When mammals first began to grow larger, after the dinosaurs became extinct about 70 million years ago, some of them evolved into the earliest ancestors of horses. The first horses evolved in North America. They were about the size of dogs. They had three toes, lived [...]

Chimpanzee Evolution and Biology

By |2018-09-03T10:22:42+00:00May 26th, 2017|Africa, Biology|

What is a chimpanzee? Chimpanzees evolved in the Tertiary period, about five million years ago, when they split off from earlier primates in Africa. When did chimpanzees evolve? Chimpanzees are descended from earlier primates. They probably split off from the branch that became modern humans about five million years ago, but they're still [...]