Primates first appeared just under 65 million years ago, after the age of the dinosaurs. The early primates lived in tropical rain forests. They were arboreal and had grasping hands and feet. As they evolved, primates became better-adapted to life up in the trees, developing binocular vision to enable them to judge distance with great accuracy. Today, there are more than 400 species of living primates, the majority of which are still most at home in the trees, but some species, including humans, now live on the ground.

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Evolution Alice Roberts

Emin

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Darwin knew that evolution could work only if there was inheritance. He could not have had a knowledge of modern genetics, but during the 20th century, it became clear that the genetic code he sought was contained in the chromosomes inside the nucleus of almost every cell of every living organism. Each human cell contains 20,000–25,000 genes, each of which has coded instructions for specific characteristics. The code is mainly in the form of a molecule of DNA, which includes four chemicals, called bases, arranged in pairs. Every gene is encoded by a specific sequence of base pairs.

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Evolution Alice Roberts

Geri