300 – 200 million years ago

Year forty-five

Birds of a feather

Insects had developed flight by the time Earth was 43, but reptiles were not able to fly until Earth's 44th birthday (around 200 million years ago). The most successful creatures to take to the air were the birds, and the most important steps in the art of flight were the development of feathers, lightweight bones and strong muscles.

The first bird evolved just before Earth's 45th birthday. That is just over one year ago in our pretend person's life, but about 140 million years ago in real time.

The skeletons of the earliest birds are very similar to some of the dinosaurs, which had feathers, a wish bone, bird hips, and some had long arms — all the characteristics of a bird. The first birds probably evolved from a bipedal (two-legged) dinosaur like Compsognathus.

The first bird, Archaeopteryx, had a reptile-like head and jaws with teeth, three claws on its hands and a long bony tail — but it also had feathers. It ate insects, flew or glided from tree to tree looking for food and used its clawed hands to climb.

And in the last few million years

Hundreds of different kinds of birds evolved from Archaeopteryx. By about six months ago in Earth's life, all the modern groups of birds had developed.

Birds vary considerably in shape and size, from the Cuban bee humming bird, which is 5.8 cm long and just under two grams in weight, to the ostrich, which is 2.75 m tall and can weigh over 150 kg.

The largest bird ever to live was the elephant bird of Madagascar (or roc), which was four metres tall and weighed over 450 kg, but it couldn't fly.

The biggest bird ever to leave the ground was called Argentavis. It measured 7.3 m from wing tip to wing tip and flew over South America about two months ago in Earth's life (about 16 million years ago in real time).

Back to the beginning of the timelineEarth blooms

A number of different vascular plants had evolved since they first left the protection of the water to live on dry land, and amongst these were ferns, some as tall as trees.

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