My Timeline

4,550 billion years ago the Earth was formed.

550 mya (million years ago) was the Pre-Cambrian Period. It had the first soft bodied creatures. Also the first living cells appear. Also the Earth’s surface is covered with volcanoes. Volcanoes sent out clouds and gas that collected in a thick layer around the earth. It started to rain and then it flooded and made oceans.

510 mya was the Cambrian Period. It had the first creatures with skeletons. The creatures were created by the Cambrian explosion. The Cambrian Explosion was about 545 mya. The Cambrian Explosion was not an actual explosion, it was just when a whole bunch of creatures were created. It is just a point in time.

440 mya was the Ordovician Period. It had the first fish, the first creatures on land, and the first land plants. Once there were plants on land, there was food for animals to eat. The first animals to move from water to land were arthropods, meaning spiders, millipedes and insects.

408 mya was the Silurian period.

352 mya was the Devonian Period, which had the first amphibians, Scientists think fish grew legs (which is now a lizard) and lungs to help live in shallow water.

290 mya was the Carboniferous Period which had the first forests and the first flying insects.245 mya was the Permian Period which had the first swimming reptiles.

200 mya was the Triassic Period which had the first reptiles and dinosaurs.

144 mya was the Jurassic Period which had the first mammals, the first birds, and the continuation of the dinosaurs.



2.6 mya Quartenary Period which had the most recent Ice Age with Sabretooth Tigers and Mammoths and all that

1.8 mya to present time was the Tertiary Period. HUmans evolved, first horses, grass, and cats.