At last, the Age of the Mammals have dawned. Although the giant terror birds had it their way for around 15 million years to begin with, the mammals adapted swiftly to the fortunate climate changes, that favoured them instead of the killer birds. The small, insectivorous mammals, very quickly diversified into the niches that they had been denied since the time of the first Dinosaurs. Some, such as the Brontotheres, grew as large as modern Elephants (though they were related to horses, and rhinos) The Age of Mammals had begun. It still continues today.















The Precambrian Super-Eon The Hadean Eon The Archaean Eon The Proterozoic Eon The Phanerozoic Eon The Palaeozoic Era The Cambrian Period The Ordovician Period The Silurian Period The Devonian Period The Carboniferous Period The Permian Period The Mesozoic Era The Triassic Period The Jurassic Period The Cretaceous Period The Cenozoic Era The Tertiary Period The Palaeocene Epoch The Eocene Epoch The Oligocene Epoch The Miocene Epoch The Pliocene Epoch The Quaternary Period The Pleistocene Epoch The Holocene Epoch