Illustration of the aftermath from the destruction caused by a comet or asteroid that impacted the Earth. A skeleton of a T. Rex lies amongst the smashed trees. After a few months of cold and darkness, seeds, spores and surviving plants will soon germinate and grow again, surviving animals (including mammals) underground in burrows, in tree-holes and elsewhere will come out again, heralding the end of the Cretaceous and a new age; the Palaeogene of the Cenozoic Era has started.