ecosystems thought propelled coevolution pollinating insects ref name crepet ref social insects appeared around time although account small parts insect family tree form total mass insects ref name wilsonh lldobler eusocialityoriginconsequences ref humans evolved lineage upright walking apes whose earliest fossils date although early members lineage chimp sized brains big modern humans' signs steady increase brain size long running debate whether ''modern'' humans descendants
Natural science Earth science Paleontology