"Stegasaurous died out 145 million years ago, T Rex 72-65 million years ago, the Stegasaurous was as old to the T-Rex as the T-Rex is to us.
Grasses evolved about 70 Mya."
"Humanity was likely nearly wiped out about 900,000 years ago when our ancestors were reduced to about 1280 breeding individuals and stayed around that many for 117,000 years."
#10 now that is some Darth Plagueis level of irony.