Nearly all of us now know--or think we know--how the dinosaurs perished: some 65 million years ago, a giant asteroid or comet struck the earth, spewing huge amounts of dust and debris into the air. That dust, according to a widely accepted theory first proposed by Nobel laureate Luis Alvarez, was circulated by the winds and enshrouded the earth for months, blocking sunlight and causing temperatures to plummet. As a result, the dinosaurs, and 70% of all other terrestrial species, were wiped out.
But this scenario was rudely challenged last week by Kevin Pope, a former NASA scientist. Reviewing recent studies...
To continue reading:
Want the full story?
Get TIME the way you want it
Week Digital Pass — $4.99
Pay-As-You-Go DIGITAL ACCESS — $2.99
Year ALL ACCESS — Just $30! Best Deal!
Print Magazine + Digital Edition +
Subscriber-only Content on TIME.com
Learn more about the benefits of being
a TIME subscriber
If you are already a subscriber sign up — registration is free!