Having ruled the Earth for more than 100million years by a drastic lowering of the sea level. One site now the dinosaurs suddenly died out 65 million years ago. clearly identified with this is in the sea off the coast so too did ammonites, most marine reptiles, many of Yucatan, which involved the impact of an asteroid 6 miles (10 km) in diameter. Its shape suggests that species of plankton, and many marsupials.
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| The K/T Boundary, the black layer between cretaceous and tertiary rock is made from material ejected from an asteroid impact |
Some how however the small and primitive mammals survived.
it hit at an angle, scattering much debris across plus most species of bird insect, lizard and amphibian. North America.
it hit at an angle, scattering much debris across plus most species of bird insect, lizard and amphibian. North America.
In some parts of the world more than half of all plant The end of the Cretaceous (K) and beginning of the Tertiary T) period is known as the KT boundary species also became extinct What happened? Scientists have long debated event. Yet it is not clear why some groups of animal how quickly the extinctionsoccurred-whether in the were devastated whereas others survived.
Smaller space of a few catastrophic years, or several millennia. and burrowing animals were less affected than The most likely theories suggest one or several large large surface dwellers, and free-swimming species asteroid impacts, which would have melted the suffered more than bottom-feeding marine ones.
But Earthiscrust causing massive atmospheric disruption the survival of birds suggests that the atmospheric and creating huge tsunamis and firestorms, followed disruptions may have been fairly short lived.
