High-Bandwidth Version
Search Evolution  
Click to return to the Evolution Home Page
darwin change extinction survival sex humans religion
What Killed the Dinosaurs?

Introduction | Asteroid Impact | Volcanism | Mammal Competition | Continental Drift | Conclusion

We will never know exactly what happened 65 million years ago, but we can come close.

Most scientists agree that an asteroid or comet put a dramatic exclamation point at the end of the Cretaceous period. It is also widely acknowledged that continents shifted, sea levels dropped, and volcanoes erupted across Earth's surface. Most paleontologists would even grant that mammals probably competed to some extent with dinosaurs.

With all of these pieces to the puzzle in hand, the question remains: What role did these phenomena play in the extinction of the dinosaurs?

While the answer to this question remains a mystery, the question itself is far more refined than the one scientists were asking just a few decades ago. We're getting closer to knowing what killed the dinosaurs.

And so, for now, we can be satisfied maintaining several viable hypotheses. It's likely that one of them -- or all of them in combination -- holds the answer. In time, with more evidence, we will undoubtedly get closer to knowing for sure.

Introduction | Asteroid Impact | Volcanism | Mammal Competition | Continental Drift | Conclusion

  related web activities  
Riddle of the Bones
Piece together clues about our early ancestors.
A Modern Mass Extinction?
Are we in the midst of one? And if so, did we trigger it?
Deep Time
Explore 4 billion years of life on Earth.
  related topics  
  Deep Time/History of Life  
  What Is Science?  
  Evidence for Evolution  
Videos Web Activities Site Guide About the Project FAQ Glossary Site Map Feedback Help Shop