Do you think the breakup of Pangea led to the extinction of some dinosaurs? What makes you think that?

Generally speaking, the extinction of the dinosaurs was catastrophically finalized by the Chicxulub impact and the subsequent worldwide ecological changes. However, some data suggests that certain dinosaur populations were decreasing in diversity prior to the impact. We should also be conscious of the fact that our data does not necessarily represent a true cross-section of life during the Mesozoic, due to a variety of factors skewing the fossil record and our access to it. Nevertheless, it would be fair to say that events related to continental rifting may have influenced extinctions; not necessarily because dinosaurs were falling into volcanoes, but because of ecological changes tied to the rifting process.

The breakup of Pangea was a long-term and complicated process that was not particularly different from the rifting we see today in places like East Africa. There are at least two significant effects that rifting produces; climate change as a result of previously connected land masses becoming geographically distinct, and climate change as a result of volcanic events tied to the movement of the plates.

One way in which changing the size and shape of land masses influences climate has to do with rainfall; large land masses tend to have arid interiors simply due to rain developing over the ocean and not being able to sustain itself over hundreds of miles of land. There were almost certainly changes in ocean and air currents as well, leading to different weather patterns in different regions depending upon the interaction of these factors.

In terms of tectonic events, volcanism can release a lot of carbon dioxide, a greenhouse gas, which can alter the local as well as global temperatures, and all related ecological factors. This and other gases can also blanket certain areas, rendering the air unbreathable, let alone covering them with lava. The Deccan Traps are an example of this. 

Thus, the breakup of Pangea could have contributed to dinosaur extinctions by:

• generally reducing the amount of land available to an animal


• changing the local and global climate


• rendering certain regions uninhabitable due to volcanic events