Besides some of the most abundant—and most diverse—coral reefs in the world, the region supports mangroves, sea grasses, algae, mollusks, arthropods, fish, and other marine species in unmatched concentrations.
Scientists behind the new study say a single hot spot can last millions of years, and that the coral triangle hot spot is much older than previously thought, stretching as far back as the Miocene epoch, which lasted from 23 to 5 million years ago.
But hot spots don't last forever, and Earth's geology has much to do with it, the team says.
As tectonic plates vie for position, one edge eventually becomes subducted, or submersed, beneath the other. The resulting uplift can produce new islands and mountains.
But during this process, nearby terrain tends to normalize, making habitat less diverse. As a result, species that depend on diverse terrain must migrate or die out.
"Usually if there are mass extinctions, they're more severe when you are in that second phase of the hot spot cycle," said Renema, who is also a National Geographic grantee. (National Geographic News is owned by the National Geographic Society.)
The new study suggests that species diversity peaks not necessarily where tectonic plates collide head-on, but at places where the meeting is messy and shallow seas of varying depths form.
As tectonic plates vie for position, one edge eventually moves beneath the other. Many millions of years later, the resulting uplift can produce new islands and mountains.
Following Hot Spots
David Jablonski, a paleontologist at the University of Chicago, described the researchers had a "really interesting hypothesis."
He said it's the first comprehensive presentation of an idea— that plate tectonics generate biodiversity—that first emerged in the 1980s.
Jablonski says it remains to be seen whether the abundance of marine species found today in the coral triangle has truly been hopping the globe or is in a process of contracting, with the West Pacific as a sort of last holdout.
Renema, the lead study author, concedes that more work needs to be done to track diversity hot spots more closely over time.
"We have this idea," he said, "And now we can test it."
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