Skip to Content

Island life

Geological factors help determine how long islands survive—and how evolution unfolds in places like the Galápagos.
February 26, 2020
Getty

When a hot plume of rock rises through Earth’s mantle to melt through the crust, it can create both a volcanic ocean island and a swell in the ocean floor hundreds to thousands of kilometers long. Eventually the island is carried away by the underlying tectonic plate, and another grows in its place. Over millions of years, this geological hot spot can produce a chain of islands—on which life may flourish before they sink, one by one, back into the sea.

The amount of time an island spends above sea level can determine the course of evolution there, and yet the mechanisms that control this have been unclear. Now, after analyzing 14 volcanic chains, Kimberly Huppert ’11, PhD ’17, and professors Taylor Perron and Leigh Royden of the Department of Earth, Atmospheric, and Planetary Sciences have found that an island’s life span is related to the speed of the underlying plate and the size of the swell generated by the plume. The Hawaiian Islands, for example, persist for millions of years longer than the Galápagos because while the plates beneath the chains travel at similar speeds, it takes longer for the plate to slide over the larger Hawaiian swell.

The Galápagos Islands’ shorter life span may also help explain why they host such unique and rapidly evolving species. “You can imagine all these organisms living on a sort of treadmill made of islands, like stepping stones, and they’re evolving, diverging, migrating to new islands, and the old islands are drowning,” says Perron. “What Kim has shown is there’s a geophysical mechanism that controls how fast this treadmill is moving and how long the island chains go before they drop off the end.”

Keep Reading

Most Popular

This startup wants to copy you into an embryo for organ harvesting

With plans to create realistic synthetic embryos, grown in jars, Renewal Bio is on a journey to the horizon of science and ethics.

VR is as good as psychedelics at helping people reach transcendence

On key metrics, a VR experience elicited a response indistinguishable from subjects who took medium doses of LSD or magic mushrooms.

This nanoparticle could be the key to a universal covid vaccine

Ending the covid pandemic might well require a vaccine that protects against any new strains. Researchers may have found a strategy that will work.

Stay connected

Illustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.