JUL 30, 2016

Easter Island Extinctions

WRITTEN BY: Kathryn DeMuth Sullivan

“Ecosystems don’t collapse, they shift from one steady state to another, and that’s simply what happened here on Rapa Nui.”
 

 
Jut Wynne, an assistant research professor in the Department of Biological Sciences and the Merriam-Powell Center for Environmental Research at Northern Arizona University is visiting the island this summer to continue a nearly decade-long project of studying, classifying and hopefully conserving the last true natives of Rapa Nui — ten species of insects endemic to the island.

So far, Wynne has discovered seven species of springtail, tiny insects whose defining feature is a spring-loaded tail that flips them into the air and away from danger — a built-in ejector seat. He has also found two isopod species, popularly known as “roly-polys”, and one species of book louse. While he has ample evidence that other species existed in the past, his upcoming research could uncover more.

The 10 species he’s discovered likely represent only a portion of what was once on the island. Records indicate that many more once crawled across the island, but were wiped out by changes to the ecosystem and invasive species. The remaining insects have likely all retreated underground, where conditions likely reflect the Rapa Nui ecosystem that existed before humans arrived. They live chiefly in gardens of fern and moss gardens that provide the cool, damp surroundings they prefer.
 

“What caused that shift was a very fragile, fire-intolerant ecosystem and the arrival of humans timed inauspiciously with a extended drought period,” says Wynne. “And when that happened, it put a big strain on the ecosystem, we lost a lot of endemic plants in favor of a more homogenous environment, and we lost a lot of endemic animals … the only animals terrestrial in origin that are remaining on Easter Island are insects, and they are fleetingly few.”

Wynne first visited Rapa Nui, also known as Easter Island, in 2008, in pursuit of his childhood dream to see the island. He returned later that year to conduct a baseline study looking at one cave, which provided a basis for subsequent expeditions. Trips in 2009 and 2011 followed, during which he sampled over a dozen more caves and identified eight new species endemic to the island, bringing the total to ten. This summer, supported by a Fulbright fellowship, he hopes to expand his search to the cliffs, lakes and coast lines of the island, in addition to ramping up conservation efforts among the populace.

These caves, scientists believe, may be the only places where these species exist.
 


This article was republished from Discover Magazine. The writing may have been reorganized or cut for publication purposes.