It would take 50 million years to recover New Zealand's lost bird species

It would take 50 million years to recover New Zealand's lost bird species
A Kaka bird. Credit: Juan Carlos Carcia / Current Biology

Half of New Zealand's birds have gone extinct since humans arrived on the islands. Many more are threatened. Now, researchers reporting in the journal Current Biology on August 5 estimate that it would take approximately 50 million years to recover the number of bird species lost since humans first colonized New Zealand.

"The we make today will have repercussions for millions of years to come," says Luis Valente of Museum für Naturkunde in Berlin. "Some people believe that if you leave nature alone it will quickly recuperate, but the reality is that, at least in New Zealand, nature would need several million years to recover from human actions—and perhaps will never really recover."

The biodiversity observed today is the result of millions of years of evolutionary time, Valente explains. Extinctions caused by human activities erase this history. While the number of lost or threatened often has been quantified, the broad-scale evolutionary consequences of human impact on island biodiversity rarely have been measured.

In the new study, Valente and colleagues developed a method to estimate how long it would take for islands to regain the number of species lost due to humans. They realized that New Zealand would be an ideal system to apply and demonstrate this new method.

It would take 50 million years to recover New Zealand's lost bird species
A Kakapo bird. Credit: Andrew Digby

"The anthropogenic wave of extinction in New Zealand is very well documented, due to decades of paleontological and archaeological research," Valente says. "Also, previous studies have produced dozens of DNA sequences for extinct New Zealand birds, which were essential to build datasets needed to apply our method."

Using computers to simulate a range of human-induced extinction scenarios, the researchers found that it would take approximately 50 million years to recover the number of species lost since 's first arrived in New Zealand. If all species currently under threat are allowed to go extinct, they report, it would require about 10 million years of evolutionary time to return to the numbers of today.

It would take 50 million years to recover New Zealand's lost bird species
A Kakapo bird. Credit: Andrew Digby / Current Biology

Valente says they now plan to estimate evolutionary return times for several islands worldwide to see whether there are certain that have more evolutionary time under threat. They also want to assess which anthropogenic factors play the most significant role in determining those losses.

For New Zealand, Valente says, there is a bright side. "The conservation initiatives currently being undertaken in New Zealand are highly innovative and appear to be efficient and may yet prevent millions of years of evolution from further being lost," he says.


Explore further

Caribbean bats need 8 million years to recover from recent extinction waves

More information: Current Biology, Valente et al.: "Deep Macroevolutionary Impact of Humans on New Zealand's Unique Avifauna" http://cell.com/current-biology/fulltext/S0960-9822(19)30785-7 , DOI: 10.1016/j.cub.2019.06.058
Journal information: Current Biology

Provided by Cell Press
Citation: It would take 50 million years to recover New Zealand's lost bird species (2019, August 5) retrieved 21 August 2019 from https://phys.org/news/2019-08-million-years-recover-zealand-lost.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
933 shares

Feedback to editors

User comments

Aug 05, 2019
They clone them, if there are remnants of the originals in labs, collections. Could repopulate in a decade. Only timid and STUPID people stand in the way.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more