23 million years of evolution at risk in Madagascar

Madagascar is one of the most megadiverse countries on Earth, with about 90 per cent of its plant and animal species found nowhere else on the planet.

But - like other places, its biodiversity is under threat. Of the country's 219 known mammal species, 120 are listed as endangered. Experts say that's primarily due to human activity over the past two hundred years - especially habitat destruction and overhunting.

If all of Madagascar's endangered mammals were to go extinct, their lineages would be lost forever, and a new study appearing in the journal Nature Communications finds it would take the region 23 million years to recover from that biodiversity loss.

Researchers believe it will take about 3 million years for Madagascar to rebuild the biodiversity lost by the land-dwelling animals that have already gone extinct over the past 2,500 years.

Using a computer model, the paper looked at other regions as well, including New Zealand and the Caribbean, and found that Madagascar's recovery time would be far longer than anywhere else.

Steve Goodman, one of the paper's main authors, says immediate action is needed to protect the country's many species.

REPORT: One million species facing extinction

Losing numerous species would be catastrophic on many levels, potentially leading to the collapse of the ecosystem while having "dramatic implications for human livelihoods in the region," the paper says.

“There is still a chance to fix things, but basically, we have about five years to really advance the conservation of Madagascar’s forests and the organisms that those forests hold,” Goodman says in a statement.

“We can't throw in the towel. We’re obliged to advance this cause as much as we can and try to make the world understand that it’s now or never.”

Image at top: The brown mouse lemur (pictured above) is one of Madagascar's endangered species. Since humans arrived in Madagascar, 17 species of lemur have gone extinct. (Chien C. Lee)