[Animals] Which animals are most likely to survive climate change?

[BirSaNN]

Even the toughest species might have a limit under climate change.

As climate change transforms our world, the impacts will be felt unequally, with some animals struggling to survive and others finding ways to overcome the resulting challenges.

This phenomenon is increasingly described as the "winners and losers under climate change," said Giovanni Strona(opens in new tab), an ecologist and former associate professor at the University of Helsinki, now a researcher at the European Commission. Strona led a 2022 study, published in the journal Science Advances(opens in new tab), that found that under an intermediate emissions scenario, we stand to lose, on average across the globe, almost 20% of vertebrate biodiversity by the century's end. Under a worst-case warming scenario, that loss rises to almost 30%.

So which animals are the "winners," and how well will they really fare under increasing temperatures, drought and habitat loss?

 

Everything is connected
There's no doubt about the threats to Earth's biodiversity from climate change and habitat destruction. In 2022, the World Wildlife Fund (WWF) released the Living Planet Report(opens in new tab), which described a 69% decline in the relative abundance of monitored species since 1970. Meanwhile, 1 million species now face extinction across our planet because of these twin threats, according to the report. There's now mounting evidence that Earth is experiencing its sixth mass extinction.

Climate change contributes to these extinction risks in complex and interconnected ways, some of which are still-unknown. It will affect po[CENSORED]tions directly by inducing extreme weather events, like storms; by driving up temperatures or reducing rainfall beyond the thresholds a species needs to survive; and by shrinking key habitats on which animals depend. 

As Strona's research showed(opens in new tab), climate change can also have indirect effects that ripple through an ecosystem. He and his team built several model Earths incorporating over 15,000 food webs to represent the connections of many thousand terrestrial vertebrate species. Then, they simulated various climate and land-use change scenarios in these ecosystems. 

Their simulations showed that when climate change directly caused the loss of one species, it resulted in a cascading loss of several species that depend on that one species for food, pollination or other ecosystem services. This domino-like effect, known as "co-extinction," will drive the bulk of terrestrial vertebrate species diversity declines under projected climate change, the research predicts. Because the study didn't model the impact of climate change on communities of insects or plants, these findings are likely also optimistic, Strona said.

The huge complexity of animal relationships within natural ecosystems, plus the uncertainty over how extreme climate change will get, makes it difficult to drill down into such data and pinpoint which animals will do better than others as our world warms. However, Strona's research did pick up on a general trend: "What we found is that larger species and species at high trophic [food chain] levels will be more adversely affected," he told Live Science.

So animals with lower positions in the food chain, such as insects or rodents, may fare better in a warming world.

Related: What would happen to Earth if humans went extinct?

Adaptable animals
Larger species tend to reproduce more slowly, and that's another clue researchers have connected to climate vulnerability.

Another recent study, published in the journal Global Change Biology(opens in new tab), looked at 461 animal species across six continents and analyzed the disruptive effects of historical land-use and temperature changes on their po[CENSORED]tions. "What we found in our study is that species that breed really fast are really good at exploiting new habitats — taking energy and transforming it into offspring," study lead author Gonzalo Albaladejo Robles(opens in new tab), a conservation biologist at University College London, told Live Science. 

Faster breeding may benefit species in a changing climate because they're more adaptable to changing habitats; fast breeding cycles give these species an "opportunity to survive these peaks in environmental disruption," such as extreme weather or habitat loss, Albaladejo Robles explained. Meanwhile, slower-breeding animals showed the opposite trend in the study, and their po[CENSORED]tions declined when temperature and habitat changed.

link: https://www.livescience.com/which-animals-will-survive-climate-change