Rapid Evolution in a Climate-Changed World
Around the world, animals are getting smaller. According to a new paper, this shrinkage isn't a coordinated effort -- the average size of animal species is decreasing because of climate change and other ways that people have reshaped the globe.
Biologist Andrew Hendry, whose research launched the field in the '90s, told Wired, "We had this impression that well, actually, maybe this rapid evolution thing is not so exceptional. Maybe it's actually occurring all the time, and people just haven't emphasized it."
But, this recent paper reexamines previous work and takes a hard look at rapid evolution: how different species change in response to changes in their environments, especially those that have experienced "human disturbance." The researchers put together a data set with more than 7,000 examples of rapid evolution, including tracking lifespans and body sizes.
Wired: How Animals Are Rapidly Evolving Because of Climate Change, November 29, 2021.
Why This Matters
The new dataset will help researchers better understand the human impact on the natural world. The clearest certainty is that people have significantly impacted the natural world. Climate change is everywhere, so the animals experiencing some sort of rapid evolution could be anywhere on the globe.
There are also plenty of human impacts in addition to climate change. Pollution has changed populations of Russian birch trees; overfishing, especially when people target the biggest fish, leaves a pool of smaller fish to carry on. And because ecosystems evolve together, changes to any one animal or plant can have knock-on impacts for other species, humans included.
The Economist: Can sea creatures adapt to climate change?, May 14, 2020.
Evolve, Or Else
The stakes for plants and animals to change are high: some species are changing; others are already on the move in search of more habitable climates for their health. Others that aren't able to make changes to survive in the new reality created by people risk decline and possible extinction.
"That may seem grim," Wired writes, "but …maybe that's just a sign that humans are not immune to the feedback loops that govern every other living thing. The animals we know will change or disappear, and new ones will evolve to take their place -- life will endure, even if life as we know it doesn't."
Reactions: How is Climate Change Affecting Hibernation?, January 22, 2022.
Pacific Community: Pacific Tuna: Feeling the Heat, July 27, 2021.