As the environment starts to change in more dramatic and extreme ways, many species are likely to feel the effect. Whether it’s a shift in their range as ecosystems alter, or disruptions in their ability to find food, some species will benefit while others will inevitably lose. It is usually thought that the current rate at which the climate is changing is too rapid for animals to adapt, but a new paper suggests that this may not always be the case.
“There is a wealth of fossil evidence which suggests rapid climate shifts don’t provide enough opportunity for many species to adapt, meaning they became extinct or restricted to smaller areas of suitable habitat,” explains Dr Jack Lighten, who co-authored the study published in Royal Society Open Science. Species that are slow-growing and have a long maturation time are thought to be particularly at risk, as changes to their genes cannot be passed down at a quick enough rate.
But there are some long-lived, slow-growing species that have defied all odds and survived multiple extinction events, some of which completely altered the face of the planet. So Lighten focused on sharks, skates, and rays in order to investigate just what it was that allowed them to persist, even when 96 percent of all other animals perished. This suggests that they have some sort of evolutionary strategy to withstand massive environmental changes.
Focusing on two populations of winter skate (Leucoraja ocellata) in the Canadian Atlantic, Lighten found that the population living in the shallower, warmer habitat of the Gulf of St Lawrence (which only appeared around 7,000 years ago) had thousands of changes in gene expression when compared with the more archaic population of skate that typically live in the much deeper waters of the Scotian Shelf. This has seemingly resulted in the warm water fish shrinking in size by 45 percent and speeding up their maturation time to adapt to the toastier water.