As a consequence of climate change, some endothermic animals (colloquially known as ‘warm-blooded’) are changing shape and have larger beaks, legs and ears to better regulate their body temperature as the planet warms. These are the conclusions of a study that has just been published in the journal Trends in Ecology and Evolution.
“Many times, in discussions about climate change, a very anthropocentric vision predominates: can human beings overcome this? What technology is going to solve it? ”, Reflects Sara Ryding, researcher at Deakin University (Australia) and author of the work. “It is high time that we recognize that animals also have to adapt to these changes, which are also occurring on a much shorter time scale than ever before . Climate change, created by us, is putting a lot of pressure on them and, although some species will adapt, others will not. “
Ryding points out that climate change is a complex and multifaceted phenomenon that has been occurring progressively, making it difficult to identify a single cause of shape change. But these changes have been taking place across wide geographic regions and across a diverse range of species, so there is little in common other than climate change.
Groups most affected
Birds are a group especially affected by changes in shape. For example, several species of Australian parrots have shown, on average, a 4 to 10% increase in beak size since 1871, and this in turn is positively correlated with the average summer temperature each year. In another type of North American songbird ( Junco hyemalis ), a link has been observed between increased beak size and short-term extreme temperatures in cold environments. In the case of mammals, the authors have found increases in the length of the tail of some species of mice, and of tail and legs in shrews.
“So far, the increases we have registered are small, less than 10%, so it is unlikely that the changes will manifest immediately,” explains the researcher. “However, prominent appendages, such as the ears, are expected to increase.”
The next step will be to investigate first-hand shapeshifting in Australian birds by 3D scanning museum bird specimens from the last hundred years. This will give your team a better understanding of which birds are changing the size of the appendages due to climate change and why.
“Shape change doesn’t mean that animals are dealing with climate change and that everything is ‘okay,’ says Ryding. “It just means that they are evolving to survive, but we are not sure what the other ecological consequences of these changes are, or that all species are capable of changing and surviving.”
Referencia: Ryding et al. 2021. Shape-shifting: changing animal morphologies as a response to climatic warming. Trends in Ecology and Evolution.
