Scientists used to think that a warmer climate was the reason for the shrinking of birds, but a new study from Lund University shows that this may not be the case.
In recent decades, hundreds of bird species have become smaller. Since it is easier for a small animal to keep its head cool than a large one, it has long been thought that this is due to rising temperatures.
A new study published in Nature Ecology & Evolution models the ability of birds to radiate and produce heat. It found that the effect of getting smaller is so small that it is unlikely to be significant.
– The conclusion is that it is unlikely that animals shrink to better cope with rising temperatures, said Andreas Nord, a biology researcher at Lund University, in a press release.
However, it is still unclear why birds and other animals are shrinking. In terms of competition, it is an advantage for birds to be slightly larger, for example when choosing a mate or even food. However, the researchers stress the importance of continuing to study how animals and nature change over time.
– For policymakers to make decisions that effectively protect the health and welfare of wildlife and livestock in a changing climate, research must explain not only how animals are affected, but also why. We are now continuing to find alternative explanations for why animals are shrinking, which is one of the great mysteries of our time, says Nord.