These species that are shrinking with climate change. Like for example the robin. in Haute-Loire, it is slightly smaller than those in the North. It is an adaptation strategy.
Fanny, are you telling us that at home in Haute-Loire, robins are getting smaller and smaller ...?
Already they were not very fat, some birds like robins become rikiki..And it would not be a bad thing, it would even be an adaptation strategy in the face of climate change. Recent studies show that there is a link between rising temperatures and the size of animals. We didn't have much evidence on the subject but it was before 70,000… migratory birds of 52 different species were studied in millimeters from the length of the leg bone, beak and wing to 'to the weight of each individual. Some migrants like the wagtail have lost 2 grams in 40 years!
How does it benefit birds to shrink in hot weather?
Very concretely to save energy, the lighter we are the less we are affected by high heat, this is the principle of thermoregulation, the body will dissipate heat more easily if it weighs less-from there we would observe a lower bird mortality linked to heatstroke, this is also valid for humans who are less able to withstand heatstroke in an overweight situation, except that this rule does not seem to concern us, for the moment the curve of obesity is increasing as much as that of global average temperatures!
This is good news in any case for certain species which would adapt rather quickly to the upheavals of climate change!
We can see the positive and say that some species can adapt at the same rate as the sudden changes in their environment but to what extent and how many species will leave more than feathers if temperatures reach thresholds as much unacceptable than reversible, that is to say beyond two degrees before the end of the century, making adaptation impossible even for the species most capable of absorbing shocks!