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Animals’ body sizes shrinking from climate change, study finds, based on a group of wagtails?

Another climate classic today: Animals’ body sizes shrinking from climate change, study finds
by University of Cape Town

Nice theory if you can get funding for it:

“All else being equal, larger animals can tolerate cold conditions better than smaller animals, so one could expect that a warming  is relatively more advantageous for smaller animals,” said Professor Altwegg.

There are 8.7 million species on Earth and this is based on “one” of them:

To investigate this idea and whether it could be true, the research team looked at a group of wagtails living along the Palmiet River.

It’s “a” group — just the one — and a temperature change of less than one fifth of a degree over 23 years:

Based on data from a local weather station near the Palmiet River, the researchers knew that temperatures in the area had increased by 0.18 °C. But they didn’t know how this had affected the birds’ size.

What they found supports the idea that  can shrink Earth’s animals.

“Supports” the idea? The study’s big achievement was only that it didn’t extinguish the idea at the “back of envelope” stage…

Their results showed that as temperature increased along the Palmiet River, the mountain wagtails living there had become lighter. Specifically, they found lighter individuals were replacing heavier ones in the population and that they survived better under high temperatures. This indicated that an evolutionary pressure was acting on the birds to become lighter.

Or maybe food, predators, fertility, rainfall, and disease were more important than 0.18 degrees C which may or may not be larger than the error bars of South African meteorology. Who knows. Australian meteorology has larger “adjustment bars” than this.

But this is definitely evolution. Look closely and we can see evidence that smaller minded researchers are outcompeting larger ones.

This appears to occur in every soft left environment there is, no matter what the climate.

REFERENCE. Seriously?

Jorinde Prokosch et al. Are animals shrinking due to climate change? Temperature-mediated selection on body mass in mountain wagtails, Oecologia (2019). DOI: 10.1007/s00442-019-04368-2

(What are the odds this is pure spoof? I mean, a bunch of wagtails….  fergoodnesssake– Jo)

h/t oldbrew in a comment somewhere at Tallblokes.

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