In my Openness book I argue that global warming is not as much of a threat as many claim. One part of my argument is that humans, and non-human life too, is much more adaptable than the environmentalists realize. Songbirds discussed below exemplify the point.
(p. A3) North American songbirds have been shrinking steadily in size over the past 40 years, according to scientists who measured tens of thousands of the feathered creatures from dozens of different species and attributed the changes to rising temperatures.
As the birds’ bodies got smaller, their wings gradually got longer, the scientists said in a paper published Wednesday [Dec. 4, 2019] in the journal Ecology Letters. The longer wings, the researchers said, may help offset the loss of body mass so the birds can fly efficiently on their long migrations.
. . .
Warm-blooded animals are generally larger in cold climates and smaller in warm climates because more compact creatures usually release heat more quickly, according to biologists and ecologists.
Given the well-established link, many scientists had predicted in recent years that global warming would affect the size of many animals. Yet until recently, there wasn’t much evidence of the effect at work during modern warming trends.
The new findings are the latest in a series of technical reports this year that link changes in body size among birds to warmer temperatures around the world.
Last month, researchers in Australia who studied physical changes in 82 songbird species, including honeyeaters, fairy-wrens and thornbills, reported in the Royal Society B journal that birds there have grown smaller due to warming over the last half-century, as the annual mean temperature increased regionally by about 0.012 degrees Celsius. They based their conclusions on an analysis of 12,000 museum specimens.
In March [2019], researchers at the University of Cape Town in South Africa who tracked the weight of a long-tailed songbird common across Africa called the mountain wagtail found the species gradually became lighter between 1976 and 1999, as regional temperatures increased by 0.18 degrees Celsius. They published their findings in the journal Oecologia.
For the full story see:
(Note: bracketed date and year added.)
(Note: the online version of the story has the date December 4, 2019 [sic], and has the title “Songbirds Are Shrinking in Size, Study Finds.”)
My book mentioned above is:
Diamond, Arthur M., Jr. Openness to Creative Destruction: Sustaining Innovative Dynamism. New York: Oxford University Press, 2019.
The academic paper in Ecology Letters, mentioned above, is:
The academic paper in the Royal Society B journal, mentioned above, is:
The academic paper in the Oecologia journal, mentioned above, is: