Fewer sunny days and a warming climate are making ladybugs off the coast of the Netherlands turn from black to red. Mammals might adapt to a warming climate by, say, losing fur over generations or developing more sweat glands. Fish might adapt by moving to deeper, cooler water. Ladybugs apparently change color.Different colors reflect different amounts of light. Light that isn’t reflected by a material is absorbed, and the energy of those photons is retained by the material. That energy, in the case of our ladybug friends, becomes heat. Black reflects almost no light, so it retains a whole bunch of heat energy. Which is great in a cold climate, but not so much in the global greenhouse.In the Netherlands, two-spotted ladybugs along the coast have historically been black with red spots; inland, they’re more often red with black spots. In the past few years, however, more and more red guys have been found near the sea, according to a new paper in Heredity. You could look at it as providing your own sunscreen: red reflects, ladybugs stay cool. The difference between red and black in ladybugs is only one protein, so as far as genetic adaptations go, it’s an easy switch.From ScienceNOW:As they continued to catch hundreds of ladybugs every 5 years or so, over 50 generations of ladybugs, they found more of the nonmelanic bugs, even when sampling inland. In 2004, the last year in which the researchers could gather enough ladybugs to see a significant trend, they found that only 20% of the ladybugs in any area were melanic. The trend seemed to fit with temperature data over the period, which showed that the entire area had been consistently warming, the researchers report.It’s a good hypothesis that still needs more research, but the two-spotted ladybug story ends here unfortunately. An invasive species call the Japanese harlequin ladybug, escaped from a greenhouse in Belgium, has made two-spotted ladybugs extremely rare — rare enough that further work on the changing colors of ladybugs in the Netherlands can’t go forward. I suppose you can’t adapt to everything.Reach this writer at michaelb@motherboard.tv.
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