Stink bug moms appear to carefully choose the color of their eggs.
A female Podisus maculiventris stink bug can lay eggs in a range of colors from pale yellow to black. P. maculiventris moms control the color of the eggs they lay, seemingly pairing darker eggs with darker surfaces, researchers report July 23 in Current Biology.
Eggs laid on the top surface of leaves were over two times darker, on average, than those laid on a leaf’s pale, top-lit underside, the researchers report. They found that darker eggs protected developing stink bugs from the sun’s harmful ultraviolet rays, which are probably most intense on a leaf’s sun-exposed top surface. P. maculiventris seems to visually assess a surface to determine how dark its eggs should be. It’s still a mystery what chemical the stink bugs use to darken their eggs; the scientists were surprised to discover that the eggs weren’t colored with the compound melanin, which produces most dark color in insects.
The scientists say this is the first time an animal has been shown to control the color of its eggs at will.