Wow, birds. It wasn’t enough that most of you can fly and attack from above. Or, that you are descended from theropod (flying) dinosaurs. Or that your entire class is all messed up – what’s up with penguins anyway? Their bird status seems a little weak as far as we’re concerned. Like Pluto, they’re right on the edge, and we all know what happened to Pluto. But now birds, you’ve gone a step too far. Scientists have found shimmering iridescent eggs.
Shimmering iridescent eggs? This feels like some kind of insane advertising campaign. Don’t like the original? Now with colors!
Great Tinamou eggs look a little like Easter eggs, reflecting lovely pastel colors. This differs totally from the actual bird. Sorry Great Tinamou, but you are not one of the more attractive birds.
Maybe that’s why their eggs need to be so awesome? Anywho, this is the first discovery of eggs with iridescent properties. And really, it’s incredibly counter intuitive. Eggs are sought after by predators — just reading Charlotte’s Web illustrates that little factoid. Making the eggs a brightly colored temptation seems to be inviting trouble.
Researchers theorize that the colors perhaps make it easier to differentiate the correct mother of the eggs, since Tinamous hens often lay their eggs in each others clutches. Another theory is that the bright colors essentially blackmail the male birds into “incubation attendance” – basically standing watch over the eggs just like the female birds because of the increased risk of predation. Uh huh.
A more neutral explanation lies in the environment that the birds live in: dense rainforest of both the flooding and non-flooding variety.
As a result of all that water, the thin outermost covering of the egg (called the cuticle) is incredibly smooth and glossy, preventing water from clogging the pores of the egg. That glossy, reflective surface may also act as a solar heat shield. Yep, just like those weird mirrored sunglass things you put in the windshield of your car.
While that may explain the reflective iridescence of the eggs, it’s not the only explanation for the color. When the cuticle is removed, the egg is no longer glossy but it still has distinctive colors. It’s like a double rainbow! Color through reflection and through pigmentation.
Geeze, birds. You already have plumage, wings and a connection to dinosaurs, now you need to make your own Fabergé eggs? A line has been crossed.
Featured Image Credit: Manuel Anastácio