Thursday, May 1, 2014
…the blue mystery of “Robin’s eggs/huevos”…!
The great blue mystery of robins’ eggs
Why are robin’s eggs blue?
Ask your own question!
More than 30 years ago, famous bird biologist David Lack wondered the same thing. He noticed that birds nesting on the ground often lay brown or gray eggs that blend in with the surroundings. And birds that lay highly visible white eggs often conceal their nests in a hole. He suggested that the blue eggs of many songbirds might blend in at the bottom of a dark nest that is screened by leaves from above. This could help hide the eggs from predators such as squirrels, ravens, and jays. But, he admitted, blue eggs were the “biggest puzzle.”
Franz Gtmark tried to solve the puzzle by painting quail eggs white, blue, or spotted, then putting them in artificial nests in trees. Predators took all three types equally. So although, in theory, blue eggs in nests might be hard to find, scientists haven’t yet come up with the evidence.
And that’s just one of the mysteries when it comes to the color of eggs. Why are an emu’s eggs dark green like an avocado? Why are a Chilean tinamou’s eggs purplish? I don’t know.
Most birds have pigment glands that deposit colors on the egg as it passes through the oviduct. Usually each bird species has a characteristic egg color.
But in some species, such as the common murre, different females lay eggs with different colors—for example, bright pinkish, creamy or pale blue. Additionally, the eggs can have black, red, or yellowish-brown blotches or squiggles. A murre lays her eggs on a ledge near the eggs of other females. Distinctive eggs may help her recognize which ones are hers. Experiments show that a murre will only accept a new egg if it resembles her own.
OK, but why do the eggs laid by the same American crow look so different from one another—some heavily spotted, others nearly plain? Maybe some day you can help us find out.
…predators take any color eggs…! so why the different colors…?
…We agree that shape has a more better function in eggs, than color…!
…I will guess for you all…! The parents “like” the blue color eggs, and don’t abandon them or eat them up themselves…!
Blue is also a cold soft color…! But will absorb more heat by light, than a white egg that would reflect light more…!
BLUE COULD BE MISTAKEN WITH THE COLOR OF “WATER”…! WHICH COULD BE A BAD MISTAKE FOR A THIRSTY ROBIN…!
I had a pretty face small parrot that would eat up its eggs…!
IF YOU HAVE ANY OTHER REASON, FOR ROBINS “BLUE EGGS”, LET ME KNOW…!
THE ONLY OTHER REASON, OTHER THAN SMALL MUTATIONS, IS THAT THEY WERE DESIGNED LIKE THAT…! But not by the “God of the Bible”, nor did “Mother Nature Evolution” do it either…!