Hummingbirds might be beautiful, but their wings beat so quickly we have to check out still-frame photos to really appreciate how unique and lovely their coloring is.
Scientists are happy that technology exists, though, because otherwise they may never have stumbled across the mystery that is these hybrid hummingbirds.
Image Credit: iStock
Some species of hummingbirds are purple, while others are a bright turquoise or sport a shiny pink throat. Biologists have many theories on the roles of the particular colors, and more than one of them is probably accurate, according to evolutionary biologist Chad Eliason of Chicago’s Field Museum.
“I look out across the bird world for interesting colors and try to understand the physics of how those colors are being produced. With that knowledge, I could understand why some of these colors might be evolving more rapidly or why there might be more colorful species in certain areas of the world.”
When scientists spotted a gold throat on what they first thought was a pink-throated Heliodoxa hummingbird, they thought it was a completely new species – only to later learn it was actually a hybrid of two pink-throated species instead.
They describe their find – the first ever encountered – in Royal Society Open Science.
“I looked at the bird and said to myself, ‘This thing doesn’t look like anything else.’ My first thought was, it was a new species.”
When they checked the DNA results, though, they found mitochondrial DNA from one pink-throated species, the H. branickii, but nuclear DNA from both that bird and a genetic cousin, the H. gularis.
Image Credit: Kate Golembiewski, Field Museum
The bird in question was not half of one and half of the other, though, leading experts to believe there was a half-and-half bird somewhere in its ancestry, but that subsequent generations had mated and reproduced with H. branickii exclusively.
How did two pink-throated birds create a gold-throated offspring?
It’s kind of complicated, and is determined by pigments like carotenoids (red and yellow) and melanin (black), which give feathers their base colors. It’s the structure of the feather’s cells and the way they reflect light that makes them appear to shift in color.
“We knew coming into this that hummingbirds had the most complex melanin structures or the iridescent structures of all birds.”
They used an electron microscope to examine the structure of the feathers on a subcellular level, measuring how light bounces off them, and found subtle differences in the parent’s coloring.
“There’s more than one way to make magenta with iridescence. The parent species each have their own way of making magenta, which is, I think, why you can have this nonlinear or surprising outcome when you mix together those two recipes for producing a feather color.”
Some hybrids remain completely unique, but others eventually are labeled a new species. Not knowing how common this particular combination is, scientists are unable to determine which way this one might go at the moment.
They did calculate that it would likely take between 6 and 10 million years for this particular shift in color to take place, which gives you some context – even if 6 to 10 million years is fast where evolution is concerned.
Photo Credit: iStock
Researchers do plan to continue studying the bird, using modern genetics and gene-sequences tools to determine how many generations strange changes like this one take to occur.
As for me, I’ll be over here enjoying the pretty pictures.
