The spectrum of colors seen on modern bird eggs likely evolved from dinosaurs, a new study suggests.
According to a new study published Wednesday in the journal Nature, non-bird dinosaurs laid eggs in open or partially open nests. Modern bird eggs, even those that are spotted or speckled, are primarily based on two color pigments: red and blue.
The research suggests with the open nesting practices of dinosaurs, white eggs were more likely to fall victim to predators. So colored eggs could blend in better with the nest, giving them a better chance for survival.
"This completely changes our understanding of how egg colors evolved," said Jasmina Wiemann, Yale paleontologist and the study's lead author. "For two centuries, ornithologists assumed that egg color appeared in modern birds' eggs multiple times, independently."
Using a non-destructive laser microspectroscopy, Wiemann and a team of researchers inspected 18 fossilized dinosaur eggshells for the existence of two eggshell pigments, to see how far in colored eggs go in history.
"Colored eggs have been considered a unique bird characteristic for over a century. Like feathers and wishbones, we now know that egg color evolved in their dinosaur predecessors long before birds appeared," said Mark Norell, the Macaulay Curator of Paleontology at the American Museum of Natural History and co-author of the study.
Although the team didn't find any pigment in two modern bird ancestors, the triceratops and the long-necked diplodocus, they did come up with pigment in the Eumaniraptoran dinosaur eggshells, NPR News reported. These were members of the small, meat-eating group that included the velociraptor, made famous in the Jurassic Park movies.
"We infer that egg color co-evolved with open nesting habits in dinosaurs," Wiemann said. "Once dinosaurs started to build open nests, exposure of the eggs to visually hunting predators and even nesting parasites favored the evolution of camouflaging egg colors, and individually recognizable patterns of spots and speckles."
By Tauren Dyson
Fuente: www.upi.com
