A paleontological surprise may be hiding in your Easter basket. New research indicates that some grocery-store candy eggs are remarkably similar in shape to a newly discovered dinosaur egg, instead of the traditional chicken egg.
"Where do Easter eggs come from? At face value this is a simple question, but any parent trying to provide an answer this Easter might struggle to come up with a satisfactory response," Mark Purnell, a researcher at the University of Leicester, said in a statement. "According to many, the eggs are delivered by the Easter Bunny, but that doesn't really address the question: Where does the Easter Bunny get them from?"
The research started as an analysis of a newly discovered 70-million-year-old egg, one that would've been laid by a mama dinosaur during the Late Cretaceous when Tyrannosaurus rex walked the earth. The researchers named the new species, whose egg was discovered in the Pyrenees, Sankofa pyrenaica. (Sankofa is an Ashanti word meaning "learning from the past.")
To figure out if the egg belonged to an ancient bird or its dinosaur relatives, the team compared the shapes of eggs from birds and dinosaurs. They came up with a mathematical formula to determine and describe all possible egg shapes; next they plotted real eggs, based on size and shape, into this "egg morphospace."
"We found that different species have different-shaped eggs, and that the eggs of dinosaurs are not the same shape as the eggs of birds," study researcher Enric Vicens, of the Universitat Autonoma of Barcelona, in Spain, said in a statement.
In general, birds' eggs tend to be more rounded than dinosaur eggs, which are more elongated, the researchers found. Dinosaur eggs "also tend to be more symmetrical with less distinction between the blunt and the more pointed end," Vicens said.
They found the new Sankofa egg fell somewhere between dinosaur eggs and bird eggs. It's oval-shaped than teardrop-shaped. There are no other eggs like it, the researchers said.
A second, smaller study compared the sizes and shapes of these bird and dinosaur eggs with that of eggs sold in stores in the United Kingdom. They found that dinosaur eggs are closely related, in shape, to some of the modern Easter eggs in the store. The Sankofa egg looks a lot like the Lindor Easter egg chocolate, and less like the Cadbury Creme Egg, which is shaped more like a chicken egg.
"Many of the smaller eggs to be found commonly on the UK High Street are very similar in shape to hen's eggs, providing strong clues to their original source. Others are more similar in shape to condor eggs," Purnell said. "Perhaps more surprisingly, a few eggs are closer in shape to those of dinosaurs, with one in particular being the same shape as the 70-million-year-old dinosaur egg."
The study was published in the March 2012 issue of the journal Palaeontology.
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