Mark Witton/University of Portsmouth

Mark Witton/University of Portsmouth

Jan. 20, 2011 -- The discovery of a fossilized pterodactyl mother alongside its egg offers new clues about these flying reptiles, which lived during the Dinosaur Era between 220 million and 65 million years ago.

Dating back to around 160 million years ago, the fossils were discovered in China and provide the first direct evidence of gender in these extinct reptiles.

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The illustration above shows the distinction between the sexes among pterodactyls.

The pterodactyl with the brilliantly colored crest was the male. Scientists have longed wondered why these animals and other pterosaurs had crests. Now, they have an answer: The crests were likely used in displays by males to attract a mate.

Females also had wider hips than their male counterparts, likely to facilitate egg-laying.

Lü Junchang/Institute of Geology, Beijing

Found in the Jurassic rocks of Liaoning Province in northeast China, the fossils reveal that Mrs. T met a tragic end.

Just as she was about to lay her egg, this pterodactyl was killed in an accident resulting from some kind of natural calamity. A storm or possibly a volcanic eruption, which were common in China around that period, appears to be the likely culprit.

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And there's more...

Lü Junchang/Institute of Geology, Beijing

Analysis of the egg, seen above, reveals that reproductive strategies employed by these prehistoric fliers more closely resemble those of crocodiles and other reptiles rather than birds.

The egg is small relative to the size of the pterosaur. The egg shell is also soft, suggesting pterodactyls buried their eggs like modern-day reptiles, leaving their young to absorb nutrients from the ground.

Today's birds, by contrast, lay eggs that are much larger in proportion. They are also rigid since they contain all the nutrients a growing bird needs.

The research was published in the latest edition of the journal Science.