A 120-million-year-old fossil of a pregnant lizard has been found in China: BBC reported Thursday. The fossil is a complete 30 cm lizard with over a dozen embryos in its body.
Researchers from University College London, who studied the fossil, say it was just days from giving birth when it died and was buried during the Cretaceous period. The findings were published in the journal Naturwissenschaften. The fossil is interesting to scientists because it is a reptile that produced live young rather than laying eggs.
Only 20 percent of living lizards and snakes produce live young, and this shows it is an ancient, if unusual, trait. “I didn’t think much of the fossil when I first saw it,” BBC quoted Susan Evans, joint lead author of the paper, as saying.
But when her colleague, Yuan Wang, from the Chinese Academy of Sciences, examined the fossil he spotted the tiny remains of at least 15 almost fully developed embryos inside it, it said. The fossil is so well preserved that the minuscule teeth of the developing young are visible on very close inspection.
Scientists thought that, in extinct reptiles, live birth was restricted to aquatic species, such as marine ichthyosaurs. These creatures would have been able to move through water with relative ease, even when heavily pregnant. The fossilized mother lizard, found in northeastern China, has been identified as a specimen of Yabeinosaurus, a large, slow-growing and relatively primitive lizard. (IANS) link.1, Link2