the original snake ancestor was a nocturnal, stealth-hunting
1 that had tiny hindlimbs with ankles and toes, according to research published in the open access journal bmc
2 biology. the study, led by yale university, usa,
3 fossils,
4, and
5 from 73 snake and
6 species, and suggests that snakes first evolved on land, not in the sea, which contributes to a longstanding debate. they most likely originated in the warm, forested
7 of the southern hemisphere around 128 million years ago.
snakes show incredible diversity, with over 3,400 living species found in a wide range of habitats, such as land, water and in trees. but little is known about where and when they evolved, and how their original ancestor looked and behaved.
lead author allison hsiang said: "while snake origins have been debated for a long time, this is the first time these hypotheses have been tested
8 using cutting-edge methods. by
9 the genes, fossils and anatomy of 73 different snake and lizard species, both living and extinct, we've managed to generate the first comprehensive
10 of what the ancestral snake was like."
by identifying similarities and differences between species, the team constructed a large family tree and
11 the major characteristics that have played out throughout snake evolutionary history.
their results suggest that snakes originated on land, rather than in water, during the middle early cretaceous period (around 128.5 million years ago), and most likely came from the ancient supercontinent of laurasia. this period coincides with the rapid appearance of many species of mammals and birds on earth.
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