Patrick Pleul / EPA

The inability to catch small prey, such as wild rabbits, may have contributed to Neanderthal extinction.

Neanderthals were big-game hunters who feasted on mammoth and rhino but didn’t or couldn’t eat smaller, leaner meat. Their picky diet — or limited hunting skills — could have made them vulnerable when mammal populations shrank and their favorite dinner became harder to find.

A broad survey of animal remains recorded at early human and Neanderthal sites across Spain, Portugal and France gives us new insight as to what humans and Neanderthals ate. One trend stuck out to scientists who assembled the data: Rabbit remains became much more popular at human sites just about the time that Neanderthals disappeared, about 30,000 years ago.

 Given how common bunnies would have been in that area, the trend hints that Neanderthals did not adapt their diet to include them. After all, the evidence suggests, early humans seem to have made the switch.

There’s no data to explain this trend, but there are theories. Neanderthals may have avoided rabbit dinners because they lacked the technology to catch them, says John Stewart, who studies fossil records and ancient climate at Bournemouth University.

“With modern humans, you see technology that allows them to catch smaller or faster-moving prey,” Stewart told NBC News. That  leads to the “strong possibility” that humans were more efficient than Neanderthals at catching smaller but faster animals. Stewart and his collaborators explain their findings in a paper in the Journal of Human Evolution.

Of course, Neanderthals didn’t just live in Iberia. And in n other parts of the world, there’s evidence to show that they were catching seals and fish and mussels, and even birds.

But Stewart believes that the rabbit diet story is an indication of challenges Neanderthals faced all over the world. “I think the rabbit was just a symptom [of their extinction] rather than the cause,” Stewart says. “Neanderthals were more vulnerable because they had less tricks up their sleeve, less breadth of possibilities.”

More about Neanderthal histories: 

• Neanderthal baby spawns viral video
• The real question: Who didn't have sex with the Neanderthals?
• Here's why creating a Neanderthal clone is a bad idea

Via New Scientist

Nidhi Subbaraman writes about science and technology. Follow on Twitter, Google+. 

You know a story has gone viral when the gang at Taiwan's Next Media Animation makes fun of it — and such is the case with Harvard geneticist George Church's recent comments about the prospects for cloning a Neanderthal baby.

The German magazine Der Spiegel's interview with Church was misconstrued in some quarters as suggesting that the scientist himself was looking for a surrogate mother willing to carry a cloned Neanderthal embryo. In his book "Regenesis," Church says such a scenario is getting closer to the point of possibility. But he's definitely not planning to do the experiment himself. This week, he told the Boston Herald that his original point was lost in translation.

Church and his colleagues are working on a wide array of genetic-engineering technologies, including techniques that could semi-automate the process of producing stem cell lines with artificially added genetic tweaks. Someday, that procedure could give humans new traits, such as enhanced immunity to disease, or enhancements in strength or intelligence. The Neanderthal genome could point the way to such genetic novelties. But if you're looking for a Neanderthal pregnancy, don't bother looking in Church's direction. Instead, have a look at NMA's cartoon — and have yourself a laugh.

More about future evolution:

• Why a Neanderthal clone is such a bad idea
• How synthetic biology will change us
• Human evolution at the crossroads

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.