Beyond three billion years ago, the fossil record of life on Earth gets very patchy. At 3.4 billion years ago, there’s fairly good evidence of mats of microbes. At 3.5 billion years, there are little globules that have been proposed to be bacteria but which some researchers consider just blogs blobs of minerals. Earlier still there are shadowy isotopic hints–ratios of light and heavy carbon atoms that seem biological rather than volcanic–dating back as far as 3.8 billion years. These, too, are the subject of great debate. And before that, nothing. Seven hundred million years of nothing.

Continue reading “Life On Earth: A Losing Game of Whack-A-Mole?”

Yale Environment 360, May 20, 2009

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The earth’s climate has, of course, fluctuated frequently — and at times wildly — over hundreds of millions of years, long before humans began pouring heat-trapping gases into the atmosphere. So why the concern over the current surge of warming, brought about largely by human activity? Anthony Barnosky, a University of California, Berkeley, scientist who has studied previous eras of climate change, succinctly sums up the problem: Too much warming, too fast.

Continue reading “Previous Eras of Warming Hold Warnings for Our Age”

Today I’ve got an interview posted over at Yale Environment 360 with Tony Barnosky, a paleontologist who’s just written a very interesting book called Heatstroke: Nature in an Age of Global Warming. He gazes into a fossiliferous crystal ball to get an idea of what global warming will do to the world’s biodiversity. Short answer: it won’t be pretty.

Continue reading “Let Us Not Forget The Books: I Need Your Vote Again”

If the world goes crazy for a lovely fossil, that’s fine with me. But if that fossil releases some kind of mysterious brain ray that makes people say crazy things and write lazy articles, a serious swarm of flies ends up in my ointment.

Continue reading “Darwinius: It delivers a pizza, and it lengthens, and it strengthens, and it finds that slipper that’s been at large under the chaise lounge for several weeks…”

Readers of the Loom may be familiar with the work of Bryan Fry, who studies the evolution of snake venom. (See these two previous posts on his work.) I’ve got an article in tomorrow’s New York Times about his latest paper, to be published this week in the Proceedings of the National Academy of Sciences. In it, Fry and a big team of collaborators argue that Komodo dragons, the biggest lizards on Earth, are venomous. (There wasn’t room in the story to describe their argument that an extinct relative of Komodos that measured 21 feet long, was venomous too.) Provocative stuff, to be sure, and certainly not universally embraced by other researchers. I got some highly spicy quotes from critics. Check it out.

(PS: When the paper is put online this week, you’ll be able find it here: http://www.pnas.org/lookup/doi/10.1073/pnas.0810883106 )

[Image from Wikipedia]

Originally published May 18, 2009. Copyright 2009 Carl Zimmer.