The National Center For Science Education (now at its new ncse.com address) is offering a free pdf of a chapter from my book, The Tangled Bank: An Introduction to Evolution. The chapter, called “Radiations and Extinctions,” is about the two sides of biodiversity. First I look at how biodiversity rises over time (the ascent of the animal kingdom, for example, and the wild exuberance of insects). Then I look at how biodiversity falls, thanks to background extinctions and mass extinctions. And then I take a look forward and see ominous signs for biodiversity’s future, such as corroding oceans.

If you like what you read, you can find out more about The Tangled Bank here. Or you can cut to the chase and get the whole book–as a holiday gift for yourself, or for that special someone who keeps asking you how we can be descended from monkeys if there are still monkeys around.

Originally published December 15, 2009. Copyright 2009 Carl Zimmer.

This spring I blogged about some marvelous videos made by scientists at Brown University in their quest to understand how bats manage to be bats. Turning your hands into membrane-lined wings makes for some awkward trade-offs. Moving around on the ground, for example, gets to be a special challenge. Bats have not simply evolved a single solution to these trade-offs, however. Instead, they’ve explored lots of different compromises. While many bats can only creep awkwardly on the ground, for example, vampire bats can actually gallop.

Continue reading “Spiderman’s Bats”

Carl Buell, who illustrated many lovely critters for my new book The Tangled Bank, has been adding some new paintings to his Flickr stream. Here’s his holiday ground sloth.

In the caption, he writes: “I’ve certainly drawn and painted enough of them over the past 15 years. Ground sloths are a favorite subject. Too big to hide from the weather, this big guy just hunkered down and slept through the storm. It’s hard to imagine these guys in snow, but Megalonyx ranged as far north as Alaska. Another Card idea that never got off the ground.”

Card or not, I’m glad he’s sharing his handiwork.

Originally published December 12, 2009. Copyright 2009 Carl Zimmer.