I guess it’s only appropriate that the week of Darwin’s birthday is seeing a bunch of new reports about evolutionary transitions. On Monday there was news about how ancient whales with teeth turned into whales with baleen–thanks to the discovery of a fossil of an ancient whale that appears to have had both teeth and baleen. Today’s news takes us from the sea to the trees–the fossil of a primitive bat. The transition that the ancestors of bats made from scampering shrew-like mammals to masterful flyers has remained particularly mysterious. Today’s new fossil lets us look back further than ever into this transition.
It’s time to add a new chapter to the Whale Chronicles….
…more below the fold…
Evidence from both DNA and fossils agree that whales evolved from hoofed mammals on land. At first they may have been occasional swimmers, only later evolving into meat-eaters hunting for prey in the water. Between about 50 and 40 million years ago, they became increasingly adapted to the sea. Paleontologists have found fossils of dozens of species of early whales documenting this transition.
Why are modern families so small? Could it have something in common with peacock tails? A fascinating essay in the new issue of Science is the basis of my newest column for Wired. And man oh man, are the commenters freaking out. Judge for yourself.
The Natural History of the Only Child
Originally published February 8, 2008. Copyright 2008 Carl Zimmer.
WIRED, February 7, 2008
Modern life means small families. Starting about two centuries ago, families in Western Europe began to shrink, and then – country by country, continent by continent – the rest of the world followed suit. The trend is so big that it may rein in the world population’s exponential growth, perhaps even causing it to stop growing altogether over the next century.
But exactly why families are shrinking is a mystery. Rising living standards seem to have something to do with it. It’s certainly true that as living standards rose in England – as children died less from diseases, as the country overall became richer – the size of the English family shrank.
I’ve got some more information about my upcoming talks. On February 27, I’ll be in Ottawa, delivering the Discovery Lecture at Carleton University. It will be called “The Darwin Beat: Dispatches from the Frontiers of Evolution.” Here’s the link to the lecture page.
More updates to come–I’ll post them here, over at carlzimmer.com, and on Facebook.
Update–Talk link fixed…
Originally published February 5, 2008. Copyright 2008 Carl Zimmer.