Tag: Sean Carroll

Evolution and geology

I just finished reading Sean Carroll’s book The Making of the Fittest. Subtitled “DNA and the Ultimate Forensic Record of Evolution”, it’s the follow-on book to Endless Forms Most Beautiful. In this book Carroll devotes several chapters to demonstrating how, against our natural intuition, there really is enough time (given a few hundred million years) for DNA to mutate bit by bit and still make amazing new structures like eyeballs, wings, and that pink dangly thing that hangs at the back of your mouth.

Carroll also points out that while almost everything is in flux, genetically speaking, there are some stretches of DNA so crucial to life that they never change. Which is to say, they can’t change because any variation would be fatal. Here, for example, is a six amino acid stretch that has been found in every single living thing: KNMITG. It’s an immortal sequence, unvarying across more than a billion years.

The last chapter deals with the controversies associated with teaching evolutionary theory in public schools. This is well-traveled ground, but it got me thinking about how much the opponents of evolution focus on man, monkeys, and biology class. But shouldn’t they be attacking geology too? Some of them do, insisting, for example, that the Grand Canyon formed during Noah’s flood. But it seems that a serious and consistent creationist ought to stick those little “this is only a theory” labels in every science book on the shelf. The astronomy book, the geology book, the physics book, they should all be thrown out the window along with The Origin of Species. Why is poor old Darwin always taking the heat?

The big brain

I was recently reading Sean Carroll’s excellent book on evolutionary developmental biology, Endless Forms Most Beautiful, in which he says that “brain size [in humans] roughly doubled in a million years.” This was a dramatic (and expensive) departure in the brainweight-to-bodyweight ratio compared to all other mammals. Carroll goes on to say:

The brain is a very expensive organ in terms of energy consumpution, drawing up to 25 percent of an adult human’s energy (and 60 percent of an infant’s).

Who knew the brain was such a hog? You can rest your legs and unshoulder your weary load, but your brain keeps drawing current rain or shine. And a good thing too. An evolutionary stockbroker might describe the relationship between the brain and the evolutionary fate of Homo sapiens as this: an expensive investment, but ultimately worthwhile.

These words were in my head as I recalled some articles I was reading about the growing electrical appetite of data centers. It turns out that data centers and server farms are sprouting like mushrooms along the Columbia River in Washington and Oregon. Why? Because that’s where the cheap hydroelectric power is. These giant computing centers, erected in rapid succession by Google, Yahoo, Microsoft, and others are hot, hungry, and growing fast. The electrical power consumed by computers has become one of the most significant costs of a modern corporation, particularly since it has the knock-on expense of driving cooling costs too. Electrical companies joke about giving away computers and making up the cost on juice.

Who knew the computer was such a hog? We can regulate our trucks and trade in the Hummer for a Prius, but the great Google brain keeps drawing current rain or shine. Every day, as we commune by keyboard with the net, banging out our neuron’s part, the network is evolving.

I’m guessing it’s an expensive investment, but ultimately worthwhile.