View More

The human body converts the energy contained in food to mechanical output with an efficiency that may surprise you — it’s that low. What goes on at the gym reflects this. A person dedicated to keeping reasonably physically fit might use a rowing machine, an elliptical trainer, or a stationary bicycle. These machines usually provide readouts that show how much work the user is doing, and how many Calories she is burning. Checking the numbers now and then helps pass the time, and may provide a little reward at the end.Read the rest “The Inefficiency of Humans”

View More

Our bones, teeth and hair carry in them an encrypted GPS log of where we’ve been. If you lived in Seattle through your childhood and moved to Chicago ten years ago, that is indelibly written there. There will also be a record of what you’ve eaten recently. Advances in the science and technology of reading that information are having an impact on forensics, anthropology and agriculture, among other pursuits. At the heart of that technology lies a fundamental property of matter, which is that many of the atoms that make up all of creation come in subtle variations, variations that we are able to detect with great precision.Read the rest “Your travels are Written in your body”