In many branches of science, a good clock can make all the difference. The better we can determine how old things are and when events happened, the better we can put the pieces of history back together. It’s important to know that the universe started 13.73 billion years old, for example, and that the Earth is 4.56 billion years old.

There is no one clock to rule them all, though. Each science requires a clock of its own, and some of them require a whole wall of timepieces. For the universe, we have to use old light to tell time. For the Earth, certain radioactive elements like strontium have ticked away accurately since the planet’s formation. Continue reading “Friday’s Elk: February 25, 2018” →

Some muskoxen weigh over a thousand pounds. They’re hard animals to miss–that is, if you’ve hopped in a snow machine and traveled across an Arctic tundra for a few hours in search of a herd. But to understand muskoxen there’s no alternative but to be where they live. You can’t Google-Earth your way to insight.

This week in the New York Times, I wrote about Joel Berger, a biologist who has spent a lot of time looking at muskoxen over the past decade. Berger’s research has revealed a worrying vulnerability in these polar giants. Climate change may starve pregnant muskoxen mothers. You can read the whole story here. Continue reading “Friday’s Elk January 20, 2018” →