As an environmental scientist, I think our first need is to feed and shelter and nurture. That has always required the exploitation of plant life, and it always will.

Your bones are not just made of the last meal you had, but the meals that you've had across many years. By looking at the composition of those teeth, researchers can say that something was a large component of the diet. This tells us a lot about how hominins lived and what they ate.

One cannot rule out a blizzard in Minnesota after Labor Day, and so when I travel for Thanksgiving or any time in the fall, I am careful to fly into Des Moines instead of Minneapolis and then drive the 200 miles north to my hometown.

There is nothing in the world more perfect than a slide rule. Its burnished aluminum feels cool against your lips, and if you hold it level to the light you can see God's most perfect right angle in each of its corners.

One cannot rule out a blizzard in Minnesota after Labor Day, and so when I travel for Thanksgiving or any time in the fall, I am careful to fly into Des Moines instead of Minneapolis and then drive the 200 miles north to my hometown.