Humans have changed ecosystems more rapidly and extensively than in any comparable period of time in human history, largely to meet rapidly growing demands for food, fresh water, timber, fiber and fuel. This has resulted in a substantial and largely irreversible loss in the diversity of life on Earth.

Great moments in science: Einstein discovers that time is actually money.

The Bluebird of Happiness long absent from his life, Ned is visited by the Chicken of Depression.

Morbid humor is very valid, even healthy, as long as you don't do it gratuitously.

As for the reasons behind my retirement, they mostly center around simple fatigue and a fear that if I continue for many more years my work will begin to suffer, or at the very least ease into the graveyard of mediocre cartoons.

The Bluebird of Happiness long absent from his life, Ned is visited by the Chicken of Depression.

I've always thought the word cow was funny. And cows are sort of tragic figures. Cows blur the line between tragedy and humor.