Five years ago, just before Thanksgiving, I was sitting outside in back of my little house at the edge of the woods. A flock of wild turkeys were pecking at the grass, pushing the leaves aside to find food, cautiously aware of me but not running away. Their gait, like that of most large fowl, seemed both ungainly and stately. As I watched, the two males moved slowly to the front of the flock between me and the smaller females. They stopped eating, fanned out their tails, and paraded about, watchfully. The females continued to eat, and would stop to look up at me or to look over at each other. When one of them strayed a bit far, the others called her back. Some were eating less, accompanying the others and grooming them occasionally. Awkwardness aside, bald head, reptile faces and all, they had me entranced. I could not stop watching them.

Later that day, I went to the store to get everything I needed for Thanksgiving dinner. In the meat cases, hundreds of neatly wrapped turkey carcasses, frozen in several bins, fresh in a few more. I already felt a strong sense of resistance to what I was about to do. But tradition seemed like it would prevail. I picked up one of the fresh turkeys by its nylon mesh handle, and realized that it was soaked in a cold, bloody juice. I put the carcass back down, wiped my pink-stained hands on my pants, and walked out of the store without buying anything.

When I got back home, I went straight to the basement, took off my jeans, and washed them. After the wash was done, I took them out of the machine, and threw them in the garbage. My road to Damascus was paved with beaks, blood, and offal. I have not eaten meat since.

But one by one, the berms we’ve built between ourselves and the beasts are being washed away. Humans are the only animals that use tools, we used to say. But what about the birds and apes that we now know do as well? Humans are the only ones who are empathic and generous, then. But what about the monkeys that practice charity and the elephants that mourn their dead? Humans are the only ones who experience joy and a knowledge of the future. But what about the U.K. study just last month showing that pigs raised in comfortable environments exhibit optimism, moving expectantly toward a new sound instead of retreating warily from it? And as for humans as the only beasts with language? …

All of that is forcing us to look at animals in a new way. With his 1975 book Animal Liberation, bioethicist Peter Singer of Princeton University launched what became known as the animal-rights movement. The ability to suffer, he argued, is a great cross-species leveler, and we should not inflict pain on or cause fear in an animal that we wouldn’t want to experience ourselves. This idea has never met with universal agreement, but new studies are giving it more legitimacy than ever. It’s not enough to study an animal’s brain, scientists now say; we need to know its mind.

Jeffrey Kluger, Inside the Minds of Animals, TIME, August 5, 2010