Chip Brown:

In the past some anthropologists have fetishized cultural purity, fretting over the introduction of modern technology. But cultures evolve opportunistically like species -- the Plains Indians of North America picked up their iconic horses from the Spanish -- and strong traditional cultures will privilege themselves, making the accommodations they think will ensure their futures. We can question whether a man dressed in a parrot feather headdress and penis sheath is more valuable than one in a Batman T-shirt and gym shorts. But who can be blind to their knowledge of forest plants and animals or to the preeminent values of clean water, untainted air, and the genetic and cultural treasure of diversity itself?

Samira Kawash:

In the 1960s and before, it was totally fine to give out something you'd made yourself. But once people got it in their heads that maniacs were out there trying to kill their children with Halloween treats, everything homemade was suspect. After all, you didn't know whose hands had touched that cookie and what scary ingredients might be hidden under the chocolate chips. Same for unwrapped candies and off-brand candies: If it wasn't sealed in a recognizable, major brand factory label, then it was guilty until proven innocent. National advertised candy brands were familiar and trusted, unlike that spooky neighbor who just might be an axe murderer. It's one of the huge successes of processed food marketing, to make us trust and feel good about the factory food, and to distrust and denigrate the homemade and the neighborly.

Sasha Chapman:

Now, you might say that anyone who eats chicken sashimi is engaging in high-risk behaviour; but eating is always an intimate act, and, like most acts of intimacy, it requires you to trust your partner. Somebody -- more often than not a stranger -- has created something that will end up inside you, part of you.

It's easier not to think about where our food comes from, or the risks it carries.

Tim McDonnell:

In the last 40 years, the Arctic has warmed by about 3.5 degrees Fahrenheit, more than twice the overall global rise in that same period. Already grizzly bears are tromping into polar bear territory while fish like cod and salmon are leaving their historic haunts to follow warming waters north. One tangible result of the migration, scientists report, is that animals will learn to live with new neighbors. But polar biologists worry that animals could get a little too friendly with each other.

Julie Cart:

The U.S. Fish and Wildlife Service is weighing an environmental group's request to set aside 110,000 square miles for grizzly bears in California, Arizona, New Mexico, Utah and Colorado.

Ian Chant:

At its heart, breeding animals represents the industrialization of mutations.

Sujata Gupta:

Whereas in 1957 a typical dairy cow produced between 500 and 600 pounds of milk over a post-natal lactation period, she now produces close to 20,000 pounds. Consequently, today's burnt-out dairy cow survives just over two lactations, compared to between 10 and 20 lactations in earlier years.