Claim: Many zoos contribute to animal suffering.

Claim: Many zoos today provide humane settings for animals.

Support: Gorillas used to die in zoos, but they now thrive in well-designed exhibits.

Many zoo enclosures both new and old are too small.

Support: More than 90 % of mammals in accredited zoos were born in zoos, not the wild.

Support: Zoos often ignore the natural biology and behavior of animals and create exhibits that are attractive to visitors.

Support: The holding areas, where many animals spend a lot of time, resemble prisons.

Support: Gorillas live longer lives in zoos today than they do in the wild.

The article by this writer discusses a wider range of zoos.

The article by this author discusses only accredited zoos in depth.

"...vast numbers of zoo animals continue to endure lives of misery and deprivation.l" -Laidlaw

"Only 16 species have established self-sustaining populations in the wild as a result of captive-breeding efforts..."-Laidlaw

"So long as wild animals are kept in captivity, they ought to be treated humanely."-Laidlaw

"Even as late as the 1960s and '70s, most zoo gorillas were kept singly or in pairs in small, sterile concrete and tile cages and fed inappropriate foods." -Hutchins

"In 2002, over 140 million people visited AZA zoos and aquariums..." -Hutchins