The natural world has lost one of its most preeminent figures this week as Titus, known as the Gorilla King, succumbed to old age and died on September 14, 2009.

Filmmaker Allison Argo shares some thoughts on the making of "Chimpanzees: An Unnatural History."

In 1967, local villagers in Africa's Equitorial Guinea captured a remarkable baby gorilla with a coat of pure white. Watch the full episode online.

(Airs Sunday, June 20) While we are mesmerized by their likeness to our species and we have continually found uses for chimps, we never considered what they wanted or needed.

View additional Web and print resources for NATURE's "Chimpanzees: An Unnatural History."

NATURE interviewed Gloria Grow, the founder of Fauna Foundation, which cares for retired chimps.

Living a life of captivity leaves deep scars and identity crisis -- even in those chimps lucky enough to retire to a sanctuary like Fauna Foundation.

Sharing 99 percent of our DNA, chimps have been used in the study of infectious diseases, gene therapy, vaccine development, reproduction, and anatomy.