Elephant social rules are very complex. Females dwell in tightly bonded families that stay together for life, and males live a largely solitary existence.

Echo, an African elephant, was a true matriarch, a wise and experienced mother who guided and protected her family for many years.

Elephants rely on a complex communication system to sustain their clan-based society. At the root of it is a common language.

Joy, anger, grief, love -- all reside within elephants. Through years of research, scientists have found that elephants are capable of complex thought and deep feeling.

Explore the photographs and artwork of naturalist Ernest Thompson Seton.

View photos of Thea Litschka-Koen and her husband, Clifton, as they try to save lives and change attitudes about the black mamba, Africa's deadliest snake.

Go behind the scenes of Cuba: The Accidental Eden to see how they get around the island and capture aerial and ocean photography.

Can Cuba build a bridge to its environmental future?

Molecular biologist Peter Savolainen of the Royal Institute of Technology in Stockholm, Sweden, and his colleagues have studied the origins of domestic dogs using hair samples and mitochondrial DNA.