The definition of the noosphere as “the sphere of human thought on earth” is woefully anthropocentric. It ignores that fact that our fellow sentient organisms have noospheres of their own. Elephants have their own social networks, maintaining close friendships and extended tribes, and keeping touch over long distances through subsonic rumbles.
If the noosphere can loosely be defined as the interaction and interconnection of conscious minds, then clearly cetaceans, wolves, great apes, elephants, and many species of birds have their own forms of a noosphere. Granted, these noospheres are not as large and complex as ours. Humans have telecommunications, the biggest brain-to-body ratio on earth, and the force of numbers – 7 billion of us, versus a few tens of thousands for African elephants, and a few hundred thousand for chimpanzees.