Final answer:
Sahelanthropus tchadensis was discovered in Chad, West Africa, by Michel Brunet's team in 2002 and is regarded as an ancient hominid species that lived around seven million years ago.
Step-by-step explanation:
The geographical area of the discovery of Sahelanthropus tchadensis is Chad in West Africa. This significant paleoanthropological discovery was made by Michel Brunet and his team in 2002. Sahelanthropus tchadensis is considered one of the oldest known hominid species, with an estimated age of nearly seven million years, living around the time that the human lineage diverged from that of chimpanzees. The fossil, nicknamed “Toumai,” exhibits both primitive and evolved characteristics, and its association with the lineage leading to modern humans remains to be fully understood.