That humans evolved as a result of a move from forests to more open plains is still
the prevailing paradigm in anthropology, and researchers often assume that this transition
influenced the origins of human bipedalism, omnivory, tool use, large brains, and even
speech. Here, we argue that there are no scientific grounds on which to base such a
hypothesis. While we agree that Homo may have evolved in more open (tree-poor)
habitats than other apes (which could account for our relatively poor climbing skills), the
suggestion that humans shifted to drier habitats away from water is, according to our
research, unproven. We propose instead a more parsimonious model compatible with all
known data and corroborated by a number of independent sources of evidence.
Comparisons of the locomotor styles and nutritional requirements of extant species
and anatomical comparisons of fossil and extant species including Homo sapiens,
especially in combination with palaeoecological data, strongly suggest that early Homo
evolved at the water’s edge (whether in savannahs or elsewhere) where resources
essential for brain growth were both abundant and easily procurable by a thick-enameled
tool-using omnivorous hominid.
http://users.ugent.be/~mvaneech/Verhaegen%20et%20al.%202007.%20Econiche%20of%20Homo.pdf
