Human waterside evolution is
-less about becoming aquatically adapted by gradually wading deeper & deeper,
than about aquarboreal hominids in densely vegetated swamp or mangrove forests descending from the trees into the water below,

-not about why Homo & Pan split,
but about what happened afterthe split,

- less about ‘aquatic apes’ or even or even australopiths than about archaic
Homo (erectus-like fossils more than Neanderthals?),

- not about what happened 10 or 5 Ma,
but about what happened lessthan 2 Ma (Ice Ages) when Homo
populations spread along the coasts to England, the Cape & Flores,
- less about how humans today behave in water
than about the differences between erectus & sapiens
(in my 1996 paper, erectus differed from sapiens almost as much as it did from africanus,

- less about bipedalism or even bipedal wading (except <200 ka),
and less about surface-swimming,
than about slow & shallow diving (their food was at the bottom)

- less about what happened in Africa or the Rift Valley
than about what happened on the Indian Ocean or Mediterranean shores,

- less about out of or into Africa or Asia scenarios
than about coastal diaspora
(e.g. on both the African & the Asian side of the Red Sea),

- less about a riverine evolution in fresh-water
than about a coastal (& perhaps later also riverine) life,

- not in the 1st place about an isolated evolution on Danakil or other islands, but about alittoral & estuarine life on African & Eurasian coasts & estuaries (incl.islands?) during most of the Pleistocene,

- not about anthropocentric views (incl. just-so explanations for "unique" human features (e.g. bipedalism for wading, SC fat for surface-swimming),
but about a comparative analysis of our features
(e.g. the combination of bipedalism + vertical spine is only seen in humans & penguins on land),

- not about sudden mutations, saltations or evolutionary jumps from ape- to human-like,
but about a very gradual evolution in small steps:
horizontal arboreal > above-branchaquarboreal > below-branch vertical aquarboreal > littoral > vertical wading > bipedal walking),

- less about the hominid fossil record
than about our embryological, anatomical & physiological "scars of evolution" (Elaine Morgan: "the remnants of the past that don’t make
sense in present terms
–
the useless, the odd, the peculiar, the incongruous
–
are the signs of
history’
(Stephen Gould)