re: #119 chadu

Heh. Several of the “digging deeper” readings were chapters from Lewin & Foley’s textbook “Principles of Human Evolution” 2nd edition. I was impressed enough I bought myself a copy from Amazon (not too bad used). This is their take on the topic:

The issue: the idea that human evolution was
triggered by an aquatic phase is widely supported
and discussed outside the mainstream of
paleoanthropology, but is dismissed by most
scientists working in the field. How do we
determine what models are reasonable and
plausible, and which ones are worthy of serious
scientific study?

Paleoanthropology has a reputation for
controversies and arguments, with major
disagreements about who is who, and who
is related to whom, among the fossil
hominins. However, although there is
considerable debate about the details, there
is nonetheless remarkable consensus about
the major aspects of human evolution -
that our ancestors were derived from a
population of African apes, adapting
in increasingly open and savannah
environments to the changing conditions.
Most features, especially bipedalism, are
seen as related to this change.

There is, though, a vociferous minority
on the margins of the discipline who argue
something completely different: that the
hominin lineage went through an aquatic
phase, and it was during this time that the
key characteristics of humanity -
bipedalism, hairlessness, language, tool
making, etc. - all evolved. Rather than
our features being adaptations to drier
terrestrial environments, they are
adaptations to living in water. The key
figure in this model is Elaine Morgan, who
has written a number of highly persuasive
books making these claims, and who has a
strong following on the web and in the
more popular literature. She has, however,
failed to make many if any converts among
the mainstream of the discipline, so that to
the uninitiated it might appear that there
are two models of human evolution “out
there,” talking past each other.

Indeed, it is one of Elaine Morgan’s
complaints that her ideas have been
ignored rather than criticized or dismissed,
and that this is a case of “normal science,”
in the terms of philosopher of science
Thomas Kuhn, ignoring the radical
alternative paradigm rather than engaging
with it. In fact there have been a number
of serious examinations of the theory,
most of which have failed to find support
for it, but it is certainly the case that most
textbooks on human evolution - this one
included - simply ignore the aquatic ape
model.

This model is one among many
“alternative theories” of human origins,
and indeed in that light is one of the most
cogent and best argued. Others posit visitors
from outer space, or strange racial theories
of events deep under ice (for a survey of
these theories see Strange Creations by
Donna Kossy [Feral House, 2001]).

The existence of such models does raise
the question of what it is that distinguishes
a plausible model from an implausible one.
What is it that makes it reasonable to
discuss one model and to dismiss another
out of hand? Is the aquatic ape hypothesis a
reasonable explanation for many unique
features of humanity, and ignored because
it is a challenge to scientific orthodoxy, or is
it a crackpot theory? If it is the latter, then
should the scientific community spend time
and resources refuting it? If it is the former,
how can it become accepted as a good
model?

Hope this helps.