Re: More Morgan/Nicholls

Kevyn Loren Winkless (
7 Jan 1995 20:20:01 GMT

In <> (Elaine Morgan) writes:
>interesting? (But "savannah" was not how Johanson
>described Lucy's habitat. "Lush", he said.)
Rainforests are lush too. Lush environment means that there is a great
deal of free and captured moisture in the system...not necessarily in
the form of open water.

>RE: Diving adaptation. I forget who said that this was
> Let's get it clear. Any mammal dropped into water stops
>breathing as a unconditioned reflex, and cessation of
>breathing causes some slowing down of the heartbeat.
>These reactions are more highly developed in but not
>exclusive to aquatic mammals.
> But: The striking capacity humans share with all diving
>mammals and all diving birds is conscious control of
>breathing. A dolphin can be trined to respond to a
>command to retrieve different specified objects from
>different depths in a training tank or pool. The amount of
>air it inhales varies according to the amount of time
>it knows it will need to be underwater.
> Humans have the same kind of volitional breath control.
>Apes do not. That is the sole reason why it is virtually
>impossible to teach them vocal language however adept
>they become at sign language.

>Elaine Morgan

Humans have conscious control of breathing. This is true, and as you
have pointed out it is a difference of degree not a unique trait.
Dolphins and other marine mammals had the need for diving as a driving
force to develop such efficient control of breathing, and as a result
they are able to produce sounds with sufficient precision that we think
they may use them to communicate. Perhaps the drive was in the opposite
direction for Homo ancestors: the need for precise communication over
distances drove the evolution of breath control. In the sense of vast
distances, the savanna is similar to a stretch of ocean (I know, that's a
bit of a stretch..).
I will try to dig up the exact references for you, but James McKenna
(1986 An Anthropological Perspective on the Sudden Infant Death Syndrome
(SIDS): The role of Parental Breathing Cues and Speech Breathing
Adaptation. Special Issue of Medical Anthropology 10(1)) points out that
conscious control of breathing begins to manifest in human infants
between 2 months and a year or so (interestingly, this is a similar
window to the incidence of SIDS...he makes that connection, but I won't
go into it, for which I'm sure you are grateful), using as evidence
extensive experimental data collected in psychology and medicine. It
seems to me that while conscious control of breathing is advantageous to
a marine mammal, it is just a little dangerous for such breathing
patterns to develop so late in life. One would expect development within
a few hours or at most days. (though I have yet to find a source which
specifically states the period of time it takes dolphins to learn). I
think it is probably safer to conclude that breath control is associated
with speech and not diving.


"...I drank WHAT!!?" - Socrates