Re: Waking up covered in dew

Nick Maclaren (nmm1@cus.cam.ac.uk)
19 Aug 1996 05:28:05 GMT

In article <DwAGnz.A1v@inter.NL.net>,
Gerrit Hanenburg <ghanenbu@inter.nl.net> wrote:
>nmm1@cus.cam.ac.uk (Nick Maclaren) wrote:
>
>>>Pardon my intrusion, but why are you concerned about dew and even
>>>hypothermia? I thought all of this was supposed to be happening in a
>>>tropical semi-arid African savanna.
>
>>Grin :-) I grew up there! Most of it is at high altitude (5,000 feet
>>plus), and mild frosts at night are common in the dry season. While
>>dew is not the problem that it is in the UK, there is often enough to
>>make things wet, and it is often cold enough to cause hypothermia.
>
>But exactly where did you grow up? That can make a lot of difference.

Zambia which is, admittedly, colder than Kenya or Tanzania. But not
as much as all that.

> We're talking about possible ape/hominid country here.
> Goodall in "The Chimpanzees of Gombe" reports for the Gombe region an
> average maximum temperature ranging from about 25C-26.5C in the wet
> season and 27C-30C in the dry season,while the mean minimum
> temperature stays between 18.5C and 21C.

That is not exactly in the savanna! Yes, the Congo and West African
jungles remain pretty warm.

> As far as savanna is concerned,Sinclair in "Serengeti II" reports a
> relatively constant mean monthly maximum of 27-28C at Seronera
> (central Serengeti),while minimum temperature varies from 16C in the
> hot months (October-March) to 13C during May-August.
> None of these report nightly frost.

Part of the key is 'mean minimum', and another is altitude. Also,
note that I did NOT say 'nightly frost'. I have slept out near
there, and it was a damn sight colder than 13 degrees Celcius. I
take your point that humans could well have lived only in the areas
of the savanna that virtually never have frosts, but at least SOME
nights will have been cold whereever they were (on the savanna).

My main point is that all areas of the savanna have some coldish
nights, and many get quite cold (at least occasionally). This is
entirely different from the rain forests, which don't. I can
definitely witness that dew on naked skin could be a problem on the
high ground in the Kenya/Tanzania area, but not that early humans
lived in that particular terrain!

Nick Maclaren,
University of Cambridge Computer Laboratory,
New Museums Site, Pembroke Street, Cambridge CB2 3QG, England.
Email: nmm1@cam.ac.uk
Tel.: +44 1223 334761 Fax: +44 1223 334679