Re: AAT:A method to falsify

13 Oct 1995 12:27:14 GMT

Organization: George Mason University, Fairfax, Virginia, USA

H. M. Hubey ( wrote:
: David Froehlich <> writes:

: >by suggesting that the water temperature anywhere exposed to the
: >atmosphere and not heated by volcanic activity could be 98.6 and that
: >hominids were living in it.

: 1) I don't know how hot the earth was during its prehistory and
: asked for it

Perhaps up to +5-10 degrees Celsius during the warmer periods (Cretaceous
and Eocene).

: 2) I don't remember saying that the oceans were all 98.6 but
: I don't know that it never was

Almost certainly never was. The warmest oceans were apparently in the
tropics in the Cretaceous, and I've seen an estimate of around 30-35
degrees Celsius. They had an unusual fauna (rudistid clams).

: 3) It would not have been impossible for some specific
: location (an isolated patch in an equatorial region) to
: have been this temperature.

It would have been highly unlikely.

: 3) Until there's some universally accepted reason as to why this
: number i.e. 98.6 is the standard body temperature of mammals
: it seems that people should ask for it

It isn't. There's a good deal of variation between species. In addition,
many species regulate their temperature so that it varies markedly. The
driving factors are enzyme efficiency, basal metabolism rate, and growth

: 4) Finally, the first mammal had to develop somewhere and it
: could have easily happened in some place where the water was
: exactly around this temperature

Wrong. Read up on mammalian evolution during the Mesozoic. This comment
is over the top.

: >The ratio of two isotopes of oxygen can be measured. The change in
: >del018 can be directly tied to global average temperature. These 018

: Oxygen would have to be locked up in something. Is it the ice
: caps in which they find the oxygen (along with the other gases)
: and from which they posit earth temperature?

Oxygen gets tied up in carbonate rocks. To maintain the current
atmosphere, carbon has to be sequestered in elemental form.

: There must be an independent way to confirm the age of the
: ice in that case otherwise it's circular. It certainly can't go
: beyond the time period in which the earth would have been much warmer
: and ice caps melted.

: >curves indicate pretty precisely that the earth has not been that warm
: >since at least the Cretaceous (I am not a geochemist so thie above is a

: 135 million year old ice caps?? I guess the oxygen is supposed to
: be trapped in something else, like rocks??

: >bit of a simplification. If there is a geochemist in the audience would
: >you please post a follow up if I am leaving something out).

: Yes, I second this request. I'd like to know how we know the
: temperature of the earth.

You're speculating far beyond your scientific background. That's an
excellent way to make a fool of yourself. Some of these comments are way
over the top.

Harry Erwin
Home Page: (try a couple of times)
PhD student in comp neurosci: "Glitches happen" & "Meaning is emotional"