Re: all serious PAs now belive the savanna hypothesis.

Paul Crowley <dsfdsfdsfs@xxxxxxxxxxxx> wrote:

Other things being equal, coastal sites of
2.6 mya should be at about sea level now.
BUT other things are rarely equal. Firstly
the sea advanced and retreated hundreds or
thousands of times during hominid occupation
(before and around 2.6 mya, and in recent
times). When seas advance, wave action rips
up the ground. Go to any coast and note the
difference between the ground above the water
and that below (i.e. that which you can see
when the tide goes out).

Lots and lots of sediment.

But where does all that huge amount of
sediment come from? It's the land being
churned up as the sea advances. Those
huge sand-banks off the coast of many
continents (such as North America) are
mostly a temporary phenomenon, and will
soon get washed away into the ocean
(i.e. within a few tens of thousands of
years). In that sediment are minute
traces of ground-up hominid fossils, each
fossil scattered over probably hundreds
or thousands of miles.

Not every land/sea interface has the precipitous character of an Irish
limestone cliff. Where low land interfaces with the sea there can be
miles of mudflats (e.g. Waddensea), saltwater marshes, or mangroves.
Here the transition is much more gradual. The sediments in such areas
can come from hundreds of miles away through rivers and currents. And
in particular when tectonic processes lower the crust huge amounts of
sediment can accumulate before erosion reverses the proces.

Ideal for preservation. Marine sediments provide the
best fossil record.

It's ideal when the fossil arrives in
one piece an eon later, and is not then
exposed above water and then reclaimed
by the sea. Hominids fossils would
rarely have been deposited in one piece
in a marine sediment.

So we would not expect coastal sites to
survive. But occasionally they do. Of
course, those of >2.6 mya will be in Africa.
The best hominid sites found in Africa are
found close to paleo-coasts:

No, they're not. Get some better information on the
geology of the Afar triangle

The Afar triangle was the Afar sea.

Then where is the Afar marine fossil record?
Just because Elaine Morgan said so in one of her books doesn't make it
true. Even if the Danakil Depression was once a sea-arm it would still
be hundreds of miles away from Hadar. Saying that the Hadar hominids
were close to the paleo-coast is like saying that the chimpanzees of
the Tai Forest in Ivory Coast are close the coast (if so, they still
have a rainforest ecology)

It dried up leaving large salt deposits.

Never heard of salt lakes?

And what about Sterkfontein, Swartkrans,
Koobi Fora?

Mostly the remains of refugee groups,
which had fled inland -- the only
apparently safe direction. (Therefore
predominantly young and male.)

Paleobull***.

Bahr el Ghazal,

Is anything there reliable?

Yes, KT12/H1, aka "Abel"

Gerrit
.

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