> laughin Wrote:
> > Kristin
> > do we not read what we post?
Yeah, I did.
> Am I the only person here who ever took anatomy
> and physiology, not to mention biology?
> > each body type has a maximum and minimum size
> > (which you are correctly arguing)
> > but it is not to be confused with the "most
> > convenient size"
> Most convenient? What the hell does that mean?
> I think the term you're looking for is stabilizing
> Oh, but that's right, you don't believe in
> evolution so there's no such thing.
I am using the term you posted
Haldane wrote an essay called On Being the Right Size in which he says:
The most obvious differences between different animals are differences of size, but for some reason the zoologists have paid singularly little attention to them. In a large textbook of zoology before me I find no indication that the eagle is larger than the sparrow, or the hippopotamus bigger than the hare, though some grudging admissions are made in the case of the mouse and the whale. But yet it is easy to show that a hare could not be as large as a hippopotamus, or a whale as small as a herring. For every type of animal there is a most convenient size, and a large change in size inevitably carries with it a change of form.
Let us take the most obvious of possible cases, and consider a giant man sixty feet high—about the height of Giant Pope and Giant Pagan in the illustrated Pilgrim’s Progress of my childhood. These monsters were not only ten times as high as Christian, but ten times as wide and ten times as thick, so that their total weight was a thousand times his, or about eighty to ninety tons. Unfortunately the cross sections of their bones were only a hundred times those of Christian, so that every square inch of giant bone had to support ten times the weight borne by a square inch of human bone. As the human thigh-bone breaks under about ten times the human weight, Pope and Pagan would have broken their thighs every time they took a step. This was doubtless why they were sitting down in the picture I remember. But it lessens one’s respect for Christian and Jack the Giant Killer.
Haldane used the term "most convenient size"
I take that to mean the optimum size for conditions
if you dislike it
take it up with him.
He says there is a limit to how big or how small a certain "form" can be
but that there is variation within it
here's a view of what happens when creatures are pressed
One of the most intriguing enigmas comes from Flores, an island in Indonesia. It concerns the Komodo dragon, which lives on Flores as well as on nearby Komodo. By all appearances, this voracious monitor lizard represents an archetypal case of gigantism. Thought to have grown huge on a diet of Stegodon, an extinct elephant-like creature that became a pygmy on Flores, the Komodo dragon today can grow up to 10 feet long and weigh 330 pounds; it can drag down and devour deer, water buffalo, and people. Yet while it is the world's largest lizard, a much heftier monitor lived in Australia during the Pleistocene—a 23-foot-long, 1,370-pound monster.
and wasn't there some other small creature found on Flores?
>But large mammals like that have a very
> > difficult time cooling themselves. When the
> > climate warmed up, they couldn't tolerate it.
> > same thing goes for elephants. They're
> > at retaining heat but not so good at getting
> > of it.
> > the most convenient size was changing
> > those already existing couldn't change their
> > but possibly their offspring could
> Their size wasn't changing. Their bodies simply
> could not cool themselves efficiently.
I didn't say their size was changing
I said that Haldane's "most convenient size"
for these organisms was changing
and those stuck with the wrong size
were pretty much screwed
but descendants could change size
> The same is true of humans. Smaller
> > get cold very easily--their body heat
> > quickly. Larger people can stay warm longer and
> > can tolerate much colder temperatures
> > so during the ice age, Larger people would be
> > favored
> > these days, not so much
> Nobody really lived in those conditions. Please
> understand that. People retreated to refugia--Cro
> Magnon, Neanderthal, Denisovan, the first
> Americans. You know about Meadowcroft. It's 16,000
> years old and may be 19,000. But the glaciers
> never got that far south. They stopped in your
> People were not equipped, either physically or
> technologically, to deal with the worst of
> conditions. For a long time it was thought that
> the Neanderthals were cold-adapted. Not true. They
> were adapted for warmth just as Cro Magnon was.
> > You are looking at it backwards
> > Now take an average 8 foot ice age human
> > who evolved to survive those conditions and and
> > scale him down
> > to 5' 7" of recent times
> That's BS. You're saying that humans, from the
> evolutionary inception, were 8 feet tall. There is
> absolutely nothing to support that.
> Please, Duane, let's deal in reality here
My point being that the "most convenient size" for
humans may be in a wider range.
You are treating today's humans as baseline normal
and deviation from this is a problem
I'm suggesting perhaps a larger size was possible
for a certain genetic strain of humans -giants
and that the warmer weather put them at a disadvantage
not physiological problems from growing so big