What Creates Leptosomic Individuals?

[Schutzstaffelor]

it's generally known to anthropology experts that tropical and sub tropical regions tend to produce very leptosomic individuals, due to the fact that the ratio of surface area to volume is high and heat is dissipated rather quickly. (the masai people in africa are one of the lankiest people on earth) whereas people living arctic and sub arctic regions tend to have more heavy, muscular, and stocky builds.

since this is the case, why is it that the Scandinavians, who are native to the se arctic regions, are known to be generally leptosomic individuals?

[Agrippa]

it's generally known to anthropology experts that tropical and sub tropical regions tend to produce very leptosomic individuals, due to the fact that the ratio of surface area to volume is high and heat is dissipated rather quickly. (the masai people in africa are one of the lankiest people on earth) whereas people living arctic and sub arctic regions tend to have more heavy, muscular, and stocky builds.

since this is the case, why is it that the Scandinavians, who are native to the se arctic regions, are known to be generally leptosomic individuals?

I described what my interpretation is here on Skadi:
http://forums.skadi.net/showthread.php?t=38063

To put it short:
a) The basic type for the temperate cold and cold environment in Northern Europe was the Cromagnid (Dalofaelid, Palaeatlantid) race, they were mostly Hunter-Gatherers and dominated until the Last Glacial Maximum ended in Europe, leptomorphic types occured, but were rather seldom.

b) Europe was getting warmer, more population, in the more Southern regions of Europe first, Scandinavia was getting warmer too (at certain times significantly warmer than it is now) - both happened, people came from the South and in the North leptomorphic types had as much or in some aspects (endurance, energy etc.) even more advantages.

c) The subsistence pattern changed, more mobile, warlike and group oriented types were selection, again leptomorphics had minimum as much or most likely because of certain psychic tendencies even more advantages.

d) Even when the climate was getting colder again, the technical developments and subsistence was evolved enough for not selecting more cold adapted types with more robust body type, pyknomorphic surface and more fat and muscles too strong.

e) Cromagnids survived because climate changed again and more sedentary lifestyle began in those areas in which they managed to survive during "the flood" and they adapted themselves to the new technologies and subsistence pattern. In pure areas their rests were partly or fully infantilised - Alpinisation and Baltisation, because farmers lived areas which suffered from hunger, exclusively and poor herbal food, plagues, monotonous work and strong r-selection in the surviving, still expanding populations - especially poor areas away from coasts, in the inner lands of Europe were affected.

So Europe was getting warm enough for leptomorphic types which had definitely physical, quite probable psychic advantages. This lead to their success after the LGM, especially in the mobile and warlike societies. For the temperate warm and temperate cold areas, leptomorphic build is sufficient for surviving short periods of cold with enough energy and (relatively) advanced technology. Only on the long run, with bad technology and social structures, in constantly colder environment, the tendency towards first a Cromagnid-Athletic, if going on and getting even more extreme, very extreme, Tungid/Mongolid-Athletic body forms would be STRONGLY selected.

[Dr. Solar Wolff]

Since Neanderthals left us, sapiens has used primarily culture not biology to adapt to new conditions. The royal families of Hawaii are probably the biggest, bulkiest, heaviest people in the world and they live in a subtropical or tropical region. Some eskimos are very lean and muscular. Some of the leanist people are the Cantonese, derived from northern Mongoloids. There are many exceptions to the rules of Allen (or is it Bergman??).

[Agrippa]

Its interesting you mention the Cantonese, because the Sinids had in East Asia a similar role as the Nordoids and similar variants in Europe. They spread as mobile farmer warriors and were most likely the result of Northern Mongolids mixing with (not that primitive and in the widest sense) Australoids, but absorbing them mostly. Due selective processes only those elements were kept, which were advantageous for this expanding farmer warriors which marched South - which means the primitive features were selected away but the leptomorphic body type was kept.
You can see from North towards South that the legs get relatively longer - because of more and more Weddoid/Australoid influence.

Some Eskimos might be lean, but most aren't really and they had technological adaptations too and very specific physical adaptations, f.e. shorter legs as well. They are interestingly not as extreme as Tungids are, probably because they evolved in a niche with limited further developments.

As for some Polynesids, they lived as mostly plant-eaters as well, group selection, the best force of progressive developments in humans was almost eliminated in some areas.
In individual selection, certain ritual fights, if its about prestige and sexual selection, huge and very pyknomorphic types might have had a certain advantage.
There is the theory that during their voyages, only some those with enough fat reserves and a slower metabolism survived, this trend went on because of the partly poor food and in some areas famine for certain periods of time. Because of that certain relations between islands evolved, in some even birth control and tabus, and the ideal for pyknomorphic, even fat individuals was furthered more and more.
We might see similar things in certain African farmer groups or poor European farmer areas which lost a dynamic and healthy ideal, especially in periods of constant poverty, plagues and famine in which the non-existent becomes the rare ideal (compare with China - Buddha depictions, and Japan - Sumo). But in China and Japan efficiency was still more important than such ideals, at least in many areas and the general culture, mostly simple people favoured it, in certain Polynesian areas it was different because of the isolated position and the lack of efficient group selection.