To quote the definition as it is stated in the Wikipedia, 'In zoology, Bergmann's rule is an ecogeographic rule that correlates latitude with body mass in animals. Broadly it asserts that within a species the body mass increases with latitude and colder climate, or that within closely related species that differ only in relation to size that one would expect the larger species to be found at the higher latitude.'( http://en.wikipedia.org/wiki/Bergmann )
George W. Gill gave an important paper in regards to Bergmann's rule as applied to reported descriptions and footprints of Sasquatch in the far west of North America in 1980. [1] Gill's estimates were staged for different states at different latitudes and included separate tabulations for reported heights in Sasquatch reports and also heights figured from the tracks.
Gill's estimates were that the reported track lengths in California ranged from 12 1/2 to 18 inches long, with a mean of 15 inches and corresponding to the separate stature estimations of 6 to 9 feet tall with an average of 7'4." In Oregon the range of footprint lengths was from 13 1/2 to 20 inches with a mean of 16 9/10 corresponding to stature estimations of 6 1/2 to 9 1/2 feet with a mean of 8 feet tall. In Washington the footprints had a length of 13 1/2 to 22 inches with a mean of 17 1/10 inches and stature estimates of 7 to 10 feet tall with a mean of 8'4". In British Columbia and Western Canada the tracks were from 15 to 24 inches long with a mean of 18 1/2 inches long and stature estimates of 7 to 14 feet tall, the highest estimate being in doubt and the mean being 8'8."
The smallest of the Western Canadian Sasquatches are at the size of the average Californian ones, and the largest Californian Sasquatches are at the size of the average Western Canadian ones.
I have made a chart illustrating Gill's figures and I append it here. I had also done a rough statistical survey and arrived at results equivalent to Gill's, and with the results that I concluded were an illustration of Bergmann's Rule. Furthermore, Grover Krantz [2] spoke of the typical Sasquatch in the Washington area as typically having a male 7 feet 8 inches tall and weighing up to 800 pounds, with a female typically 6 feet 6 inches tall and weighing 500 pounds. He put a maximum size at 10 feet tall and 1000 pounds. After consulting Bob Titmus the latter said, on the basis of his experiences in Southern Alaska, he would modify those figures upward by as much as 15% for height and as much as an additional 50% in weight. Krantz added "And he may be right".
I have made a chart illustrating Gill's figures and I append it here. I had also done a rough statistical survey and arrived at results equivalent to Gill's, and with the results that I concluded were an illustration of Bergmann's Rule. Furthermore, Grover Krantz [2] spoke of the typical Sasquatch in the Washington area as typically having a male 7 feet 8 inches tall and weighing up to 800 pounds, with a female typically 6 feet 6 inches tall and weighing 500 pounds. He put a maximum size at 10 feet tall and 1000 pounds. After consulting Bob Titmus the latter said, on the basis of his experiences in Southern Alaska, he would modify those figures upward by as much as 15% for height and as much as an additional 50% in weight. Krantz added "And he may be right".
The two sets of figures also fit exactly in the same size ranges as predicted by Gill's estimates, with Titmus' Southern Alaskan estimates fitting right in at the top. The additional estimates give male heights of 9 feet and a maximum weight of 1200 pounds, and a female height of 7 feet 6 inches with a maximum of 750 pounds. Krantz's top limit of 10 feet tall plus an additional 15% comes to 11' 6 inches. The largest estimates given for Gigantopithecus are in the range of 12 feet tall and a weight of 1313 pounds for a really big male, listed independantly in the literature, which is a close match and what I would propose as the absolute maximum possible size.
Another rule frequently stated in conjunction with Bergmann's rule is Gloger's rule, which states that animals of the same species that inhabit warmer and more humid climates tend to be darker in colour (http://en.wikipedia.org/wiki/Gloger) and Gill also noted in his paper that the number of lighter-coloured Sasquatches in the reports is 13% in California and Oregon but 26% of the reports in Washington and Western Canada. That is twice as much, a noticeable increase in blonde Sasquatches as the latitudes increased.
Another rule frequently stated in conjunction with Bergmann's rule is Gloger's rule, which states that animals of the same species that inhabit warmer and more humid climates tend to be darker in colour (http://en.wikipedia.org/wiki/Gloger) and Gill also noted in his paper that the number of lighter-coloured Sasquatches in the reports is 13% in California and Oregon but 26% of the reports in Washington and Western Canada. That is twice as much, a noticeable increase in blonde Sasquatches as the latitudes increased.
The adherance of the reported Sasquatches to known biological rules argues for the existence of real creatures being reported rather than creatures merely made up or hallucinated. And the size estimates seem to be paralleled in Eastern Asia as well, especially in China and Manchuria; and the close correspondance of the size estimates to published estimates for Gigantopithecus is probably also no accident.
[1] "Population Clines in North American Sasquatch as Evidenced by Track Lengths and Estimated Statures" in Manlike Monsters on Trial: Early Records and Modern Evidence, Edited by Marjorie M. Halpin and Michael M. Ames, U of BC Press, 1980.
[2] Grover Krantz, Big Footprints (1992 edition) p.146
[1] "Population Clines in North American Sasquatch as Evidenced by Track Lengths and Estimated Statures" in Manlike Monsters on Trial: Early Records and Modern Evidence, Edited by Marjorie M. Halpin and Michael M. Ames, U of BC Press, 1980.
[2] Grover Krantz, Big Footprints (1992 edition) p.146