Whereas the Magpies in Tassie are smaller. If Bergmann's rule holds
true the Tassie Magpies must be a separate species.
John Leonard
2008/9/12 Graham Turner <>:
> I remember head south to Lancefield in Victoria 6 or so years ago and being
> amazed at the size of magpies when compared to the ones I see around the
> Blue Mountains. Seems to work for me. Maybe its not applicable to
> everything, but it is a 'rule' no a 'law.
>
> Cheers
> Graham Turner
>
>
> Bergmann's Rule
>>
>> From Wikipedia, the free encyclopedia
>
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> In zoology, Bergmann's rule is an ecogeographic rule that correlates
> latitude with body mass in animals.[1] 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. The rule
> is named after a nineteenth-century German biologist, Christian Bergmann,
> who first formulated the rule in 1847. The rule is often applied only to
> mammals and birds (endotherms), but some researchers have also found
> evidence for the rule in studies of ectothermic species.[2] Bergmann's rule
> is controversial amongst researchers and its validity has often been called
> into question,[3] and there is division amongst scientists about whether the
> rule should be interpreted to within species variation or among species
> variation.[1] Although several mechanisms have been suggested to explain the
> rule there is no clear explanation for why the pattern exists.
>
>
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