>> If you could include the references which
>> describe how -
>>
>> >the Sierra Nevada at 6,000 feet is ecologically and
>> >>climatically quite similar to parts of central and southern Canada,
Thanks, I wanted to ask the same. Let's see:
>(...)I can't think of one off the top of my head, I guess because
>the relationship between altitude and latitude has been understood since
>Merriam's 1898 description of San Francisco peak in Arizona and his
>introduction of the life zone concept, which has been revised by Dice in
>"Biotic Provinces of North America."
Come on, cite A.v.HUMBOLDT (Ideen zu einer Geographie der Pflanzen,
Tuebingen 1807) properly if you mean him (you obviously do so)!
> Anyway, many biotic
>elements have extended literally from the boreal regions of Canada south
>along the ecological corridor of the Cascades and the Sierra.
So you mean SW Canada (specifically, the Rockies of B.C.) and not "central
and southern Canada" (which has a continental climate) as you have written
before.
>Darlingtonia, for one.
Sorry, but this is perhaps the best example to disprove you because this
species does not even manage to reach Washington, much less so Canada (!).
> Pine martens, Stellar's jays, rubber boas, sequoia
>trees, wolverines, blue grouse, red fir, bigleaf maple, etc are all
>apparently of northern (=Canadian) origin and dispersed southward along
>the corridor into the Sierra and points south in some instances.
All these trees show distribution patterns rather different from any
Sarraceniacea, chorologically (I renounce to discuss non-plants in this
context). Let us compare comparable things.
>Their
>presence in the Sierra indicates that ecological and climatic conditions
>are not sufficiently hostile to exclude them,
This is true but...
>that is, in fundamental ways
>the Sierra Nevada biotic region resembles the Canadian more than it
>resembles the rest of California's biotic regions.
Not this way in our case. Montane floras are frequently different from the
planar ones at the same geographical latitude but still a good deal of
their species (and especially of the endemic ones!) have their phylogenetic
roots in the plains beneath their feet. _Darlingtonia_ did rather certainly
reach the Cascade Range from the (?S-)E and not from the N.
> Further, the
>mid- and high- Sierra coniferous forests are virtually identical in all
>ecological respects except species composition to those of boreal Canada.
But we are exactly talking about species composition. (BTW: how do you want
to discuss "ecological respects" excepting species composition?)
Please don't get me wrong. I do not want to annoy you but progress and
improvement are more frequently born from opposition than from applause.
Thus, it is one of my hobbies to disagree. Barry, Andreas, Fernando & al.
can certainly confirm this (or rather contradict?). ;-)
Kind regards
Jan