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Re: Now it's the sheep ...

So sheep can change colour too?
Appropos the earlier comments on evolution and the usual debate about how long it would be necessary for evolution to produce such complex organs as the eye, for example, I am tempted to suggest that evolution appears to demonstrate some remarkably rapid changes, if the pressures are significantly extreme.
In the days when there really was pollution in our industrial towns (most people today seem to think we are polluting more than ever before even though the evidence on the UK environment agencies website shows particulates to be at a fraction of their level in the 1950s-60s) London Butterflies were dark in colour but with the introduction of smokeless fuels and the subsequent rush for gas, the drop in particulates resulted in the background colour of tree bark to lighten considerably. It wasn't very long before butterflies were found to have matched the colour through the simple effect of bird predation on them - dark butterflies being far more obvious than light.
I seem to recall reports of Vietnamese insects exposed to massive doses of agent orange quickly adapting to utilise this and other chemicals in their own defense mechanisms. (I'm running on memory here, so I'll need to check back on this).
SO it seems to me that evolutionary changes need not necessarily be long term incremental steps but a series of very rapid changes in the right circumstances. The examples I give are, of course, very simple, but I think the principle is possibly a valid one to extend to more complex changes. More importantly, given how little we really know about preceding generations (most corpses leaving little trace).
I am suspicious of estimates of time required for such changes at any rate and especially those that are used to exclude any particular line of investigation or which appear designed to support a particular interpretation of history (the apparent influence of pre-conceived ideas on experimental outcomes is somewhat alarming).

So I wouldn't be the least surprised that climate change could have short term influences on species. That isn't, of course, to say that that is the only cause of changes and while it is interesting to note the comment about island populations, that is an observation without a cause.

Admitting that climate change can possibly have a marked influence does not necessarily lead us to conclude climate change is due to man or that it is bad.

Perhaps all Alarmist declarations (and AL Gore's film) should have a small print warning that says "Temperatures may fall as well as rise. Changes are not necessarily either harmful or beneficial".)

Re: Now it's the sheep ...

This claim that sheep are getting lighter in colour due to global warming contradicts a rule in zoology called "Gloger's Rule".

In Gloger's Rule, plumage and hair tend to get darker in the warmer, more humid climates seen as you get closer to the equator. The darker hair or plumage apparently helps in resisting bacterial attack.