[Right Wing Professor]

If you have two competing environmental factors, and a linear relationship between the relative survival and the strength of the factor (and all relationships are linear looked at on a small enough grid :-)), then the interference will be second order. Unless you have some specific reason to expect there to be competition or cooperativity between the two factors (e.g, if they both act via the same gene), you would expect the coupling to be effectively zero.

There's no reason why ten or a hundred selective pressures shouldn't operate entirely indepedently on the same population.

But, I agree, the experiment could be done. I would bet dollars to donuts unless you choose two pressures that are specifically designed to interfere, they will act independently.

[grey_whiskers]

But, I agree, the experiment could be done. I would bet dollars to donuts unless you choose two pressures that are specifically designed to interfere, they will act independently.

'Tis where the rubber meets the road--did the scientists know, or have a pretty good estimate, in advance --
where the point mutations would have to be in order to increase survival within an increasing temperature environment?

If not, then I think it would be hard to know in advance which pressures would interfere, or not.

E.g. on a much earlier crevo thread I thought I read of the fact there were six mutations which all had to occur in rapid succession in order to generate a flagellum. Even with complete knowledge of the an organism's chromosome, it still looks like a tall order computationally in order to predict *in advance* the possibility of that occurrence.

Which would make the rigorous design of an experiment to predict and effect specific mutations harder to do.

(But that *would* be where the fun would be...as well as driving PETA completely Bat-sh*t.)

Cheers!