In an interesting documentary on the habits of animals and insects, there was the explanation of why the Monarch butterfly flies a thousand miles to breed.

Basically it evolved to need the nutrients of certain plants, and breed on certain trees. Which were for hundreds of thousands of years located in the same warm place, tolerating at the edge of their extremes. As the ice age receded the butterflies kept to that locked-in regime but the plants slowly edged north because they couldn't cope with the increasing heat. The trees thrived where they were (heat or soil or something). So the butterflies migrated annually over ever longer distances, and evolved to forage more intensely to store energy.

The prognosis is that, this will happen to certain butterflies we have hitherto enjoyed in most of Britain. And is discernible already!

And isn't growing rocket lettuce easier in the last 50 years in the UK? It ain't rocket science............... or is it? Quantum lettuce anyone?


No hockey sticks were hurt in this analysis.