Accelerated evolution

This was always going to be a hectic week, but a major cock-up by a Dutch airline(I won’t mention any names) (Keeping Luggage in aMsterdam) (cough) means that I have a less stressful morning today, but has instead moved that stress to the next couple of days.

It does give me chance to share this article which I saw through Brian Micklethwait’s blog, though.

Author Matt Ridley details several (or more) examples of apparent accelerated evolution in fauna living in urban environments. Ridley uses this as the basis of a potential argument for the removal of restrictions on building in the green belts surrounding our cities.

Suburbs are already richer in wildlife than most arable fields in the so-called green belt, making environmental objections to housing development perverse.

I’m not about to join his side in that discussion, especially given the lack of any citations in his article (although to be fair, it was a column for The Times originally, not a scientific paper). Simply because there are new subspecies emerging in our towns and cities surely doesn’t mean that we should willfully eradicate their country cousins.

Or unwillfully for that matter, I suppose.

The city is a harsh environment, with many evolutionary pressures, and they are what are driving this accelerated natural selection.

Blackbirds first showed up in London in the 1920s, later than in continental cities. Studies in France and the Netherlands found that urban blackbirds were rapidly diverging from rural ones. They tend to have shorter beaks and wings, longer intestines and legs, as well as higher-pitched songs. They may soon count as a separate species, just as town pigeons are very different from their rock-dove cousins.

Some of them are related to streetlights and traffic noise, but a worryingly large number appear to be associated with the toxins found in our habitats. And while it’s remarkable, impressive, incredible that bird and fish are adapting so quickly and readily to these potential problems, we should note that the wider picture is wholly unpretty.

We’re not evolving anywhere nearly as quickly as our urban wildlife.

Still, these provisos and warnings aside, it’s both fascinating and amazing to me how we’re shaping the lives of the wildlife around us, and the plan is definitely to do a bit of further reading on this.

For the science.

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