In “Brainy molluscs evolved nervous systems four times” (New Scientist, September 16, 2011), Ferris Jabr tells us,
The mollusc family includes the most intelligent invertebrates on the planet: octopuses, squid and cuttlefish. Now, the latest and most sophisticated genetic analysis of their evolutionary history overturns our previous understanding of how they got so brainy.
The new findings expand a growing body of evidence that in very different groups of animals – molluscs and mammals, for instance – central nervous systems evolved not once, but several times, in parallel.
This is more consistent with either design or law than with Darwinian selection without plan or purpose.
Now, all this is based on certain methods of configuring how evolution happened. The methods could be right or wrong. But if they hold up,
The four groups that independently evolved centralised nervous systems include the octopus, a freshwater snail genus called Helisoma, Tritonia – a genus of strikingly coloured sea slugs – and Dolabrifera, another genus of sea slugs, albeit less aesthetically interesting.
Which all just happened, right?
Smart octopus tales:
See also: Here’s the best online port of call for convergent evolution.