Peter Hickman wrote:

Paul Bramscher wrote:

Why?  Intelligent, mammalian and non-mammalian cooperative life on Earth  all developed along social considerations.  Herds, tribes, cities, hives, etc.  Clusters or communities may be better hallmarks (though not exclusive) of intelligence and cooperation than most.

This is probably necessary but certainly not sufficient. Algae forms clusters as do slime molds even to the extent of symbiotic clusters with other molds. But I would not attribute and intelligence to slime mold or algae.

That's right -- and why I added the "though not exclusive" caveat in my post above.  A sort of "all dogs are mammals, but not all mammals are dogs" problem.

So what makes intelligent symbiotic clusters different from non-intelligent ones?  I'll aruge that Anthony's post in this thread has some merit.  Straight lines, large-scale geometry (which nature seems to abhor), and redistribution of certain chemistry (especially metals) might have something to do with it.

Birds congregate by the tens of thousands during nesting, but they don't great large-scale geometry.  They can and do modify the chemistry of the environment (through their droppings, etc.) but the signature of a city is significantly different than the signature of algae mats, bird droppings, a buffalo herd's grazing range, etc.