Two cents of (natural) intelligence

Several months ago, my previous attempt to speak here about artificial intelligence, wondering if computers could participate in the invention of language, met a total lack of feedback (it's not too late for second thoughts, dear reader). I found it quite frustrating, hence another attempt to venture on this slippery debate ground.
+Emeka Okoye in the follow-up of the previous post on facets makes strong points. When I wonder how much intelligence we want to delegate to machines, and for which tasks, the answer comes as a clear declaration of intention.
We are not delegating "intelligence" to machines rather we are delegating "tasks" ... We can have a master-slave relationship with machines ... We, humans, must be in control.
I appreciate the cautious quote marks in the above. But can it be that simple? Or just wishful thinking, as +Gideon Rosenblatt is warning us in a post entitled Artificial Intelligence as a Force of Nature. The connected machines ecosystem, distributed agents, neuronal networks and the like, are likely to evolve into systems (call them intelligent or not is a moot point) which might soon escape, or has already escaped if we believe some other experts on this topic, the initial purpose and tasks assigned by their human creators, to explore totally new and unexpected paths. This hypothesis, not completely new, is backened here by a comparison with evolution of life, of which the emergent ambient intelligence would be a natural (in all meanings of the term) follow-up.

But evolution of technologies, from primitive pots, knifes and looms up to our sophisticated information systems, is difficult to compare to the evolution of life and intelligence. The latter is very slow, driven by species selection on time scales of millions of years, spanning thousands of generations. Behind each success we witness, each species we wonder how it perfectly fits its environment, are forgotten zillions of miserable failures which have been eliminated by the pitiless struggle for life. Nothing can support the hypothesis of an original design and intention behind such stories.
It's often said, like in this recent Tech Insider article, that comparing natural and artificial intelligence is like comparing birds to planes. I agree, but this article misses an important argument. Birds can fly, but at no moment did Mother Nature sat down at her engineering desk and decided to design animals able to fly. They just happened to evolve so over millions of years from awkward feathered dinosaurs, jumping and flying better and better and we now have eagles, sterns and falcons. On the contrary, planes were from the beginning designed with the purpose of flying, and in barely half a century they were able to fly higher and quicker than the above natural champions of flight.

To make it short, technology evolves based on purpose and design, life (nature) has neither predefined purpose nor design. Intelligence makes no exception to that. Natural intelligence (ants, dolphins, you and me) is a by-product of evolution, like wings and flight. We were not designed to be intelligent, we just happened to be so as birds happened to fly. But computers were built with a purpose, even if they now behave beyond their original design and purpose, like many other technologies, because the world is complex, open and interconnected.

Let's make a different hypothesis here. Distributed intelligent agents could escape the original purpose and design of their human creators, maybe. But in such a case, they are not likely to emerge as the single super intelligence some hope and others fear. Rather, like the prebiotic soup more than three billions years ago, its spontaneous evolution would probably follow the convoluted and haphazard paths of natural evolution, struggle for survival and the rest. A recipe for success over billions of years, maybe, but not for tomorrow morning.