I was just thinking about this topic the other day -- how hard was it to develop the genes that separate human intelligence from other primates? In other words, if all humans disappeared from earth, then given another couple dozen million years or so, what is the likelihood of another intelligent species coming about?
Of course, human intelligence is hard to pin down -- for my personal definition, it is the ability to specifically communicate new ideas to other members (i.e., not other members just picking up a skill from observation only, but for one to be a teacher), and to be able to (as a group) remember and pass down history. Oh, and the ability to develop a space program.
And also, this was an interesting exploration of the topic, with in utero electroporation of cortical matter to induce more brain growth: http://core.ac.uk/download/pdf/11034136.pdf
> Of course, human intelligence is hard to pin down -- for my personal definition
I suggest giving up on that question. Even if humans are not intelligent, there's at least one or a few properties of human brain matter that are causing all of these unexpected and unexplained results we observe from its operation.
My bet is that, if we did disappear and another species "caught up" so to speak, the descendants of modern chimps would take the crown, with the right evolutionary pressures, in 5 million years at the earliest. That's about how long ago we forked:
If we started a human-directed breeding program to develop chimps capable of language (arbitrarily chosen marker of intelligence) right now, I would guess we might be able to cut that time down to merely hundreds of thousands of years.
> If we started a human-directed breeding program to develop chimps capable of language (arbitrarily chosen marker of intelligence) right now, I would guess we might be able to cut that time down to merely hundreds of thousands of years.
Another option is to pick a collection of human genes that seem like they may be relevant, and just insert them into chimp genomes. Followed by something like your selective breeding program. I would be fairly surprised if it still takes 100k years.
Extremely high. There are a number of intelligent special on this planet right now: dolphins, elephants, whales, primates...
How likely is that there will be a sophisticated tool using civilization is a more interesting question. There are non human species that use tools[0], but they lack in sophistication. In order to start advanced technological civilization I think there are few conditions: ability to store information, ability to communicate information, and ability to utilize and improve tools.
There's also the primates that learned to modify sticks (i.e., peal off the bark) to stick in termite mounds, causing the termites to stick to the sap on the wood. This is an invented and learned behavior, but I don't know if there is any cases of a primate teaching another one this trick (vs. a primate picking it up by observation only).
Of course, human intelligence is hard to pin down -- for my personal definition, it is the ability to specifically communicate new ideas to other members (i.e., not other members just picking up a skill from observation only, but for one to be a teacher), and to be able to (as a group) remember and pass down history. Oh, and the ability to develop a space program.