Human-like intelligence on this planet... (Score 2, Interesting)

would be a nice thing (to paraphrase Gandhi).

Intelligent life has clearly evolved many times on earth, from dinosaurs to dolphins, octopi to owls.

Is there any strong evidence that no technological intelligence ever evolved on earth before America was born (irony)? I mean before humans came along?

If we all died tomorrow in an asteroid blast, what evidence would there be of our existence in a mere million years?

There was good article on this in New Scientist once which concluded the answer was 'little'.

Just a weird thought.