One possible explanation for the WOW! signal here, I think.
Maybe, in order to survive long enough to be able to colonize other planetary systems, it’s necessary for a species to leave behind expansionist ideas and overpopulation, and such a species wouldn’t consider colonization of other places an end in itself, rather than a means to one. It may be that they could colonize but, without the need to do so, there’s no desire.
It’s difficult to imagine a species with millions of years of history, though, our own being so comparatively short.
Perhaps, when the universe starts to contract, and the distances are a bit smaller, there could be a kind of Family reunion, before everything gets put into that one small point…again:D
ps dont want to hijack but that whole Big Bang thing, makes me 
confused!!
It’s generally thought that the universe will continue to expand forever. Eventually everything will be so far apart that, even if someone were still alive, they would look into the night sky and see no stars. That also means that all the energy will eventually be so dispersed that everything will become a uniform temperature and nothing of much interest can happen - certainly not life.
Yeah, but we’ve got trillions of years before that happens, and during that time all the countless invisble red dwarfs in the sky will be getting brighter and brighter until the Galaxy is full of Sun-bright stars. The Galaxy will be a very habitable place a trillion years from now, more than it is today.
After that- well some people have been making plans to live in the deep future - check out Freeman Dyson’s essay
Time Without End - Physics and Biology in an Open Universe
http://www.aleph.se/Trans/Global/Omega/dyson.txt
My post was just a response to Section Maker:Jupe’s “Big Crunch” speculation. I’ll certainly read that when I get a chance, though.
ugg the Big Freeze instead! Some serious down time coming with that, or no time! Jeez, depressing, time to swim in the ocean 
I went over to wikipedia and put the evolution of life on a timeline to get a sense of where the bottlenecks were.
Billion years ago
4.5 Earth formed
4.4
4.3
4.2
4.1
4
3.9
3.8
3.7 Earliest Evidence for microbial life
3.6
3.5 Oxygenic Photosynthesis --------
3.4 |
3.3 |
3.2 |
3.1 |
3 |
2.9 |
2.8 |
2.7 |
2.6 |
2.5 |
2.4 Oxygenation of atmosphere --------
2.3
2.2
2.1
2
1.9
1.8 Eukaryotes: Still single celled, but with orgenelles
1.7 Multi-cellular organisms
1.6
1.5
1.4
1.3
1.2
1.1
1
0.9
0.8
0.7
0.6 Bilateral organisms
0.5 Land plants, Cambrian explosion
0.4
0.3
0.2 Dinosaurs
0.1
0 Humans
A: Hard to say in many ways. It’s possible that life arose quickly, but evidence for it would be dodgy in early Earth days. But at any rate it took 1.2 billion for evidence of life to appear and another 1.9 billion for Eukaryote evidence to arise. Eukaryotes may have arisen earlier though. Still there’s some evidence that the bottleneck is creating microcellular organisms with their own organelles. Interestingly, multicellular life occurs a mere 150 million years later. I takes another 1.1 billion years for billateral organisms to arise. Then the Cambrian explosion occurs and the pace really picks up.
So: bottleneck candidates:
Creation of microscopic life: Not clear.
Creation of Eukaryotes from earlier forms of microscopic life: I’m guessing this is a big bottleneck, but that’s a WAG.
Creation of multicellular life from Eukaryotes: pshaw. That’s relatively easy. Unless Eukaryotes actually appeared much earlier.
Creation of complicated animals with bilateral symmetry from multicellular life: Actually this took a while. 1.1 billion years.
Everything else: pshaw.
Lots of animals use tools. Lots of social mammals have an arms race prompting increasing cognitive abilities. (canines, dolphins, primates). Put the two together and you get intelligence. Asteroid impacts can set the process back of course.