https://en.wikipedia.org/wiki/Population_bottleneck#Humans
The real problem is that an individual can only learn so much and 1,000 can't support the skills needed to run something like a modern civilization.
The scientific breakthroughs needed to make an interstellar spaceship are so far away that we must assume they'll be post-singularity tech.
https://en.wikipedia.org/wiki/Population_bottleneck#Humans
The real problem is that an individual can only learn so much and 1,000 can't support the skills needed to run something like a modern civilization.