Here’s the joke:
One man and ten women are ship wrecked on an island. The only infertile woman looks at him and thinks, “Let’s colonize.”
What’s the punchline? Well, it’s that this may actually be possible.
Recently many people (including an organization called Project Hyperion comprised of scientist dedicated to space travel) have been looking at the mechanics interstellar travel. One facet of this science-fiction is the on-going argument of colonization or more specifically colony starting numbers. A large number that has been thrown around in recent years is 40,000; this number allows multiple potential mating partners and room for mistakes such as disease and disaster. Though this number is viable for the most successful colonization, it is far from the minimum success number. Even the article cited above suggests that the same could be done with 10,000 (though there is smaller margin of error). Another article suggests that a number as low as 80 could effectively colonize if social-engineering were implemented and no accidents happened.
Since these results were released many in the general population have played with the figures and gotten them even lower as seen in this blog post on a world building discussion page.
“Suppose we need to reach a population with 80 unique genetic sets to go past the tipping point. Lets do a quick calculation on how this can be achieved if fertile women are able to give birth to 4 children on average and have taken a bunch of frozen sperm samples with them:
- Generation 0: 10 (fertile) women and 10 frozen samples
- Generation 1: 20 women and 20 men and 80 frozen samples
- Generation 2: 40 women and 40 men
From this point on the women of generation 2 could continue to expand the population with the men of generation 1 and 2. It is true that a little bit of bad luck could already mess up the system, but being on the safe side it seems like:
A spaceship with 20 women and a freezer full of sperm is likely enough to start a growing population.”
So how does this pertain to our joke? In all of these situations the studies are searching for genetically diverse colony. This means that they will avoid incest to maintain the best genes. On our lovely island of Santa Rosalia this is not a problem. Though incest holds many problems medically (not to mention morally) it is only considered such if within the close family. Children borne of even first cousin relations are much healthier than parent-child or sibling sired children. These parings aren’t ideal, but they are not as genetically taboo as one might think. Reports have found that children of cousins are only slightly more likely than those of unrelated couples to have cystic fibrosis, mental retardations, and birth defects. How would this continue over a million years? I am unsure, but any unhealthy offspring will be eaten by killer whales so they won’t pass those genes down.