[robbiep]

Apologies for breaking seveneves for you:

Why do they need to generate artificial Y chromosomes when there is a whole bunch of perfectly good ones in the last man alive who just died with them; and thousands upon thousands in the scattered genetic material in the frozen tin cans floating about in various orbits between earth and the shattered moon? And why does that have to lead to essentially speciation of the survivors?

[ben_w]

The tin cans heavily exposed to radiation? And in direct sunlight so more likely desiccated than frozen? And didn’t that guy just die of cancer? Though I was wondering why they didn’t start collecting semen and egg samples immediately after the total loss of the first samples.

Perhaps I’m misremembering, but I didn’t perceive the description as true speciation, more like socially defined racial groups.