- Liittynyt
- 5.10.2006
- Viestejä
- 1 192
Sille on olemassa tieteelliset perusteet, että sisäsiittoisuus on pääosin haitallista jälkeläisille ja että laajempi geenipooli johtaa yleensä terveempiin yksilöihin.
Luen mielelläni lisää.
White flight leaves system segregated by race
WHITE students are fleeing public schools, leaving behind those of Aboriginal and Middle Eastern origin, a secret report by high school principals reveals.
The NSW Secondary Principals Council conducted a confidential survey which raises serious concerns about "white flight" undermining the public education system and threatening social cohesion. Some teachers and principals have described it as "de facto apartheid".
The findings are backed by research from the University of Western Sydney, which has identified evidence of racial conflict in schools in the wake of the Cronulla riots. It also suggests students of Anglo-European descent are avoiding some schools with students of mainly Asian background.
http://en.wikipedia.org/wiki/Space_colonization#Population_size
Population size
In 2002, the anthropologist John H. Moore estimated that a population of 150–180 would allow normal reproduction for 60 to 80 generations — equivalent to 2000 years.
A much smaller initial population of as little as two female humans should be viable as long as human embryos are available from Earth. Use of a sperm bank from Earth also allows a smaller starting base with negligible inbreeding.
Researchers in conservation biology have tended to adopt the "50/500" rule of thumb initially advanced by Franklin and Soule. This rule says a short-term effective population size (Ne) of 50 is needed to prevent an unacceptable rate of inbreeding, while a long‐term Ne of 500 is required to maintain overall genetic variability. The Ne = 50 prescription corresponds to an inbreeding rate of 1% per generation, approximately half the maximum rate tolerated by domestic animal breeders. The Ne = 500 value attempts to balance the rate of gain in genetic variation due to mutation with the rate of loss due to genetic drift.

