Twenty five men and twenty five women will take five years to reach another planetary system. They have antisenescence treatments as in some other Anderson futures. They will explore the third planet. If it is uninhabitable, then they will take five years to travel back to Earth. If habitable, they will colonize.
Since the crew are going to pair off, Lindgren stops saying goodbye to her family and spends a day and an evening, then a night, with Reymont to check with him whether he and she can make a couple. I cannot remember from previous readings of the novel whether they stay together throughout what becomes a very long intergalactic, and even intercosmic, voyage.
Unfortunately, we bid farewell to Stockholm at the end of CHAPTER 1 but Anderson has given us way more information about that city than we had any right to expect. Stockholm has become special to me because of Stieg Larsson and it is good to find so much about the city also in Anderson.
25 comments:
https://www.newscientist.com/article/dn1936-magic-number-for-space-pioneers-calculated/
Sorry, this last was from Keith Halperin. I believe Anderson may have used the "50/500 Rule5": 50 to avoid inbreeding, 500 to avoid/minimize genetic drift (https://www.britannica.com/science/minimum-viable-population#ref1215147)
A 50-50 crew is common sense, on a very long voyage and/or possible colonization.
For short voyages, especially under military discipline, a mixed crew with a male majority is doable; the USN and Royal Navy and others do that now.
A mixed crew with a female majority would also be doable, on a long voyage, as would all-male and all-female crews.
A mixed crew with a male majority on a long voyage would be a recipe for madness and murder -- which is precisely what happens with Poul's STARFARERS.
In fact, that was my main boggle at that book; that anyone, even pressed for crew by candidates' reluctance to take such a one-way-time-travel expedition, would make such an elementary mistake.
In AFTER DOOMSDAY, they have all-female and all-male ships, and there's an off-screen mention of a Chinese one with a mixed crew (who might have just hightailed it to some other part of the galaxy, which would be perfectly sensible).
Kaor, Mr. Stirling!
I don't know, I do recall from STARFARERS that the people organizing the "Envoy" expedition had great difficulty finding enough people willing to go on that one way time traveling trip to the future. Given that, and possibly under pressure to either send off the "Envoy" or lose funding, they might have cut some corners as regards the crew. Corner cutting is all too HUMAN a weakness!
Sean
50 would be too few to start a colony? Further ships would be sent if a colony were started? (End a sentence with a question mark and it doesn't commit you to anything!)
Paul:
Referring to the Atomic Rockets site again,
http://www.projectrho.com/public_html/rocket/stellarcolony.php
About a quarter to a third of the way down the page, in a section marked Planting a Colony:
If you do not want to fiddle with math below, the bottom line is as follows. If the colony is to survive inbreeding for up to 100 years, you'll need a minimum of 500 randomly chosen colonists or 50 hand-picked colonists all who are unrelated and of breeding age. If the colony is to have enough genetic diversity to survive for thousands of years, you'll need a minimum of 5000 randomly chosen colonists or 500 hand-picked colonists all who are unrelated and of breeding age. That's if I have not made a silly mistake in arithmetic. Now you can skip to the next section.
It didn't seem to me that Leonora Christine had such a handpicked crew.
David,
Thanks for this!
I think that the answer is that, if the Leonora Christine did colonize, then more colonists would be sent from Earth.
Paul.
Paul, if LC's crew did decide to colonize and gave the "all clear, come on in- the water's fine!" message to Earth, it would be over 70 years before the next bunch showed up. Colony missions need to be considered "one-offs"...
Keith
Keith,
70 years would not be too long in the terms we are talking about. Three or four generations would have grown up but genetic drift would not have progressed too far yet, I don't think.
Paul.
It's perfectly possible to have small founding groups: the Americas may have been colonized by as few as a couple of hundred, and many Polynesian islands had even smaller founders.
You just need to accept "rigorous environmental culling". This could also be done by genetic manipulation, of course.
There can be problems further down the road. The reason the Amerindians and other isolated populations were so vulnerable to Eurasian and African diseases in the Age of Exploration was not just lack of prior exposure, but their high degree of genetic uniformity.
That meant a virus or bacteria could rip through the whole population without meeting much random variation in susceptibility.
I am very impressed by the amount and level of discussion on the blog at present!
Note also that humans as a whole have an exceedingly low level of genetic variation -- there's more among one band of lowland gorillas than in the whole human species. And vastly more among other widespread mammals like wolves.
This argues for at least one and probably more than one genetic bottleneck in our evolutionary history. Certainly there was one when h. erectus developed from the australopithecines.
Our existence is very precarious.
Kaor, Mr. Stirling!
I was surprised to find out, broadly speaking, has such a low level of genetic variability. I did know of the genetic bottlenecks in our remote past. Hmmm, was the Mesopotamian and Biblical Flood stories dim memories of such an event?
Sean
Sean,
I think that the Flood, which is in all the mythologies, represents a very major catastrophe.
Paul.
Kaor, Paul!
I used to think the Mesopotamian/Biblical Flood stories were based simply on a localized catastrophe which first became part of the Mesopotamian myths and then was theologically recast by the Jews. While I still believe in the "recasting" Mr. Stirling's comments makes me think there might well have been a disaster worst than a merely local flood.
Sean
Sean,
Were human beings around during the last Ice Age?
Paul.
Paul: depends what you mean by "Ice Age" and "last", but basically yes.
The Pleistocene -- the period from about 2.5 million to about 12,000 years ago -- was one of repeated glaciations, and humans evolved (mostly in Africa) during that time. 2.5 million years ago was "Lucy", the australopithecine; modern h. sap. sap. emerged about 300,000 years ago; behaviorally modern humans about 80K-60K years ago, on the latest elements.
For a fairly long time h. sapiens sap. overlapped with a bunch of other hominins; neanderthals, denisovians, late erectus, those little hobbit things on Flores.
Currently we're in the Holocene, the "recent" epoch, a rather optimistic designation of a period of unusual climate stability.
Technically we're in an "interglacial" now -- a warm episode in a basically cold period; in fact, we're overdue for a new glaciation, though human actions may have aborted that.
The last 2-3 million years of Earth's history have been exceptionally cold. For most of the time since the emergence of complex life forms, the earth has been much warmer than now, with no glaciers or icecaps and snow only on the top of high-latitude mountains in wintertime.
So could the collective memories that became Flood myths stretch back that far? it is a long time as against written records.
My -guess- would be that they might relate to the massive rise in sea levels at the end of the last glaciation -- that's what drowned the land-bridges between Britain and the Continent and Asia and Alaska. The sea level rose hundreds of feet quite rapidly; probably in no more than a couple of centuries, possibly in less than one.
This was accompanied by radical shifts in precipitation, mostly meaning much more of it, and huge freshwater floods all over the world as ice-dams broke and mountain glaciers melted and retreated. Everything got very wet, very fast.
Whether this is the source of the legend is impossible to tell. But recent research has shown that folk-tales can last a very long time -- for example, "The Smith and the Devil" is demonstrably about 4000 years old at least (that's a minimum figure), dating it to Proto-Indo-European times.
https://royalsocietypublishing.org/doi/full/10.1098/rsos.150645
The end of the last glaciation. I think that's got to be it. The Flood myth is in:
Gilgamesh and the Bible
The Norse creation myth
Greek mythology
Hinduism
no doubt more
Kaor, Paul!
Mr. Stirling's fascinating comments answered your question to me far better than I would have been able to do!
Sean
As an aside, the onset and end of glacial periods now seems to be much more rapid than was believed for a long time.
Like the long struggle to establish continental drift as a reputable theory, it was a product of the triumph of "gradualism" over "catastrophism" in 19th-century geology.
That was necessary -- gradualism was 'more right' and also more productive because it cleared quasi-supernaturalism out of the nascent science -- but the pendulum went rather too far. We now know that both gradual and 'catastrophic' processes are common.
Eg., asteroid impacts and other sudden violent fluctuations are an important part of both geological and biological evolution; the end of the dinosaurian period, for instance.
Kaor, Mr. Stirling!
Larry Niven and Jerry Pournelle's novel LUCIFER'S HAMMER gives us an example of such a "sudden catastrophe" hitting us. A calamitous asteroid impact.
Sean
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