Future Space War

In article , says...
In article ,
Nick Maclaren wrote:
| Not in the long run -- not enough genetic variety (mitochondrial DNA in
| particular comes only from the mother)...

Yes, with the probable exception of your remark about mitochondrial
DNA. Were it inherited solely from the mother...

It is. Mitochondria have their own genetic material -- they are almost
certainly the distant descendants of symbiotic bacteria -- and there are
none in a sperm cell. Check any textbook on the subject if you don't
believe me. (In fact, there's active research in tracing back the details
of mankind's origins using genetic comparisons of mitochondrial DNA, which
is hugely easier because that DNA doesn't get *mixed* every generation.)

The fact that mitochondria DNA doesn't usually mix rather shows that you
don't need much if any diversity there. Each individual's mitochondria,
and the DNA they contain, are mostly descended from a single line
already.

Still, sperm isn't the optimum genetic cargo. You'd want to carry
frozen sperm, eggs, and embryos. For the female participants, you'd
want to allow them to fertilize one or two of their own eggs as a reward
for birthing all those genetic strangers.

I can't even guess what the minimum number for a viable society
would be, but my guess is that even a few thousand would work only
with STRONG selection for effectiveness. Current social structures
would just not cut the ice.

There is plenty of past experience with isolated human populations in that
size range, although more people would certainly be better. Social
structure is certainly an issue, but not an unsolvable one.


I think that this is much harder than the genetic diversity issue. All
those babys are going to create their own social structure. I suspect
it will be weird.

Marc

In article ,
Russell Wallace wrote:
On Wed, 31 Mar 2004 13:40:13 +1200, Rupert Boleyn
wrote:

That's just plain wrong. Sperm cells have a _lot_ of mitochondria -
they're what provide a cell with energy, and sperm use a lot of energy
wriggling around. However, for some reason (possibly that they're
'worn out', last I heard no-one really really knows) the sperm's
mitochondria are flagged with a marker that says to a cell's clean-up
machinery 'for disposal'.

The reason is that otherwise the two sets of mitochondria would fight
to the death, weakening the cell. (There's a plant species that fails
to do this with their chloroplasts, with this result.)

While they are so flagged, there is a positive probability
that some mitochondrial DNA will be interchanged with the
egg mitochondria before the disposal. There are know cases
of people having diseases due to mitochondrial DNA which
could only have come from the father.
--
This address is for information only. I do not claim that these views
are those of the Statistics Department or of Purdue University.
Herman Rubin, Department of Statistics, Purdue University
Phone: (765)494-6054 FAX: (765)494-0558

Robert Heinlien, author of the book "Star Ship Troopers" who was I
believe a WW2 Naval Officer, but I expect had alot of experiances with
USMC beach assaults?

Mike


Jukka Koivusaari wrote:

"Henry Spencer" kirjoitti
...
In article ,
Master and Owner, Beryl J. Turner III wrote:
One to consider that a common tactical axiom is that whomever has the
high
ground, has the advantage...

Yes and no and kind of. Consider that there has been little interest in
military occupation of Mount Everest.


It is not overlooking anything , is it?

You put a mass-driver on the moon, calculate the ballistics and wham!

Calculate the energetics instead of the ballistics. Lunar catapults (they
are generally not mass drivers -- that's a specific type of catapult) are
massively overrated as weapons. I'm sorry to shatter illusions, but
Heinlein blew this one badly.

What is a Henlein ?

Their power supplies have to be too big and
the waste heat would be too hard to hide.

Assuming you control the whole Moon, you can have 3000km of rock between you
and the observer . Besides if somebody on Earth spots it , so what. You have
3 days to scorch their interceptor with dircet energy weapons . And under
lunar conditions even old fashioned AA-guns would provide extremely
effective point defence

--
-JK
http://www.kolumbus.fi/jik/
"Paska on hyvää."
- miljoona kärpästä

Very true. It helps to have people to teach the skills necessary to
survive..

You can only do so much with books and knowing how to read.

Mike

Also it helps to have a voice that is different than the norm, also
explains a number of actors who are love gods..

Mike

Read it again - the book specifically noted that they built (and
later used) a backup catapult, with its own fusion plant, concealed to
avoid bombing by the UN forces. And that the secret weapon remained a
secret long after the war ended.

Which book was this? I've read Starship Troopers and I'm trying to
figure out which of his other ones would be good/similar to that one.

On Sat, 03 Apr 2004 19:45:55 GMT, (Russell
Wallace) carved upon a tablet of ether:

The reason is that otherwise the two sets of mitochondria would fight
to the death, weakening the cell. (There's a plant species that fails
to do this with their chloroplasts, with this result.)

I wondered if there might be some sort of confusion or something. I
had no idea they'd fight, though - this sounds very cool. How do
mitochondria fight? Does having most of the genes for producing
mitochondroa in the nuclear DNA (like humans do, IIRC) make a
difference at all?

--
Rupert Boleyn
"Just because the truth will set you free doesn't mean the truth itself
should be free."

"Ian Stirling" wrote in message
...
In sci.space.tech Roger Moore wrote:
"Ami Silberman" writes:

There are no moon sized asteroids.

Only because anything that big in orbit around the sun is called a
planet
rather than an asteroid. I'll agree, though, that it would be very
difficult for something the size of the moon to hide well enough that we
wouldn't see it until it was just 25 years away. FWIW, NASA has just
announced the discovery of a new object in the Kupier belt that is
estimated to be significantly smaller than the moon and several times
further away than Pluto. I'd expect that we would have caught anything
bigger and closer than that already.

Things can have been further away than pluto for the entire history
of photographic astronamy, and still have periapsis closer in.
It's not inconcievable that something large could have a very long period
and interact with Pluto/Uranus to turn it into a large impactor with only
a few years warning.
Vanishingly unlikely, yes.

Have there been any proposals to stare at Uranus/Pluto/Jupiter/Saturn
looking for gravitational interactions?

It's not even necessary. Go look at the images of Shoemaker-Levy's impact(s)
on Jupiter. A long period comet can easily put paid for us. After all, the
dinosaurs remember...

"Bob Martin" wrote in message
om...
Read it again - the book specifically noted that they built (and
later used) a backup catapult, with its own fusion plant, concealed to
avoid bombing by the UN forces. And that the secret weapon remained a
secret long after the war ended.

Which book was this? I've read Starship Troopers and I'm trying to
figure out which of his other ones would be good/similar to that one.

"The Moon Is A Harsh Mistress"

(Bob Martin) writes:

Read it again - the book specifically noted that they built (and
later used) a backup catapult, with its own fusion plant, concealed to
avoid bombing by the UN forces. And that the secret weapon remained a
secret long after the war ended.

Which book was this? I've read Starship Troopers and I'm trying to
figure out which of his other ones would be good/similar to that one.

"The Moon is a Harsh Mistress." However, it is not "similar" to
"Starship Troopers;" it is basically a re-telling of the American
Revolution (with elements of early Australia), set in the context
of Luna as a penal colony whose residents (both convict and free)
were being ruthlessly exploited by the federated terran governments.


-- Gordon D. Pusch

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