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damienpaul
2004-Feb-19, 12:11 PM
Hi again folks,

Just a simple question...it seems it may be inevitable that humans will start to live other planets/moons....no doubt that even with biodomes etc, our bodies will adpat to the new conditions....how many generations do folks reckon it'll take before significant change is noted, and perhaps how long until a new 'species' emerges?

GOURDHEAD
2004-Feb-19, 01:22 PM
Forced speciation by genetic engineering will happen much sooner than that evolving from mutually isolating environments. Some of the forced speciation will be driven by our desire to occupy ever wider ranges of conditions we encounter.

Since our species, though it has a lot of improving to do in this area, tends to care for those who would otherwise fall by the wayside and allows them to reproduce, they aren't eliminated from the gene pool. This tendency prolongs the interval required to achieve speciation.

Guest
2004-Feb-19, 01:56 PM
Rapid speciation can and does happen in nature. However, as Gourdhead pointed out, I believe that currently, humans have self-evolved far enough that we can continue our own evolution independent of natural evolution. In this regard, one would assume that at most, it would take a few generations to achieve the desired speciation capable of thriving in the new environment.

This brings about many consequences, which after pondering, may preclude the possibility of it happening at all.

devilmech
2004-Feb-19, 01:57 PM
errr... above post is mine. Keep forgetting to log in :rolleyes:

damienpaul
2004-Feb-20, 09:58 AM
So essentially we can 'manufacture' our adaptation to the surrounding environment - whereever that environment may be....do folks see it possible for species in contact to be becoming species in conflict?

devilmech
2004-Feb-20, 10:17 AM
hence the last sentence of my first post, which read "This brings about many consequences, which after pondering, may preclude the possibility of it happening at all. "

GOURDHEAD
2004-Feb-20, 12:23 PM
The "I" of the beholder sometimes trumps the eye of the beholder. As sorcerers' apprentices we will surely fail to accurately anticipate the detrimental consequences of some of our actions. Conflicts surely will ensue; lets manage them in a civil manner. :rolleyes:

Faulkner
2004-Feb-20, 12:32 PM
This brings about many consequences, which after pondering, may preclude the possibility of it happening at all.

Does "preclude" mean "include" or "exclude"??

TheThorn
2004-Feb-20, 02:53 PM
This is an interesting point. I feel some speculation coming on...

Whether we manage it or whether it happens all on it's own, it almost certainly will happen. It will no doubt be relatively quick, and follow a path that has been seen in other speciation events. And the new species will be God-Awful Ugly in our eyes.

Here's what I see happening: Humans will inhabit some other planet, call it Newplanet. The environment will be different than Earth - far more so than varying environments on Earth are. We may try to control everything and we'll make it survivable, at least, but gravity will be different, and no doubt we'll miss some other things.

Those environmental differences will favour the survival and reproduction of humans with certain genetic traits (who knows what traits, it doesn't matter). Whether we purposely direct this or not, in a few generations, the favoured traits will become established in the population of the new planet. This is still not a new species of human, just a new "race", because individuals can and will interbreed with the "earth stock" if there is a flow of people back and forth between Newplanet and Earth.

But the when individuals from Newplanet have children with partners from Earth, the "hybrids" will be intermediate in type, which will make them less suited for survival in either environment (Earth or Newplanet) than the locals. Therefore they will be less likely to successfully reproduce. So individual Newplaneters and individual Earthers who find themselves attracted to the other "race" may have as many children as people who mate with their own "race", but they will tend to have fewer grandchildren. This is a form of natural selection (called sexual selection) that will favour Newplaneters who find Earthers unattractive, and vice-versa.

Neweathers will fix on some trait (not consciously, but genetically) that distinguishes them from Earthers. It may be one of the traits that were advantageous in their environment, it may be something co-incidental. After a couple of hundred generations or so, all the individual Newearthers will find that particular trait of their "race" highly attractive and the other type repulsive, and the two groups will become genetically isolated. During this process, the trait that is fixed on becomes exaggerated as well, and it works even better if the other group (Earthers) finds this trait repulsive.

After a few thousand more generations of not interbreeding, it may become impossible for them to interbreed. Voila, new species.

This sort of natural selection is well documented as a path to speciation. Of course, it is speculation that it will happen to us in the future.

I'd speculate that it has already happened to us in the recent past, but that is another matter and has nothing to do with space and the universe.

devilmech
2004-Feb-20, 03:14 PM
Originally posted by Faulkner@Feb 20 2004, 12:32 PM

This brings about many consequences, which after pondering, may preclude the possibility of it happening at all.

Does "preclude" mean "include" or "exclude"??
http://dictionary.reference.com/search?q=preclude

damienpaul
2004-Feb-20, 11:52 PM
Here is a question, lets just play the devils advocate, and say tat speciation occurs, what would the characteristics of Martians, Europans, etc be?