I'm enjoying the new version of Battlestar Galactica. Unlike the original, which was cheezy space opera, this show is the best SF show on TV. Yes, I watched the original when I was 18. I knew it was terrible (and full of bad science) but in the 70s TV SF was extremely rare, and often even worse.

The original show began with Pactrick Macnee narrating an opening "There are those who believe that life here, began out there, with tribes of humans who may have been the forefathers of the Egyptians..." They sought the lost tribe of Earth, and in a truly abyssmal sequel finally came to 1980 Earth, which was of course technologically backward compared to them and unable to help in their fight.

This idea was a common one in science fiction of the 20th century. It was frequent in written SF, and Star Trek twice took it up. In one 60s episode, the Enterprise met Sargon, who claimed to have sewn most of the humanoid races. Spock states this meshes with Vulcan history, but another character says that Humans appear to have evolved on Earth. A later episode of Star Trek: The Next Generation reverses this, and Picard follows clues left in DNA to discover the common ancestry of all the humanoids.

Back in the 60s and 70s, when Battlestar Galactica and Star Trek were written, you could get away with this plot. It had a romantic appeal. While there was tons of evidence, as even Star Trek of the 60s knew, that humans were from Earth, we had not come to the 90s and the DNA sequencer. Today we know we share 25% of our DNA with cabbages. We're descended from a long line in the fossil record that goes back a billion years. If life on this planet was seeded from other planets, it was over a billion years ago. It certainly wasn't during the lifetime of Humanity, and nor were all the animals also seeded here at the same time as we were unless the aliens who did it deliberately created a fake fossil record.

(Of course creationists try very hard to make the case that this could be true, but they don't even remotely succeed. If you think they do have a point, you may want to stop reading. You can read on for more SF theory though.)

Thanks to DNA sequencing, you can no more write a "Humans didn't evolve on Earth" story than you can write a "canal civilizations on Mars" story. Science has caught up.

So that's the challenge to the new Battlestar. It started with the same premise -- the characters believe life evolved on the now ruined planet of Kobol, guided by the Greek gods, and spread out to 12 colonies and also Earth. That belief has to be wrong if they're doing the show right. However, there are alternate explanations:

• The show is set in the far future. An expedition from Earth founded Kobol and took the names of the Greek gods. (In fact, since the colonies are named after constellations seen only from Earth, this makes a fair bit of sense.) When they get to the future, high-tech Earth, it may indeed save them from the Cylons. Or it may have since fallen.
• The show is set in the present, but powerful aliens, who in fact were the Greek gods, transported some people from Earth thousands of years ago to found Kobol. Then the tribes of Kobol advanced far more quickly in technology than we did.
• The show is set in the present. An ancient advanced civilization on Earth, an "Atlantis" if you will, founded Kobol and erased all trace of itself from Earth.

There are hints of this in the show. The Cylons say they know a dark secret about the gods of Kobol. It's part of why they are monotheistic, while the "good guys" are polytheists. We'll have to keep tuned in to find out, which is what they want.

And a final comment on Star Trek. While Star Trek: TNG should have known better than to do a story where all the aliens are cousins of Humans, they were trying to correct another major scientific flaw. For makeup reasons, all the aliens on Star Trek and most other shows are extremely human-looking, with just a few extra bumps or spots. And many of them can interbreed with Humans. This is ridiculous. Any true aliens wouldn't look very human at all. Even cousins of humanity split off hundreds of thousands of years ago and evolving on other planets would look a great deal more different, and would not be able to interbreed. For most animal species, a few thousand generations in an alternate environment on the same planet is enough to speciate, let alone dealing with a completely different planet. If they can interbreed, they split off recently.

(I wished that, when they covered the conception of characters like Spock, Troi and Torres that they had made a point of stating the the conceptions were artificial, with advanced genetic engineering, rather than natural conceptions.)

Battlestar Galactica, to its credit, has no aliens. (In the original Battlestar, the Cylons were an ancient reptilian race, that had been wiped out by their own Robot creations, and the AIs had switched to using a humanoid form because it was superior. Patrick Macnee played an evil godlike being who it seemed, was manipulating the Cylons as their leader and whose race may have been toying with the lesser races for some time.)

I hope Galactica stays without aliens, though they may be tempted to borrow this point from their original and have the gods of Kobol (and of Greece) be aliens.

Updated thoughts: One interesting possibility is they will come to a future Earth which is ruled by AIs, created independently of the Cylons. So the conflict will be not human-vs-cylon, but Earth AIs vs. Colony AIs (Cyclons.)

Another poster presented an interesting cycle theory. Earth created transcendent AIs, and the bio-humans fled to Kobol. There they created AIs, and the bio-humans fled to the 12 colonies. There the 12 colonies created AIs (Cylons) and fled...