Did Venus Have A Moon? Options

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...or two?

http://skytonight.com/news/home/4353026.html

[Guest_Myran_*]

JRehling wrote: ...would we be here as an advanced species to discuss the issue if Earth had Uranus's inclination?.

If one such Earth had the same orbit as it have now, evolution would of course have taken another path and Homo Sapiens are very unlikely to be around. Yet I see no reason why one such alterative Earth not would be host to advanced life.
Half year long periods with sunlight around the clock followed by equally long dark winters are after all the natural state of things!

[tty]

Half year long periods with sunlight around the clock followed by equally long dark winters are after all the natural state of things!

In earlier warmer times when there were forests as far north as Ellesmere land and in inland Antarctica lots of plants and animals apparently did quite well under conditions that approached these, so I can't see any strong reason that "Uranian" climate should prevent advanced life forms from developing.

tty

[JRehling]

In earlier warmer times when there were forests as far north as Ellesmere land and in inland Antarctica lots of plants and animals apparently did quite well under conditions that approached these, so I can't see any strong reason that "Uranian" climate should prevent advanced life forms from developing.

tty

Earth is a biased point whether we can prove that life couldn't have gotten sophisticated on a tilted Earth or not -- the burden of proof is on data being unbiased, not vice versa.

But to get into a bit of detail, if we want to talk about a technological civilization, then there is a need for high-yield food production, which in turn requires plants and animals that can be domesticated. And it's a very small fraction of all plants and animals that can be domesticated -- if you cut the number of available species, you presumably cut the ratio of those that can be domesticated.

For example, there are no plant species native to Canada that could be domesticated for food production, even though Canada has plenty of forests.

This may be like standing farther away from a dartboard: as a matter of principle, there's no reason why you can't hit a bullseye, but it gets less likely.