I don’t know nothin’ about nothin’, but it seems to me that Life is made up of cycles. Almost all living creatures rely on those cycles to survive, most obviously the weather, but also the plants that need the seasons to live also create their own lifecycles that the animals rely on.
I’m sure there are thousands of examples of other cycles that fundamentally involve the seasons too.
So how likely is it that other planets in the solar system or the entire galaxy would have seasons? And are seasons absolutely crucial for life to exist or survive, or would life adapt to non-seasonal existence?
Could any life forms at all exist without seasons?
Of all the life forms that exist on earth, which ones (if any) would survive in an environment without seasons?
IANA biologist, but I definitely suspect that the answer to #1 is a big fat yes. Natural selection allows for an amazing amount of variation and adaptation.
As for #2, I’m not so sure. I think there are some types of fish that live so deep underwater that they never see the sun, much less notice the change of seasons. Also, organisms that live for less than one entire season (like flies and maybe bacteria) could probably survive.
And, yes, I’m pretty sure that other planets have days and seasons for the same reasons we do.
Not sure that seasons would really make much of a difference. There are places on Earth that show virtually no change from season to season. I think perhaps there would less of a diversity of life without changing seasons, but I’m just guessing.
One of the planets, Neptune, I think it is, has no day or night, since it’s axis is pointing directly at the sun, whereas the axis of the earth is roughly perpendicular, giving us night and day as it rotates.
There are no “seasons” at the equator , and nevertheless, there’s plenty of life.
The existence of seasons on a planet is dependent on its axial tilt, AFAIK. I wouldn’t know what is the axial tilt of the solar system planets, but I’m pretty certain all of them have such a tilt, hence have seasons (though the lenght of said seasons could vary enormously from one planet to another). Someone aknowledgeable on this topic will certainly give a more accurate answer.
Perhaps they don’t, but they eat things which eat things, which eat things which see the sun (and need it and the energy it provides) . So, ultimately, they’re dependant on it to sustain their life.
Life which is flourishing around the ocean thermal vents could perhaps thrive without the sun, though…
But by your same argument as above to Tjdude, there is still the weather at the equator be taken into account (particularly the extreme kind), which varies on the equator itself, affected by weather patterns all over the world.
I can’t think of any reason you’d need seasons.
Undersea thermal vent communities get along nicely without either seasons, or input from the surface world. It’s probably in that climateless ecosystem that microorganisms survived the Snowball Earth of 600 to 700 million years ago.
I’m sure there are many planets whose axes are fairly perpendicular to their orbits, and don’t have seasons as such. But that doesn’t rule out all kinds of irregular weather variations caused by other factors.
Possibly on one such planet, teeming with life, someone is wondering if life can exist on a hypothetical planet with a tilted axis and seasons.
A planet with its axis in the plane of its orbit has extreme seasons. The axis is pretty much stationary with respect to the fixed stars, so as it orbits, first one pole and then half a year later the other faces the sun, with the sun over the equator in between. The cycle of course takes a full year. Those are about as extreme as seasons can get.
Visualize it by pointing one hand straight ahead to represent one pole, and moving it horizontally around the other hand, representing the sun. Planets like the earth with only a small tilt show the same effect to a lesser degree; our poles get continuous dark or daylight for a relatively short period every year. Those seaons are still pretty extreme.
Compare Earth’s poles to the equator, and then consider the OP.
