World with no moon

[SA]

What are the consequences?

The world is set within a giant ring, so it has more than enough light at night, but what environmental/ecological effects would the absence of a moon create?

[sparkletwist]

There was actually a documentary on this.

You can watch it on Youtube:
http://www.youtube.com/watch?v=trdoc25q9wY

[Elemental_Elf]

It depends on how much Gravity the Ring provided. If it were great enough, I could see the Ring really replacing the moon. If the gravity was not equivalent then the World would drift along its axis, going in all sorts of weird directions leading to a very chaotic planet that I am sure you are trying to avoid.

Since you probably want a stable world, I can't offer much beyond the fact that tides would most likely be very different. The Ring would, potentially, exert an equal force across the world. With out tides, many of the animals that rely on Tides would obviously not exist in the number they do on Earth, if at all.

Would the Ring be viable during the day? It would stretch across the sky... Speaking of which, would the Ring cast a Shadow? If it did, the affected area would not have plants because Photosynthesis would not be able to occur for long periods of time (assuming the World drifted on its axis, like Earth (meaning seasonal variation)).

Anyways, That's all I can think of for now. :)

[SA]

The ring casts a long and persistent shadow across the world when it lies flat along the plane of its orbit around the sun.  I don't know how long it lasts, but I imagine it will definitely be a defining characteristic of the world.

[Seraph]

It actually might depend on the behavior of the ring in relation to the planet.  Does the ring spin around the world like a hula hoop?  Does it rotate?  How do the [at this point hypothetical] rotations of the planet on its axis and the the ring interact?  Do the rings move with the motion of the planet, such that they remain stationary relative to the planet itself?  If the rings and planet move independently of one another, then the ring might be able to exert a similar effect (at least on the tides) to that of the moon.  If the ring is stationary relative the to planet, then tides would be unaffected by the ring, I think, and without other forces at work there might not be a tide at all.

[Nomadic]

It actually might depend on the behavior of the ring in relation to the planet.  Does the ring spin around the world like a hula hoop?  Does it rotate?  How do the [at this point hypothetical] rotations of the planet on its axis and the the ring interact?  Do the rings move with the motion of the planet, such that they remain stationary relative to the planet itself?  If the rings and planet move independently of one another, then the ring might be able to exert a similar effect (at least on the tides) to that of the moon.  If the ring is stationary relative the to planet, then tides would be unaffected by the ring, I think, and without other forces at work there might not be a tide at all.

Provided the ring wasn't lopsided it wouldn't have enough effect on the oceans to create a discernible tide.

[SA]

I think I conveyed that wrong.  The world is on the inner face of the ring, like Halo.  The picture in the link is a good example.

[Elemental_Elf]

I think I conveyed that wrong.  The world is on the inner face of the ring, like Halo.  The picture in the link is a good example.

If there was no 'core' at the center of the ring, equidistant from all sides of the ring, it would, like a world, naturally drift into different positions (like going from horizontal to vertical and back over the Millenia. The easiest way to stop this is to have a natural pivot on which the Ring could naturally rotate. This could be anything from a massive asteroid to a small planet to a much larger planet. It all depends on how large the Ring is.

[SA]

I'm not worried about the motions of the planet, the reliability of its orbit/rotation or what have you.  All that's covered.  All I really need to know is the consequences of an absent moon on the environment and ecology of a world that is nevertheless stable, healthy, and life-supporting.

Like, what kinds of creatures are affected by a tideless ocean?  How are coastlines affected? What kinds of earth creatures are dependent on moonlight/lunar cycles in some fashion?

[Llum]

Coastal erosion is down, the tide is a massive effect on that. That leaves only wind/rain.

Most of shore animals are effected by the tide, so they're all effectively different and/or obsolete.

Animals that navigate by the moon with have to navigate some other way.