What support life on Earth?

Answer 1

We _EVOLVED_ here. Life on Earth is perfectly suited for life on Earth, because we (and all of our terrestrial cousins) developed to be suited to this planet and not some other one. It's not that "the Earth is a suitable place for life": it's that we're this way because the Earth is the way it is.

I think that some of our scientists are too narrowly focused on finding life "out there" that's similar to life here. "Out there" will have very different conditions, and will probably develop very different sorts of life - life that will be well suited to THOSE planets.

Comment: There's something in that answer, obviously. But the fact that Earth

is the only place we know where there is life, suggests it's got something that

is a bit special.

Oxygen is not required for all life on Earth, but liquid water is.

Also, really extreme temperatures probably are not suitable for life as we know it. I'm sure other people have more ideas on this.

Answer 2

Oxygen in the atmosphere, liquid water, and a nice warm cozy temperature.

Answer 3

Life on Earth depends on many different things. In terms of energy, we (life) get the required energy from the Sun.