endless babble about extraterrestrial life

0. I was depersonalising the other day (if it is that) when I kindof detach from everything and it feels like Im not really there, Im just watching through someone's eyes.
....and I noticed a buzzing sound, instantly I reckoned a fly had been caught in a web, which after I walked over to the window I realised it had, it was stuck there in it's last dying seconds (or perhaps it just starves to death), the spider came out of its front door so to speak, and with front legs crawled it's way casually to it's dinner...It waited next to the struggling fly until after a few minutes it finally submitted...The spider proceeded to wrap it's food, either for preservation for another day, or to protect it from theft/stop it from escaping, Im not sure, to preserve probably lol. Then I thought of these guys' place in the food chain, then had that reoccuring thought "Nature is truly awesome".

1. Life only started on this planet because it could support it. Without meeting a series of requirements it wouldnt be possible, and the requirements are precise. I read (unconfirmed yet) in one sum that there are 10,000 Earth-like planets in the universe capable of supporting life. These days, life has repeatedly been shown to be more adaptable than previously thought, so maybe it's more than that. (The sum of working out how many life-capable planets are out there is known to be a tough bit of maths!)

2. I dont see why our planet's own system of the food chain, with larger animals eating smaller less capable animals, wouldnt natrually occour on other [extrasolar] planets. Predators being at the top, pretty much the best organisms the planet has to offer, in it's stage of evolution. One could guess that extrasolar planets that are life-capable (which Im sure exists) would follow the same pattern.

3. The planet must be inside the habitable "green-zone" of a solar system. The type of star that the system's planets orbit around also changes the distance and 'thickness' of a zone.
Imagine you have a planet like ours, at the same distance from the sun as ours, but the star is a huge [neutron?] star the planet would be burned to a crisp and atmosphere wouldnt form as the huge stars' solar flares would 'rip' it off. So not too cold, not too hot. Another thing-it must have water. I'd guess if it has water, it has an atmosphere. Something the green zone represents is too cold-water will freeze, too hot-water will vapourize.
Some planets are chocked in vapour and deadly gases, with thick dense atmospheres (Venus, Jupiter), and life stands no chance of existing there.

4. It is thought, as far as I know, that the process of evolution would be slower on a colder planet (at the outer edge of a green zone) and happen faster on a warmer planet (inner edge), I heard of "biomechanical" processes that suggest that this is true.
:shrug:

Any astrologists, physicists, biologists, cosmic-geographers, or English teachers that would like to correct me or add anything please do...though Im guessing that somehow there wont be:weep:...or if anyone has thoughts about this sorta thing, or even to tell me to stfu :D

ps.Im not smart but find science very fascinating, I realise all this stuff is well-known within the scientific community and that I have alot to learn...