I think life's probably fairly common. Like, bacteria-type stuff, maybe something like moss. I think complex life, and life that lasts as long as that on Earth

I think life's probably fairly common. Like, bacteria-type stuff, maybe something like moss. I think complex life, and life that lasts as long as that on Earth has, is probably extremely rare. There's a lot more that's special about Earth that lets it support large fauna over long spans of time, than just orbital position and basic composition and such. Our weird moon plays a role, tectonic activity is vital, not just for our radiation shield but for the carbon-silicate cycle, Jupiter may even play a pretty big role, and so on. A whole bunch of systems are required to keep conditions on the planet from running away in one direction or another, and it's still come close to getting stuck in some hostile-to-life state, multiple times.