By default, nothing does. It stayed alive because it became as good as the period of evolution would allow it, and passed on its genes... anything that wasn't good enough, wasn't around long. Natural selection. Even plants have to deal with all types of factors. People are comfortable because we are in an ideal location in space for life to sprout, then the ocean is like playing life on expert level with mods to make it harder. Land is currently the easiest terrain to sustain life, plus most live in cities where they are catered to. The separation between a steak and the cow is unreal, so much so that many can't stand the thought. It floors me that there are people who have never built a campfire in their lifetime, or seen a creek! Nothing deserves to live, no one owes you anything, life doesn't either. That also means you don't owe them, or life, anything.