The most important gas is oxygen
Earth
it supports a great diversity of plant and animal life
co2 and o2
compose of gasses
Water
Earth is the only one we know about.
canary
co2 and o2
they will most likely die, since all life needs water and oxygen.carbon dioxide/ etc gasses
the troposphere supports the life.
Earth supports life, because it has oxygen.
Samoa is in South Pacific ocean. It only supports small number of animal life. There are only 2 native mammals in the country which are the lying foxes and bats.