I am considering specifically multiple intelligent species that all evolved on the same planet, and whether it is plausible that they will end up in a multi-species society or whether one species will conquer and exterminate all others.
Let intelligence describe the conjunction of these traits:
- Tool use
- Transfer of information among individual and across generations, allowing the accumulation of knowledge
- For the sake of argument, presumable self-awareness
I worry that the coexistence of multiple intelligent species is impossible because of these reasons:
- Ancient Homo Sapiens exterminated all other intelligent hominids, suggesting that xenophobia and xenocide amongst intelligent animals is plausible. (Though the extent of intelligence of these other hominids are questionable)
- According to the competitive exclusion principle, multiple species competing in the same niche will be eventually culled to one single species. It might be the case that all intelligent species effectively occupy the same, though likely broad niche.
- The numerous intelligent species, if developing separately, probably will not do so at the same rate, so that one will be more technologically advance than another when two encounters. An analogue of the American-Indian war may ensue, either exterminating the weaker species or reduce them to a status not unlike zoo animals, maybe literally.
Are there factors that may rescue the fragile coexistence of multiple intelligent species? or perhaps I mistook in my reasoning. If possible, what kind of environmental and historical coincidences may facilitate the coexistence of multiple intelligent species native to the same planet?