12,000 years ago a species of hominid, something close to man, but not man, existed in the same world as us. On the island of Flores, now part of Indonesia, small creatures who might have been descendants of Homo erectus, or of some other, unknown, lineage, flourished until nearly the beginning of the Holocene, when the world was almost exactly as it is now. if that figure could be brought down to 9-8kya, which is pefectly possible, then we could be certain that these creatures shared the world with Bronze Age peoples in China and the Near East, with the Sialk of Iran, the Jarmo of Mesopotamia, with the predecessors of the Norte Chico in Peru; with people, that is, who lived in cities, farmed, wrote, manufactured and traded, produced song, dance, painting and sculpture, people who could have studied them and left a written recording of their findings, if they had ever met.
It appears they never did. It seems that the creatures of Flores were alone on their island, perhaps they had to be, they could only survive by being alone. It is unlikely they would have been permitted to share foraging or farming land with Homo sapiens, although it would depend on the exact nature of the two societies at the time of contact. Very little is known about the Flores population.
The most important conclusion to be drawn from all of this is not that there were probably other intelligent species living somewhere in the world in historical times; it is that we are the only intelligent species now living on Earth by the purest accident. Between our and chimpanzee intelligence there is nothing represented(by intelligence it is necessary to understand the ability to manipulate abstract symbols, combined with self-awareness, though probably you can't have the first without the second, making degree of consciousness the main criterion). There is nothing now, but there have been many species closely related to us, in different parts of the world, that were close to us in their ability to understand their own existence, and hence to look for explanations. There has probably been a continuum a from Homo sapiens through hominid ancestors, known and unknown, chimpanzee, gorilla ancestors at least. Where is the limit at which whatever makes us special ceases to matter? I repeat, it is only by the purest chance that we do not have to think about that question.
If we had to consider it, it would change fundamentally the way we see ourselves. And it is not an academic question. As more is learnt and incorporated into general learning (assuming public education does not completely disappear in any meaningful sense) the implications of it will filter through to the minds of peopel generally. It is even possible- though highly improbable now- that we are not the the only intelligent species on the planet. But it is certainly true that, until very recently, we were not.
Namibia, Nambia, whatever
25 minutes ago