Untangling the complicated history of Homo sapiens’ evolutionary history is far from a finished project. But recent work lends further support to the notion that among our now-extinct fellow hominins there were plenty of thinking, doing beings.

For example, remarkable finds of tools indicate their manufacture and use by Homo erectus perhaps a million years ago. Similar tools dated to about 130,000 years ago appear as plausibly belonging to Homo neanderthalensis. Some of these latter materials come from locations scattered across the Ionian and Aegean seas, and the sea of Crete – the Mediterranean realms. These clues suggest (in the words of the paleontologists) far greater ‘permeability’ of this region than thought. Hominins were mobile. Although it’s difficult to know exactly where there was open water versus land that long ago – with varying sea levels and climates – the suggestion is that there was deliberate navigation and seafaring across at least the eastern Mediterranean. Staggeringly, researchers are discussing the possibility that at least some of the sailors may have been Neanderthals.

Other discoveries in Africa indicate the possibility of tools produced about 3.3 million years ago, predating the entire Homo genus. Perhaps Australopithecus afarenis (‘Lucy’) was chipping stones with intent. And earlier in 2018 evidence was presented of cave paintings in Spain from 65,000 years ago, pre-dating the current estimates of when Homo sapiens arrived in Europe by about 20,000 years. Who were the early artists? Perhaps Neanderthals.

The bottom line is that for substantial periods of time on Earth there were multiple types of creatures not so very different from us anatomically that also probably thought like us – or at least shared much of our capacity for thought.

That is simultaneously fascinating and weird to contemplate. Imagine a world where there were at least two other human-like species wandering around, building stuff, perhaps talking, and probably making art. While we know that today we occupy a planet with other intelligent species, from apes to dolphins to cephalopods, these are all very distinct from us. No one would walk into a bar and strike up a conversation with an octopus without being aware of its differences. But what about walking into a bar and chatting to a Neanderthal? (I’m not suggesting there were bars 40,000 years ago, although it’s tempting to imagine).

There may be something useful to learn from all of this in terms of our puzzling over the existence of intelligence beyond Earth – life out there in the cosmos. First of all, we perhaps don’t exist at a ‘normal’ period in the recent history of life on Earth. We used to be one of a few intelligent hominin species, now we’re the only one left. That seems both good and bad when it comes to life in the rest of the universe. Perhaps having only one type of apex intelligence is not the norm on a planet, it could be the exception. That’s the good. The bad is that perhaps apex intelligences don’t ever get along well enough to survive together.

But the past variety of two-legged intelligences of Earth could also suggest that our strain of intelligence, our style of cognition, is something that evolution spits out when conditions favor it. In other words, our minds might not be so unusual. Maybe, just maybe, there is convergence in the evolution of technological intelligence.

Most of our projections about how intelligent life, and technological civilizations might operate elsewhere in the universe start with our own trajectory. That’s not unreasonable, it’s the template we know. Except the past couple million years of hominin history suggest that it could be a quirky template. Instead of looking into the future of a single technological intelligence we might want to look at the dynamics of a multi-intelligence civilization. How would things play out differently? What would planetary resources and exploration drivers look like with two or three versions of ‘us’ occupying a world?

Of course, this is awfully tricky because we no longer have a handy Neanderthal around to ask for their opinion. We’re still projecting from our singular strain.

Perhaps though, as we unearth more about our own history and that of our long-gone hominin relatives, we might find some clues.