Sure but you're thinking current humanity and contrary to modern times, there were plenty of civilisations that did engage in long term infrastructure in the pa

Sure but you're thinking current humanity and contrary to modern times, there were plenty of civilisations that did engage in long term infrastructure in the past. We're talking millions of years in the future and assuming "we" are still around, I doubt that a 21st century layperson would be able to deduce that they ever stemmed from the same genus, never mind species - even assuming no genetic engineering or cyborgs. Life extension is also likely going to play a major factor in the future and it's a lot harder to dismiss the merits of long term thinking when it's a very likely possibility that you will be around to experience the consequences of your current short-sightedness.