> why did humans evolve to build huge civilizations and spent so much energy on technology, when others species haven't?
In a nutshell -- because humans invented agriculture, which led to ballooning human populations, and then the agriculture at scale required to sustain those populations required centralized laws and control (e.g. enforcing legal contracts around shared irrigation) which is a civilization. And agriculture is so valuable that civilizations use the economic surplus to invent weapons to invade other civilizations, so we jump from food tech to warfare tech.
But agriculture seems to be the main factor. Of course you can go further back and ask why humans invented agriculture where other animals haven't, and it's probably some combination of opposable thumbs and the social intelligence we developed to live in tribes etc. Elephants might have tremendous social intelligence but they don't seem to have the physical dexterity to hoe a field. (There might also be something about physical size, where elephants are too big, so they eat too much relative to what agriculture could produce through their physical output.)
In a nutshell -- because humans invented agriculture, which led to ballooning human populations, and then the agriculture at scale required to sustain those populations required centralized laws and control (e.g. enforcing legal contracts around shared irrigation) which is a civilization. And agriculture is so valuable that civilizations use the economic surplus to invent weapons to invade other civilizations, so we jump from food tech to warfare tech.
But agriculture seems to be the main factor. Of course you can go further back and ask why humans invented agriculture where other animals haven't, and it's probably some combination of opposable thumbs and the social intelligence we developed to live in tribes etc. Elephants might have tremendous social intelligence but they don't seem to have the physical dexterity to hoe a field. (There might also be something about physical size, where elephants are too big, so they eat too much relative to what agriculture could produce through their physical output.)