Intelligence also has costs and has components that have to be invented, which explains why not all species are already human-level smart. One of the questions here is which selection pressures were so especially and exceptionally strong in the case of humans, that humans fell off the cliff.
Intelligence also has costs and has components that have to be invented, which explains why not all species are already human-level smart. One of the questions here is which selection pressures were so especially and exceptionally strong in the case of humans, that humans fell off the cliff.