well, for one, they have able hands with good grip and yet are not exactly using them to build tools to help them getting food more easily, securing against rivals, getting safer against predators etc
like all other primitive creatures, it's all about survival instincts. No doubt they (and dogs, crows, elephants and obviously apes) have memory and problem-solving skills for immediate problems. But the main issue is that they don't seem to reflect upon their actions, they don't ask questions, either to themselves or their peers. Their behavior is repetitive and reaction-based and although much of human behavior is likewise, humans do think over their steps and missteps and improve upon it - humans can forgive, pity, help others and make ever better tools to face ever new problems. Why are there no animal cities? Why live just to hunt or be hunted? Why no plans about the future? Why no whys?
there's only the now for ever hungry creatures incapable of waking up and realizing they can do better by communicating and to do so they need to speak their minds and ask for other thoughts...