From an evolutionary perspective since primitive hunting required greater physical involvement. Though I'm sure there were early female hunters, men are the ones who are better evolved to be (primitive) hunters while women evolved into a support role. The physical development of men simply lends itself far better to hunting. Generally, men develop denser muscles more quickly, have better night vision, focus on distant objects better, can track moving objects better, and have more euclidean spacial awareness. By contrast, women are more sensitive to smell, are more receptive to touch and pain, have better color vision, navigate based on landmarks and turning and communicate much better. The more interesting question is: Why didn't women evolve to be the dominant, or at least an equal, hunting gender like you observed in other species of mammals? Humans are unique among mammals. Our infants have huge heads relative to their bodies and that doesn't let women birth very many at the same time. Canines and felines have litters. Bears have multiple cubs. Among humans twins are uncommon, triplets more so. But our heads make humans intelligent and savvy planners too, we can craft tools and have enough coordination and strength to launch those tools accurately. But there's a big barrier between babies and competent hunters that we have forgotten about due to modern medicine: high rates of infant mortality and maternal death. High infant mortality and the slow maturation rate of human beings made it certain there had to be many children. The high maternal death rate meant many girls would have to replace the older women of the tribe at a young age. That made women arguably the most valuable asset of a primitive tribe, they made and raised the future of the tribe. That kind of lifestyle isn't conducive to women hunting on a regular basis. Having a 7 month pregnant 16 year old girl gather or cultivate edible plants or cook food is much safer than having the same girl lead a hunt for a woolly mammoth or aurochs.