Query: How many years ago did hunting-gatherers start specializing in their collection practices?
Context: Starting at the transition between the Middle to Upper Paleolithic period, some 80,000 to 70,000 years ago, some hunter-gatherers bands began to specialize, concentrating on hunting a smaller selection of (often larger) game and gathering a smaller selection of food. This specialization of work also involved creating specialized tools, like fishing nets and hooks and bone harpoons.