Human’s technological ascent began in earnest in what is known as the Neolithic Period (“New Stone Age”). The invention of polished stone axes was a major advance that allowed forest clearance on a large scale to create farms. This use of polished stone axes increased greatly in the Neolithic, but were originally used in the preceding Mesolithic in some areas such as Ireland. Agriculture fed larger populations, and the transition to sedentism allowed simultaneously raising more children, as infants no longer needed to be carried, as nomadic ones must. Additionally, children could contribute labor to the raising of crops more readily than they could to the hunter-gatherer economy.