Using tools led to the survival and proliferation of larger-brained humans.

Evidence

Using tools like this one to obtain bone marrow, the most nutritious part of a carcass, they set in train an ancient virtuous circle. This food for body and mind meant that the more cunning, larger-brained individuals would survive to breed larger-brained children, capable in their turn of making ever more complex tools. — Neil MacGregor, A History of the World in 100 Objects, 84

Categorization

• corroborated: 2 independent passages support this claim — Neil MacGregor, A History of the World in 100 Objects, 84
• XREF: connects to: Creating objects allowed humans to adapt and spread geographically. — Neil MacGregor, A History of the World in 100 Objects, 64; Human life began in Africa with stone tools creation. — Neil MacGregor, A History of the World in 100 Objects, 64; Neurological studies show overlapping brain areas for stone tool making and speaking. — Neil MacGregor, A History of the World in 100 Objects, 97 (+1 more)

Broader Connections

• Neurological studies show overlapping brain areas for stone tool making and speaking. #expands (0.75) — Neil MacGregor, A History of the World in 100 Objects, 97