Scientists have discovered that chimpanzees employ a degree of engineering when making their tools, deliberately choosing materials based on their flexibility and mechanical properties. The research, carried out by a multidisciplinary team of scientists from the University of Oxford, the Max Planck Institute for Evolutionary Anthropology, the Jane Goodall Institute in Tanzania, the University of Algarve, the University of Porto and the University of Leipzig, has shown that chimpanzees regularly choose plant materials that create more flexible tools for termite fishing. This finding could help us understand how early humans developed their tool-making capabilities.