not necessarily in the correct manner (such abandoning their own tools to do so. availability of stones and nuts. Some as placing a nut on top of two stones). It is most likely to be in this period of scientists have claimed this to be proof Those that fail to succeed by the age of observation that juveniles learn the most of culture in wild animals; nature takes around seven apparently never acquire efficient hammer-anvil combinations. on another supposedly uniquely human the skill later in life. Further studies characteristic. To study how these cultural This suggests that have shown the differences arise researchers at the there may exist a chimps to select Bossou site laid out two new types of To list but a hilariouslysensitive period particularly effective nuts, not local to the area, and recorded named few there’s the for learning and stone tools (from the chimpanzees’ reactions to them. It was ant-dip, the algae-scoop, the that perhaps you those provided by discovered that the younger the chimp, the leaf-cushion, the fly-whisk, can’t teach an old researchers) on the more interest they showed towards the the pestle-pound, the leafchimp new tricks. basis of a variety of novel nuts, and the more eager they were sponge and the nasal-probe factors including to watch older individuals attempting to Extensive studies its characteristics crack them. Surprisingly, one adult female on the developmental stages of this (material, size and weight)and portability chimp immediately started successfully behaviour suggest that chimpanzees rely and the hardness of the nut to be cracked. cracking the new nuts, with an efficiency mainly on social influences in a system For example, individuals preferred to use not seen in the others. This lead the of ‘education by master-apprentice’, with stones made of granite rather than the scientists to conclude that she had long the details established through individual softer quartz and would even discard a ago emigrated from a region where the trial and error. An infant remains close to tool, or alter its function, if it fractured. nuts were found locally and so was adept its mother until approximately four years at cracking them. These observations old, providing the youngster with ample Regional Specialities suggest that the spread of such cultural opportunity to scrutinize its mother’s nutdifferences relies cracking. During this period, mothers It is only in the on immigration, tolerate their young interacting with their Bossou site that This transmission invention and stones and even eating the nut kernel chimpanzees use predominantly flows social transmission. they have just cracked open. However, movable anvil downwards, from the This transmission the infant’s own nut-cracking attempts stones. Other West elders to the youngsters, predominantly are never directly reinforced with food African groups and horizontally through a flows downwards, and years of unsuccessful trying precede seem to use only community, mainly relying from the elders to their own successful nut-crack. In fact fixed anvils, such on curious juveniles to the youngsters, and researchers have stressed that young as tree roots or pick up the new skill horizontally through chimpanzees are driven not simply to rocky outcrops. a community, obtain food, but also to imitate their Eastern and Central mainly relying on mother’s (and later their peers’) actions. African chimpanzees use no such curious juveniles to pick up the new skill. percussive technology With age, juvenile chimpanzees leave at all, despite the Primat-Archae-Anthrop-ology? their mothers and start observing other nut-crackers in their group. These Behaviour does not fossilise, but juveniles observe individuals the same the ongoing work in this area gives age or older than themselves, but archaeologists insights into the never younger. A similar age pattern evolutionary processes relating to has been suggested for ‘recycling the emergence of stone technology. events’—when an individual Chimpanzees and humans share many appropriates another ancestral traits, so it is reasonable to chimp’s recently suspect that tool use may be another. abandoned With chimp tool use recognised as stone tools, one of the most advanced seen in sometimes any wild animal population, and with further etho-archaeological studies ongoing, this species may help us to understand the factors that influenced the emergence and development of tool use technologies in our own ancestors—though, thankfully we have moved on from nasalprobes.
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Alex Gwyther is a third-year undergraduate reading Biological Sciences at Magdalen College. Art by Olivia Shipton.