The Origins of Language Jordan Zlatev

1. Lecture 10 Why language evolved? The Origins of LanguageJordan Zlatev

2. Constraints on explanations • No “future utility” – evolution does not plan ahead! • Should benefit the individual (also), not just the group • Match timeframe and environment: hunter-gatherers, (mostly) on the savannah • Why not in other species? (The “why don’t chimps talk?” test…)

3. Factors as “the main selective pressure” for language • Change in diet: Hunting and provisioning • Change in technology: complex tool-making • Change in sexual system • Change in child care (and growth pattern) • Change in group size • Change in social relations • Machiavellian intelligence (competition) • “Christian” intelligence (co-operation, empathy)

4. Relevant traits: apart from language • Efficient bipedalism, allowing (long distance) running • Brain: three times larger, and at least in part, re-organized (rapid increase with H. erectus) • Larger groups, but still relatively “peaceful” • (Partially) monogamous • Neotony and unusually long childhood, then sudden puberty (with Neanderthals) • “Natural pedagogy” • Technology – complex stone tools (with H. erectus) • Mimesis (imitation and pantomine/gesture)

5. Finally… • There may be other adaptations, less directly related to language, but preparing the (long) road towards it…

6. Hunting (and gathering) • Pro - Important both for hominines and for present hunter gatherers (Kaplan et al 2000) - Increased levels with life in open habitats (also in chimpanzees, baboons) - Requires “quality education” (Roebroeks 2001) - Increased levels of co-operation and possibly division of labor (male/female) - Meat diet matches timeframe for brain growth and stone tools • Con - To a large extent present in chimpanzees (males), possibly for “bonding” - A largely “silent activity” (Dunbar 2003)

7. (Active) scavanging • Pro - Chimpanzees don’t scavange (Plummer & Stanford 2000) - Large carcasses on the savannah – require large groups, scouts, recruitment, displaced communication (Bickerton 2009) - Not a “silent activity” - Meat diet matches timeframe for brain growth and stone tools • Con - Chimpanzees scavange (O’Connell et al. 2002 etc)

8. Tool-making • Con - Chimps and other animals use (and even manufacture) tools too - A “solitary activity” in which language plays little role - Slow rate of change - No clear match between stone industries and species (Davidson 2003) • Pro - Acheuliantools mark a transition in complexity; withH. sapiensa “clear acceleration of the pace of technological and cultural innovation” (:201) - Even if not a direct factor for the evolution of language, a factor for mimesis (Donald 1991) - “Sequential and combinatorial activity” (: 202): an exaptation for communication

9. Sex • Pro - Clearly relevant: “if you don’t reproduce, you are an evolutionary failure” (: 202) - Human reproductive systems are unique for mammals: (partially, serially) monogamous, while maintaining life in (large) groups + paternal provisioning and collaborative hunting => symbolic communication (Deacon 1997) • Con - Communication/language not a matter of sexual selection: clearly functional - Humans and chimps have similar levels of sexual dimorphism - Not obvious that human sexual system is more complex than that of chimps, and could even have been “mainly polygynous in the very recent past” (: 204) – Dupanloup et al. (2003)

10. Child care and teaching • Pro - Unusual growth pattern: neotony, childhood, sudden transition (Bogin 1999) - Parental – and group child care: less (sexual) competition, more social learning - Active teaching: (near) universal, and unique for our species • Con - Cultures reported “without pedagogy” - Why adaptive for language, and not in other species?

11. Social relations • Pro - Large groups: ecologically “good”, but require management of intra-group competition for food and mates - “Solution to the dilemma lies in the evolution of social intelligence” (: 210) > brain growth - Communication required to reduce the “cognitive arms race”, “vocal grooming” (Dunbar 1996) - Motivation to provide information :“reputation” and social status are important for individual fitness (Dessalles 2004) • Con - Vocal grooming: “pleasant but meaningless noices” (Bickerton 2002) - More emphasis on “politics” – competition and “reciprocal altruism” rather than (true) empathy

12. Other (non “crackpot”) factors • Childhood play: animals play, but not “symbolically” • Singing: a factor in the transition from mimesis/gesture to speech (Burling 2005) • Narratives: all cultures have stories and most “myths”, and these require an elaborate, sequential, semiotic system (Donald 1991) • Visual art: not a cause, but not an obvious consequence of language either – still, an index of cultural (and cognitive) complexity

13. Conclusion: no single cause, and hence explanation • A combination of factors (and theories) is necessary in order to explain the multiple ape-human differences, and their interrelation, such as a “scenario” relating: • Bipedalism • Complex social life • Intersubjectivity (empathy, normativity) • Mimesis (in skill and communication) • Speech and narratives

14. Bipedalism • Often explained as an adaptation to ecological changes: drier climate, life on the savannah, energy economy… • But the transition to bipedalism occurred earlier than the drying up of Africa around 3.5 million years ago • A possible explanation: apes stand on two legs when they need to “display” > in hominines: also for displaying… sexual parts (clear evidence for sexual selection)

15. Bipedalism and intersubjectivity • Freeing of the hands for other tasks (carrying, tool making, gesturing) • Changes in the birth canal: immature infants, need for longer parental care • Exaptation: more social learning (and play) for children • Adaptation: longer childhood, teaching • Selection for good “mothers and others” (Hrdy 2009): empathy and intersubjectivity • Selection for …“love” (Fisher, Maturana)

16. Complex social life and mimesis • Living in larger groups: negative “side effects”: intra-group competition • Vocal grooming, “song”: affiliation (Dunbar) • Male hunting and provisioning, and food distribution => origin of “marriage”, a binding social contract (Deacon) • Selection pressures for mimetic skills: tool-use, and social learning • Exaptation for communication: representational gestures • Recruitment using displaced communication (Bickerton)

17. Speech and narrative • Vocal communication • More efficient than whole-body • Vocal control trained independently by song? • Narratives • A “selective pressure” for the cultural evolution of languages – the complexities of grammar are most functional for relating multiple propositions and discourse referents