Decoupling of Genetic and Cultural Inheritance in a Wild Mammal

TY - JOUR

T1 - Decoupling of Genetic and Cultural Inheritance in a Wild Mammal

AU - Sheppard, Catherine E.

AU - Marshall, Harry H,

AU - Inger, Richard

AU - Thompson, Faye J.

AU - Vitikainen, Emma I. K.

AU - Barker, Sam

AU - Nichols, Hazel J.

AU - Wells, David A.

AU - McDonald, Robbie A.

AU - Cant, Michael A.

PY - 2018/5/24

Y1 - 2018/5/24

N2 - Cultural inheritance, the transmission of socially learned information across generations, is a non-genetic, ‘second inheritance system’ capable of shaping phenotypic variation in humans and many non-human animals[1-3]. Studies of wild animals show that conformity[4, 5] and biases toward copying particular individuals[6, 7] can result in the rapid spread of culturally transmitted behavioural traits and a consequent increase in behavioural homogeneity within groups and populations[8, 9]. These findings support classic models of cultural evolution[10, 11] which predict that many-to-one or one-to-many transmission erodes within-group variance in culturally inherited traits. However, classic theory[10, 11] also predicts that within-group heterogeneity is preserved when offspring each learn from an exclusive role model. We tested this prediction in a wild mammal, the banded mongoose (Mungos mungo), in which offspring are reared by specific adult carers that are not their parents, providing an opportunity to disentangle genetic and cultural inheritance of behaviour. We show using stable isotope analysis that young mongooses inherit their adult foraging niche from cultural role models, not from their genetic parents. As predicted by theory, one-to-one cultural transmission prevented blending inheritance and allowed the stable coexistence of distinct behavioral traditions within the same social groups. Our results confirm that cultural inheritance via role models can promote rather than erode behavioral heterogeneity in natural populations. © 2018 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. See http://creativecommons.org/licenses/by/4.0/

AB - Cultural inheritance, the transmission of socially learned information across generations, is a non-genetic, ‘second inheritance system’ capable of shaping phenotypic variation in humans and many non-human animals[1-3]. Studies of wild animals show that conformity[4, 5] and biases toward copying particular individuals[6, 7] can result in the rapid spread of culturally transmitted behavioural traits and a consequent increase in behavioural homogeneity within groups and populations[8, 9]. These findings support classic models of cultural evolution[10, 11] which predict that many-to-one or one-to-many transmission erodes within-group variance in culturally inherited traits. However, classic theory[10, 11] also predicts that within-group heterogeneity is preserved when offspring each learn from an exclusive role model. We tested this prediction in a wild mammal, the banded mongoose (Mungos mungo), in which offspring are reared by specific adult carers that are not their parents, providing an opportunity to disentangle genetic and cultural inheritance of behaviour. We show using stable isotope analysis that young mongooses inherit their adult foraging niche from cultural role models, not from their genetic parents. As predicted by theory, one-to-one cultural transmission prevented blending inheritance and allowed the stable coexistence of distinct behavioral traditions within the same social groups. Our results confirm that cultural inheritance via role models can promote rather than erode behavioral heterogeneity in natural populations. © 2018 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. See http://creativecommons.org/licenses/by/4.0/

U2 - 10.1016/j.cub.2018.05.001

DO - 10.1016/j.cub.2018.05.001

M3 - Article

SN - 0960-9822

VL - 28

SP - 1846

EP - 1850

JO - Current Biology

JF - Current Biology

IS - 11

ER -