Does cooperation mean kinship between spatially discrete ant nests?

TY - JOUR

T1 - Does cooperation mean kinship between spatially discrete ant nests?

AU - Procter, Duncan

AU - Cottrell, Joan

AU - Watts, Kevin

AU - A'Hara, Stuart

AU - Hofreiter, Michael

AU - Robinson, Elva Joan Hilda

N1 - © The Authors, 2016

PY - 2016/12

Y1 - 2016/12

N2 - Eusociality is one of the most complex forms of social organization, characterized by cooperative and reproductive units termed colonies. Altruistic behavior of workers within colonies is explained by inclusive fitness, with indirect fitness benefits accrued by helping kin. Members of a social insect colony are expected to be more closely related to one another than they are to other conspecifics. In many social insects, the colony can extend to multiple socially connected but spatially separate nests (polydomy). Social connections, such as trails between nests, promote cooperation and resource exchange, and we predict that workers from socially connected nests will have higher internest relatedness than those from socially unconnected, and noncooperating, nests. We measure social connections, resource exchange, and internest genetic relatedness in the polydomous wood ant Formica lugubris to test whether (1) socially connected but spatially separate nests cooperate, and (2) high internest relatedness is the underlying driver of this cooperation. Our results show that socially connected nests exhibit movement of workers and resources, which suggests they do cooperate, whereas unconnected nests do not. However, we find no difference in internest genetic relatedness between socially connected and unconnected nest pairs, both show high kinship. Our results suggest that neighboring pairs of connected nests show a social and cooperative distinction, but no genetic distinction. We hypothesize that the loss of a social connection may initiate ecological divergence within colonies. Genetic divergence between neighboring nests may build up only later, as a consequence rather than a cause of colony separation.

AB - Eusociality is one of the most complex forms of social organization, characterized by cooperative and reproductive units termed colonies. Altruistic behavior of workers within colonies is explained by inclusive fitness, with indirect fitness benefits accrued by helping kin. Members of a social insect colony are expected to be more closely related to one another than they are to other conspecifics. In many social insects, the colony can extend to multiple socially connected but spatially separate nests (polydomy). Social connections, such as trails between nests, promote cooperation and resource exchange, and we predict that workers from socially connected nests will have higher internest relatedness than those from socially unconnected, and noncooperating, nests. We measure social connections, resource exchange, and internest genetic relatedness in the polydomous wood ant Formica lugubris to test whether (1) socially connected but spatially separate nests cooperate, and (2) high internest relatedness is the underlying driver of this cooperation. Our results show that socially connected nests exhibit movement of workers and resources, which suggests they do cooperate, whereas unconnected nests do not. However, we find no difference in internest genetic relatedness between socially connected and unconnected nest pairs, both show high kinship. Our results suggest that neighboring pairs of connected nests show a social and cooperative distinction, but no genetic distinction. We hypothesize that the loss of a social connection may initiate ecological divergence within colonies. Genetic divergence between neighboring nests may build up only later, as a consequence rather than a cause of colony separation.

KW - wood ants

KW - social insects

KW - ants

KW - relatedness

KW - kin selection

KW - inclusive fitness

KW - cooperation

KW - altruism

KW - polydomy

KW - social networks

KW - communication

KW - foraging

KW - self-organisation

UR - http://www.scopus.com/inward/record.url?scp=85006010307&partnerID=8YFLogxK

U2 - 10.1002/ece3.2590

DO - 10.1002/ece3.2590

M3 - Article

C2 - 28035273

SN - 2045-7758

VL - 6

SP - 8846

EP - 8856

JO - Ecology and Evolution

JF - Ecology and Evolution

IS - 24

ER -