Individual differences in boldness influence patterns of social interactions and the transmission of cuticular bacteria among group-mates.
Despite the importance of host attributes for the likelihood of associated microbial transmission, individual variation is seldom considered in studies of wildlife disease. Here, we test the influence of host phenotypes on social network structure and the likelihood of cuticular bacterial transmission from exposed individuals to susceptible group-mates using female social spiders (Stegodyphus dumicola). Based on the interactions of resting individuals of known behavioural types, we assessed whether individuals assorted according to their behavioural traits. We found that individuals preferentially interacted with individuals of unlike behavioural phenotypes. We next applied a green fluorescent protein-transformed cuticular bacterium,Pantoeasp., to individuals and allowed them to interact with an unexposed colony-mate for 24 h. We found evidence for transmission of bacteria in 55% of cases. The likelihood of transmission was influenced jointly by the behavioural phenotypes of both the exposed and susceptible individuals: transmission was more likely when exposed spiders exhibited higher 'boldness' relative to their colony-mate, and when unexposed individuals were in better body condition. Indirect transmission via shared silk took place in only 15% of cases. Thus, bodily contact appears key to transmission in this system. These data represent a fundamental step towards understanding how individual traits influence larger-scale social and epidemiological dynamics.
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA cnk21@pitt.edu.
Carl N
CN
Keiser
BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA.
Noa
N
Pinter-Wollman
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
David A
DA
Augustine
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
Michael J
MJ
Ziemba
BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA.
Lingran
L
Hao
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
Jeffrey G
JG
Lawrence
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA 93106, USA.
Jonathan N
JN
Pruitt
D000818:Animals; D005260:Female; D020636:Pantoea / Q000302:isolation & purification; D010641:Phenotype; D047011:Silk; D012919:Social Behavior; D013112:Spiders / Q000382:microbiology* / Q000502:physiology*
D047011:Silk
assortativity; bacterial transmission; boldness; social network analysis; social spider; transmission heterogeneity