Transmission mode and distribution of parasites among groups of the social lizard Egernia stokesii.
We explored patterns of infection of three apicomplexan blood parasites with different transmission mechanisms in 46 social groups across seven populations of the Australian lizard, Egernia stokesii. There was higher aggregation of infections within social groups for Hemolivia, transmitted by ticks, and Schellackia, either tick-transmitted or directly transmitted from mother to offspring, than for Plasmodium, with more mobile dipteran vectors. Prevalence was not related to group size, proximity to other groups or spatial overlap with adjacent groups for any of the parasites. However, for Hemolivia, groups with higher levels of relatedness among adults had higher parasite prevalence. Living in social groups leads to higher risk of infection for parasites with low transmission mobility. An unanswered question is why so few lizard species tolerate these risks to form stable social aggregations.
School of Biological Sciences, Flinders University of South Australia, GPO Box 2100, Adelaide, SA 5001, Australia.
Stephanie S
SS
Godfrey
C Michael
CM
Bull
Kris
K
Murray
Michael G
MG
Gardner
D000818:Animals; D001315:Australia; D001522:Behavior, Animal; D056890:Eukaryota / Q000302:isolation & purification*; D005843:Geography; D008116:Lizards / Q000469:parasitology* / Q000502:physiology; D008297:Male; D015995:Prevalence; D011529:Protozoan Infections, Animal / Q000453:epidemiology / Q000469:parasitology* / Q000635:transmission*; D012919:Social Behavior