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bioRxiv · 10.1101/470575

Modeling the impact of ex-nido transmitted parasites on ant colony dynamics

Quevillon, L. E.·Hughes, D. P.·Conway, J. M.
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Abstract

Infectious disease outbreaks are a common constraint of group living organisms. Ants (Hymenoptera: Formicidae) live in large, dense colonies and are host to a diverse range of parasites and pathogens, facilitating the possibility of epidemic-induced collapse. However, the majority of parasites infecting ants require a period of development outside of the nest before they can transmit to their next ant host ( ex-nido transmission) and the impact of these parasites on colony dynamics is unknown. Here we develop a mathematical model to assess ant colony dynamics in the presence of such parasites. We find that under field-realistic model conditions, such parasites are unlikely to cause the epidemic collapse of mature ant colonies, unless colony birth rate drops below 0.2328 ants/day. The preponderance of ex-nido transmitting parasites infecting ants and their limited epidemiological impact on colony dynamics may partly explain why collapsed ant colonies are rarely, if ever, observed in natural populations.

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Quevillon, L. E., Hughes, D. P., Conway, J. M.. 2018-11-14. Modeling the impact of ex-nido transmitted parasites on ant colony dynamics. https://doi.org/10.1101/470575

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