DOI: 10.5061/dryad.3n5tb2rrb
title: Data from: Dynamics of insects and their facultative defensive endosymbiotic bacteria: A simulation model

description: Most insects harbour endosymbionts that modify their physiology,
 reproductive mode, and ecology. One fascinating case is in aphids, which
 host endosymbionts that protect them against attacks from parasitoids.
 These symbionts are transmitted maternally with high fidelity but can also
 be transmitted horizontally from infected to uninfected hosts. Since
 symbionts can confer resistance to their host against parasitoids, levels
 of symbiont infection should rapidly spread to fixation. This is not the
 case in most aphid populations that have been studied. Furthermore, the
 defensive effect of symbionts has been thought to reduce the efficacy of
 biological control against crop pests, although this has never been
 properly quantified. We developed a Monte Carlo simulation model to
 examine changes in levels of endosymbiont infection in an insect
 population in the presence of parasitoids attacking them over several
 generations. We also used the model to quantify potential reductions in
 the efficacy of parasitoids in controlling host populations in biological
 control. Results suggest that longevity of parasitoids and the spatial
 aggregation of hosts likely play a major role in the dynamics of symbiont
 infection. This is the first evidence that these ecological parameters are
 potentially important for explaining levels of symbiont infection in
 insect populations.
description: # Data from: Dynamics of insects and their facultative defensive
 endosymbiotic bacteria: A simulation model The codes are written in a
 standard ANSI C language and can be compiled with all standard compilers,
 linking them with the standard math library. A typical way to compile them
 could be: cc main_simulation.c -lm -o main_simulation Launching these
 codes with the "-h" argument provides the following help lines:
 usage: ./main_simulation value1 value2 value3 value4 value5 value6 value7
 where value1, value2, value3, value4, value5 value6 and value7 are: For
 value1: Average longevity of the females. For value2: Average fecundity of
 the females. For value3: Cost of infection by a symbiont. For value4:
 Level of horizontal transmission. For value5: Aggregation level of
 infected aphids. For value6: Level of protection conferred by the
 symbionts. For value7: File name to store results. usage:./main_simulation
 -h gives this help This should be self-understandable. For example, if
 there is the need to launch a code with: 1. Average longevity of the
 females = 100. 2. Average fecundity of the females = 150. 3. Cost of
 infection by a symbiont = 0.3. 4. Level of horizontal transmission = 0.8.
 5. Aggregation level of infected aphids = 0.04. 6. Level of protection
 conferred by the symbionts = 1.0. Then a corresponding instruction can be:
 ./main_simulation 100 150 0.3 0.8 0.04 1 output_file In which
 "output_file" (the last argument) is the name of the file in
 which the results will be stored. Two different codes are provided here.
 The first one is called "main_simulation" and runs the standard
 simulation described in the MS. The second one is called
 "simulation_biological_control" and treats the special case
 computing the efficacy of biological control. Running the first code
 returns results in the form of a table with 100 lines corresponding to 100
 independent replicates, and seven columns. The first six columns give the
 values of the six parameters used in the model, in the same order as they
 are indicated in the command line to launch the simulations. The last
 column gives the proportion of hosts infected at the end of each
 simulation. The second code requests an additional parameter entered at
 the first position, which corresponds to the proportion of hosts infected
 in the population. Running this second code returns the results in exactly
 the same form, with the additional parameter mentioned in the output and
 with the last column giving the estimated efficacy of biological instead
 (see the paper entitled "Dynamics of insects and their facultative
 defensive endosymbiotic bacteria: A simulation model" (Wajnberg &
 Cônsoli, 2024) Ecology and Evolution, 14, e70676, for additional
 explanations).