DOI: 10.5061/dryad.1zcrjdg27
title: Temporal variability in host availability alters the outcome of competition between two parasitoid species

description: Variability in the availability of resources through time is a common
 attribute in trophic interactions, but its effects on the fitness of
 different consumer species and on interspecific competition between them
 are not clearly understood. To investigate this, we allowed two parasitoid
 species, Trichopria drosophilae and Pachycrepoideus vindemiae, to exploit
 Drosophila host pupae under different temporal variability treatments,
 either on their own or simultaneously. When tested individually (in the
 absence of interspecific competition), both parasitoid species had lower
 fitness when hosts were exposed for a short duration at high density than
 when exposed for a long duration at low density. When both parasitoid
 species exploited hosts simultaneously, interspecific competition
 significantly decreased the number of offspring for both parasitoid
 species. The outcome of this interspecific competition depended on host
 temporal variability, with T. drosophilae or P. vindemiae dominating in
 short and long host exposure treatments, respectively. These results can
 be explained by the combination of host availability and egg load of
 female adult parasitoids. When abundant hosts are provided for a short
 period, the ample mature eggs of the proovigenic T. drosophilae enable
 them to exploit hosts more efficiently than P. vindemiae, which is
 synovigenic. However, P. vindemiae is an intrinsically superior competitor
 and dominates when multiparasitism occurs. Multiparasitism is more
 frequent when hosts are at low levels relative to the egg load of the
 parasitoids. Our results clearly demonstrate that resource temporal
 availability can alter the outcome of competition between consumers with
 different reproductive traits.
description: # Temporal variability in host availability alters the outcome of
 competition between two parasitoid species
 [https://doi.org/10.5061/dryad.1zcrjdg27](https://doi.org/10.5061/dryad.1zcrjdg27) ## Description of the data and file structure ### Files We have submitted our raw data (**Fitness_Data.xlsx, Competition_Data.xlsx, HostHandlingTime_Data.xlsx, OocytesTraits_Data, OvipositionDynamic_Data**). ## Descriptions ### **Fitness\_Data** * *Numbers of parasitoids emerged from host pupae*: The number of adults of *Trichopria drosophilae* or *Pachycrepoideus vindemiae* emerging when host pupae were exposed to parasitoids separately. * *Numbers of pupae were parasitized by parasitoids*: The number of pupae parasitized by *Trichopria drosophilae* or *Pachycrepoideus vindemiae* when host pupae were exposed to parasitoids separately. * *Num_Hosts/day*: The number of host pupae were exposed to parasitoids per day. * *Days*: Day XX when host pupae were exposed to parasitoids. * *Num_T.d*: The number of adults of *Trichopria drosophilae* emerged from host pupae. * *Num_P.v*: The number of adults of *Pachycrepoideus vindemiae* emerged from host pupae. * *8p/d_1*: 8 host pupae were exposed to parasitoids per day, '1' after the horizontal line indicates the first individual, the same for *20p/d_1* and *40p/d_1*. * *20p/d_1*: 20 host pupae were exposed to parasitoids per day. * *40p/d_1*: 40 host pupae were exposed to parasitoids per day. * *Num_Pupae_one T.d*: The number of host pupae with one *Trichopria drosophilae* larva * *Num_Pupae_more than one T.d*: The number of host pupae with more than one *Trichopria drosophilae* larva * *Num_Total*: The total number of host pupae that were parasitized by parasitoids. * *Num_Pupae_one P.v*: The number of host pupae with one *Pachycrepoideus vindemiae* larva * *Num_Pupae_more than one P.v*: The number of host pupae with more than one *Trichopria drosophilae* larva ### **Competition\_Data** * *Numbers of parasitoids emerged from host pupae*: The number of adults of *Trichopria drosophilae* and *Pachycrepoideus vindemiae* emerged when host pupae were exposed to parasitoids simultaneously. * *Numbers of pupae were parasitized by parasitoids*: The number of pupae parasitized by *Trichopria drosophilae* and *Pachycrepoideus vindemiae* when host pupae were exposed to parasitoids simultaneously. * *Num_Pupae_T.d and P.v*: The number of host pupae with *Trichopria drosophilae* and *Pachycrepoideus vindemiae* larva. The meanings of other variables in *Competition_Data* are the same as in *Fitness_Data*. ### **HostHandingTime\_Data** * *Individuals*: Individual XX of parasitoids. * *Time_s_Drumming*: The time that parasitoids spend on drumming a host pupa (s). * *Time_s_Drilling*: The time that parasitoids spend on drilling a host pupa (s). * *Time_s_Oviposition*: The time that parasitoids spend on injecting an egg into a host pupa (s). * *Time_s_Total*: The total time that parasitoids spend on an oviposition bout (s). ### **OocytesTraits\_Data** * *Len_mm_Eggs*: The length of eggs in ovaries of newly emerged parasitoids (mm). * *Num_Eggs*: The number of eggs in the ovaries of newly emerged parasitoids. ### **OvipositionDynamic\_Data** * *Num_Wasps*: The number of adults of parasitoid wasps emerged from 50 host pupae. * *Num_Eggs_Remain*: The number of mature eggs left in the ovaries of parasitoids were dissected 15 days later. * *Num_Total*: Lifetime fecundity of an individual parasitoid.