Kinship and density in Vespula germanica (Hymenoptera: Vespidae) drone aggregations

MASCIOCCHI, MAITÉ; ANGELETTI, BÁRBARA; CORLEY, J.C.; MARTINEZ, AS

Conferencia; Animal Behavior Live; 2020

In social insects, whose reproductiveindividuals generally leave the nest for copulation, mechanisms deployed tominimize inbreeding, such as dispersal and avoidance of relatives, areimportant for the success of the population. At the time of leaving the nest,the density of related individuals is high, thus favoring inbreeding and, giventheir sexual determination system (single-locus complementary sexdetermination), the number of infertile triploid males increases. Vespula germanica is an eusocial andpolyandry wasp that has successfully established in different parts of theworld, including the Patagonia Argentina. In this study, we ask whether male wasps display specific aggregationbehavior that promotes genetic diversity. High levels of genetic diversity inmale aggregations could be important to reduce inbreeding, because the highnumbers of individuals in aggregations could decrease the probabilities ofmating with relatives. Our aim was to establish under laboratoryconditions, the effects of relatedness and density in encounters between drones.Based on the assumption that due to the negative effects of inbreeding inhymenopterans, V. germanica droneswill promote genetically-diverse aggregations, we expected to find a lower avoidancethreshold (i.e. a lower number of drones) toward kin than that toward non-kin. Using a 4-way olfactometer, we evaluated the behavior ofdrones towards different densities of individuals (2, 6 and 10 drones), relatedand unrelated. We show that drones avoid aggregating with their nestmates atall densities while non-nestmates are avoided only at high densities. Thissuggests that genetic diversity and density in V. germanica drone aggregations could be regulated through dronebehavior and in the long run minimize inbreeding, thus favoring invasionsuccess. A better understanding of the mechanisms involved in thereproductive process of V. germanicadrones, could be important to integrate it into the management programs of thisproblematic species.@font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:1;mso-generic-font-family:roman;mso-font-pitch:variable;mso-font-signature:0 0 0 0 0 0;}@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:swiss;mso-font-pitch:variable;mso-font-signature:-536859905 -1073697537 9 0 511 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin-top:0cm;margin-right:0cm;margin-bottom:8.0pt;margin-left:0cm;line-height:107%;mso-pagination:widow-orphan;font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES-AR;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-size:11.0pt;mso-ansi-font-size:11.0pt;mso-bidi-font-size:11.0pt;font-family:"Calibri",sans-serif;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES-AR;}.MsoPapDefault{mso-style-type:export-only;margin-bottom:8.0pt;line-height:107%;}div.WordSection1{page:WordSection1;}