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Queen Signaling in Social Wasps

  • Statistics Netherlands (CBS)


Social Hymenoptera are characterized by a reproductive division of labour, whereby queens perform most of the reproduction and workers help to raise her offspring. A long-lasting debate is whether queens maintain this reproductive dominance by manipulating their daughter workers into remaining sterile (queen control), or if instead queens honestly signal their fertility and workers reproduce according to their own evolutionary incentives (queen signalling). Here we test these competing hypotheses using data from Vespine wasps. We show that in natural colonies of the Saxon wasp, Dolichovespula saxonica, queens emit reliable chemical cues of their true fertility and that these putative queen signals decrease as the colony develops and worker reproduction increases. Moreover, these putative pheromones of D. saxonica show significant conservation with those of Vespula vulgaris and other Vespinae, thereby arguing against fast evolution of signals as a result of a queen-worker arms race ensuing from queen control. Lastly, levels of worker reproduction in these species correspond well with their average colony kin structures, as predicted by the queen signalling hypothesis but not the queen control hypothesis. Altogether, this correlative yet comprehensive analysis provides compelling evidence that honest signalling explains levels of reproductive division of labour in social wasps. This article is protected by copyright. All rights reserved.
-4.0 -2.0 0.0 2.0 4.0 6.0
PC2 (15.2%)
PC1 (42.8%)
Reproductive workers
Sterile workers
-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4
Ovary Score
0.4 0.5 0.6 0.7 0.8 0.9 1.0
Colony Stage
0 1 2 3 4 5 6
0 1 2 3 4 5 6
Variable Estimate p
(Intercep t) 0.50 0.88 0.384
Ovary Score 0.89 5.81
< 0.001 ** *
Variable Estimate p
(Intercept) Q 8.03 3.26
0.00 3 * *
Colony Stage -5.68 -1.79 0.083
Caste RW -8.47 -3.02
0.00 5 * *
Colony Stage * Caste RW 9.62 2.67
0.01 2 *
Variable p
(Intercep t) Q 21.96 2.63
0.013 *
PC1 -3.88 -1.78 0.084
Caste RW -16.06 -1.82 0.078
PC1 * Caste RW 6.89 2.95
0.006 **
Estimate t
Variable p
(Intercept) Q 100.66 5.44
< 0.001 ** *
PC1 -17.87 -3.71
< 0.001 ** *
Caste RW -65.97 -3.38
0.00 2 * *
PC1 * Caste RW 20.17 3.90
< 0.001 ** *
Estimate t
Peak # Component
GLMM: Q vs. SW, p < 0.01
GLMM: RW vs. SW, p < 0.01
Average Percentage
PC1 loading
PC2 loading
Q vs. SW
RW vs. SW
Q vs. SW
RW vs. SW
Q vs. W - V. crabro
Q vs. W - D. maculata
Q vs. W - V. squamosa
Q vs. W - V. maculifrons
Log2 ratio
1n-C23 >13 >0.3 >3
2 7-,9-,11-MeC23
33-MeC23 0.0 0
b5,x -diMeC23
53,7-diMeC25 0 <-0.3 <-3
d 4-MeC24
7,8 x-C25:1 (+isomer)
10 n-C25
11 7-,9-,11-,13-MeC25
12 5-MeC25
13 3-MeC25
14 5,9-diMeC25
15 n-C26
16 3,9-diMeC25
17 10-,11-,12-,13-MeC26
18 5-MeC26
19 4-MeC26
20,21 x-C27:1 (+isomer)
22 4,y-diMeC26
23 n-C27
24 9-,11-,13-MeC27
25 7-MeC27
26 5-MeC27
27 11,15-diMeC27
28 3-MeC27
29 5,11-diMeC27
30 5,y-diMeC27 + x-C28:1
31 n-C28
32 3,11-, 3,13-diMeC27
33 3,7-diMeC27
34 11-,12-,13-,14-MeC28
35 6-MeC28
36 4-MeC28
37,38 x-C29:1 (+isomer)
39 n-C29
40 9-,11-,13-,15-MeC29
41 7-MeC29
42 5-MeC29
43 9,13-, 11,15-, 13,17-diMeC29
44 3-MeC29
45 5,y-diMeC29
46 3,9-, 3,11-, 3,13-, 3,15-diMeC29
47 3,7-diMeC29
48 12-, 13-, 14-, 15-MeC30
49 4,y-diMeC30
50 x-C31:1
51 unidentified
52 n-C31
53 13-, 15-MeC31
54 11,15-diMeC31
55 3-MeC31 + 7,13-, 7,15-diMeC31
56 5,y-diMeC31
g 13-, 15-MeC33
D. saxonica V. vulgaris Other Vespinae
PCA Log2 ratio Log2 ratio Log2 ratio
... The compounds nonacosane and 3-methylnonacosane, abundant in M. consimilis treated with JH, are considered queen pheromones that are known to suppress worker reproduction (Oliveira et al. 2017). Nonacosane was also the major epicuticular component identified in queens of the Saxon wasp Dolichovespula saxonica (Van Zweden et al. 2013). ...
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When queens of eusocial Hymenoptera mate ≤2 times (assuming equal sperm contributions from males and random sperm use), the workers are more closely related to the queen's sons than to the sons of a randomly chosen worker. This suggests that workers should try to prevent other workers from reproducing, and hence producing sons, in species with queens that mate ≤2 times. It also provides a possible reason for the absence of reproductive workers in many hymenopteran societies. Reproductive harmony may therefore result from lowered relatedness among workers. The necessary behaviors and discriminatory ability to favor queen-produced over worker-produced males are referred to as "worker policing'. Population-genetics simulations of the fate of a "police allele', which confers any marginal increase in policing behavior to the workers carrying it, indicate that such an allele will invade and spread to fixation provided that queens mate two or more times. This conclusion is supported empirically by what is known about queen mating frequency and worker reproduction in the highly eusocial bees and wasps. Societies typically headed by monandrous queens, eg those of the bumblebee Bombus terrestris and stingless bees (Meliponinae), have reproductive workers in queenright colonies; those with polyandrous queens, as in honey bees Apis and some yellowjacket wasps Vespula, do not. -from Author
Four important points in colony development are distinguished: 1) start of egg laying by the queen, leading to the beginning of the eusocial phase, the emergence of the first workers; 2) the switch point, at which the queen switches from laying diploid eggs (producing workers or queens) to the laying of haploid eggs (producing males); 3) onset of queen production reared from diploid eggs; 4) loss of dominance by the queen, expressed by the beginning of aggression on the part of queen and workers, worker oviposition, oophagy and the functional elimination of the queen. -from Authors