title: Reproductive status, endocrine physiology and chemical signaling in the Neotropical, swarm-founding eusocial wasp Polybia micans.
abstract: In the evolution of caste-based societies in Hymenoptera, the classical insect hormones juvenile hormone (JH) and ecdysteroids were co-opted into new functions. Social wasps, which show all levels of sociality and lifestyles, are an ideal group in which to study such functional changes. Virtually all studies on the physiological mechanisms underlying reproductive division of labor and caste functions in wasps have been done on independent-founding paper wasps, and the majority of these studies have focused on species specially adapted for overwintering. The relatively little-studied tropical swarm-founding wasps of the Epiponini (Vespidae) are a diverse group of permanently social wasps, with some species maintaining caste flexibility well into the adult phase. We investigated the behavior, reproductive status, JH and ecdysteroid titers in hemolymph, ecdysteroid content of the ovary and cuticular hydrocarbon (CHC) profiles in the caste-monomorphic, epiponine wasp Polybia micans Ducke. We found that the JH titer was not elevated in competing queens from established multiple-queen nests, but increased in lone queens that lack direct competition. In queenless colonies, JH titer rose transiently in young potential reproductives upon challenge by nestmates, suggesting that JH may prime the ovaries for further development. Ovarian ecdysteroids were very low in workers but higher and correlated with the number of vitellogenic oocytes in the queens. Hemolymph ecdysteroid levels were low and variable in both workers and queens. Profiles of P. micans CHCs reflected caste, age and reproductive status, but were not tightly linked to either hormone. These findings show a significant divergence in hormone function in swarm-founding wasps compared with independently founding ones.
authors.affiliation: Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA kelstrup@sun.ac.za.
authors.forename: Hans C
authors.initials: HC
authors.lastname: Kelstrup
authors.affiliation: Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, Ribeirão Preto, 14049-900 SP, Brazil.
authors.forename: Klaus
authors.initials: K
authors.lastname: Hartfelder
authors.affiliation: Departamento de Biologia da Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, Ribeirão Preto, 14040-900 SP, Brazil.
authors.forename: Fabio S
authors.initials: FS
authors.lastname: Nascimento
authors.affiliation: Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.
authors.forename: Lynn M
authors.initials: LM
authors.lastname: Riddiford
mesh_terms: D000818:Animals; D026461:Ecdysteroids / Q000097:blood*; D005260:Female; D006458:Hemolymph / Q000737:chemistry; D007605:Juvenile Hormones / Q000097:blood*; D010053:Ovary / Q000737:chemistry; D010675:Pheromones / Q000378:metabolism; D012098:Reproduction; D012919:Social Behavior; D014863:Wasps / Q000502:physiology*
chemical_list: D026461:Ecdysteroids; D007605:Juvenile Hormones; D010675:Pheromones
keywords: Challenge hypothesis; Cuticular hydrocarbons; Ecdysteroids; Epiponini; Juvenile hormone; Polistes
references.citation: J Insect Physiol. 2000 Jun 1;46(6):1033-1040
references.pmid: 10802116
references.citation: J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2006 Mar;192(3):315-20
references.pmid: 16283330
references.citation: J Insect Physiol. 2005 Jul;51(7):811-23
references.pmid: 15885700
references.citation: J Chem Ecol. 2007 Jan;33(1):167-81
references.pmid: 17146723
references.citation: Am Nat. 2010 Aug;176(2):123-30
references.pmid: 20515411
references.citation: Insect Biochem Mol Biol. 2002 Feb;32(2):211-6
references.pmid: 11755066
references.citation: J Insect Physiol. 1997 Jun;43(6):541-545
references.pmid: 12770416
references.citation: Evolution. 2014 Apr;68(4):976-86
references.pmid: 24219699
references.citation: Horm Behav. 2013 Jan;63(1):1-4
references.pmid: 22986338
references.citation: J Exp Biol. 2012 Feb 1;215(Pt 3):454-60
references.pmid: 22246254
references.citation: J Insect Physiol. 2003 Mar;49(3):217-22
references.pmid: 12769996
references.citation: Science. 1978 Apr 28;200(4340):441-3
references.pmid: 17757302
references.citation: Nature. 2006 Jan 5;439(7072):76-8
references.pmid: 16397498
references.citation: Mol Cell Endocrinol. 1983 Sep;32(1):27-46
references.pmid: 6628834
references.citation: Science. 2014 Jan 17;343(6168):287-90
references.pmid: 24436417
references.citation: Evol Dev. 2007 Sep-Oct;9(5):499-513
references.pmid: 17845520
references.citation: Proc Natl Acad Sci U S A. 2007 Aug 28;104(35):14020-5
references.pmid: 17704258
references.citation: Curr Biol. 2011 Feb 8;21(3):231-5
references.pmid: 21256023
references.citation: J Comp Physiol A. 1994 Jun;174(6):731-9
references.pmid: 8014920
references.citation: Horm Behav. 2009 Nov;56(5):527-31
references.pmid: 19751736
references.citation: Arch Insect Biochem Physiol. 1993;23(3):147-52
references.pmid: 8347857
references.citation: Proc Biol Sci. 2010 Nov 22;277(1699):3461-7
references.pmid: 20534614
references.citation: Insect Mol Biol. 2005 Jan;14(1):9-15
references.pmid: 15663771
references.citation: Insect Biochem Mol Biol. 2011 May;41(5):283-93
references.pmid: 21277979
references.citation: J Insect Physiol. 2011 Jul;57(7):995-9
references.pmid: 21545803
references.citation: J Exp Biol. 2013 Jan 15;216(Pt 2):181-7
references.pmid: 22972899
references.citation: J Insect Physiol. 2010 Jul;56(7):725-30
references.pmid: 20045002
references.citation: J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2011 Nov;197(11):1063-71
references.pmid: 21773739
references.citation: Arch Insect Biochem Physiol. 1997;35(4):559-83
references.pmid: 9210289
references.citation: J Insect Physiol. 2013 Mar;59(3):339-44
references.pmid: 23247338
references.citation: Insect Biochem Mol Biol. 2007 Aug;37(8):847-54
references.pmid: 17628283
references.citation: Proc Biol Sci. 2002 Feb 7;269(1488):263-70
references.pmid: 11839195
references.citation: Proc Natl Acad Sci U S A. 2005 Mar 1;102(9):3330-5
references.pmid: 15728373