Post on 09-Jan-2016
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Jewel Wasp BiologyJewel Wasp Biology
Kadeen JohnsKadeen Johns
Barry K. RhoadesBarry K. Rhoades
Nasonia VitripennisNasonia Vitripennis Life Life CycleCycle
Characteristics of Characteristics of Nasonia Nasonia vitripennisvitripennis Wasps are parasitoid on fly pupariaWasps are parasitoid on fly puparia
Females oviposit up to 40 eggsFemales oviposit up to 40 eggs Several host species, including Several host species, including Sarcophaga bulattaSarcophaga bulatta Complete metamorphosis with ~14 day developmental cycleComplete metamorphosis with ~14 day developmental cycle Jewel wasps are haplodiploid – gender determined by ploidyJewel wasps are haplodiploid – gender determined by ploidy
Flightless, haploid males have shortFlightless, haploid males have short wings - mate at eclosion sitewings - mate at eclosion site Diploid females have longer wings, Diploid females have longer wings,
larger bodies – locate and oviposit hostslarger bodies – locate and oviposit hosts Mating takes place immediately after eclosionMating takes place immediately after eclosion Three different stock eye colors - wild, scarlet, and oysterThree different stock eye colors - wild, scarlet, and oyster
Nasonia vitripennis Nasonia vitripennis ReproductionReproduction
Female sex determination of offspringFemale sex determination of offspring
Haplodiploid genetics of eye colorHaplodiploid genetics of eye colorMated female(stores sperm)
Diploid fertilized egg Haploid unfertilized egg
Female offspring Male offspring
Female Phenotypes:Wild Scarlet Oyster+.+/+.+ +.st/+.st oy.+/oy.++.+/+.st+.+/oy.++.st/oy.+
Male Phenotypes:Wild Scarlet Oyster+.+ +.st oy.+
Maternal Determination of Maternal Determination of Progeny Gender in Progeny Gender in Nasonia Nasonia
vitripennisvitripennis Female stores sperm after mating in spermathecaFemale stores sperm after mating in spermatheca Female can deposit either fertilized or unfertilized eggsFemale can deposit either fertilized or unfertilized eggs Female can detect prior ovipositions into host puparium Female can detect prior ovipositions into host puparium
and control sex ratio of offspring (F1) during oviposition and control sex ratio of offspring (F1) during oviposition For single oviposition, females mate with brothers upon For single oviposition, females mate with brothers upon
eclosioneclosion Ideal F1 sex ratio differs depending on oviposition Ideal F1 sex ratio differs depending on oviposition
exclusivity and sequential order – facultative sex ratio exclusivity and sequential order – facultative sex ratio adjustmentadjustment First wasp (primary oviposition) -> predominantly female First wasp (primary oviposition) -> predominantly female
progeny – maximizes # of F2 secnd generation female offspringprogeny – maximizes # of F2 secnd generation female offspring Subsequent wasps (superoviposition) -> relatively more males – Subsequent wasps (superoviposition) -> relatively more males –
outcompete primary wasp’s few male F1 progeny for outcompete primary wasp’s few male F1 progeny for reproductive access to F1 femalesreproductive access to F1 females
Multiple female wasps directly competing -> relative number of Multiple female wasps directly competing -> relative number of male progeny should increase with number of competing waspsmale progeny should increase with number of competing wasps
Distinguishing Females Distinguishing Females from Malesfrom Males
sorting pupae – to isolate virgin females
Distinguishing Females Distinguishing Females from Malesfrom Males
Distinguishing Females Distinguishing Females from Malesfrom Males
Eye Color VariantsEye Color Variants
Facultative Sex Ratio Facultative Sex Ratio AdjustmentAdjustment
Based on Oviposition Based on Oviposition SequenceSequence
Offspring
Male Female M/F Ratio
1st Wasp 78 225 0.35
2nd Wasp 86 73 1.18
Single fly puparium exposed sequentially to 2 female waspsSingle fly puparium exposed sequentially to 2 female wasps Day1 – female wasp 1, Day 2 – female wasp 2Day1 – female wasp 1, Day 2 – female wasp 2 Purebred eyecolor stocks used to determine offspring parentagePurebred eyecolor stocks used to determine offspring parentage Balanced design with repetitionsBalanced design with repetitions
W1S2 x 4, S1W2 x4 – 4 groupsW1S2 x 4, S1W2 x4 – 4 groups O1S2 x 4, S1O2 x 4 – 3 groupsO1S2 x 4, S1O2 x 4 – 3 groups
Data included:Data included: if and only if female progeny from both parental stocksif and only if female progeny from both parental stocks 16 out of 56 fly puparia -> 462 wasps16 out of 56 fly puparia -> 462 wasps 22 = 36.5, = 36.5, d.f.d.f. = 1, p < .001 = 1, p < .001
Offspring Sex Ratio for Primary vs. Secondary Oviposition
00.20.40.6
0.81
1.21.4
1st wasp 2nd wasp
Oviposition Order
Off
spri
ng
Sex
Rat
io -
#
Mal
es/#
Fem
ales
Facultative Sex Ratio Facultative Sex Ratio Adjustment Based on Adjustment Based on Female CompetitionFemale Competition
Offspring
Male Female M/F Ratio
1 Wasp 95 150 .63
2 Wasps 157 115 1.37
4 Wasps 234 147 1.59
8 Wasps 249 173 1.44
Single fly puparium exposed to 1 or more female Single fly puparium exposed to 1 or more female wasps concurrentlywasps concurrently
1, 2, 4, or 8 female wasps – 4 day exposure1, 2, 4, or 8 female wasps – 4 day exposure Repetitions – 7 sets x 4 conditions Repetitions – 7 sets x 4 conditions Data included:Data included:
if and only if female progeny eclosedif and only if female progeny eclosed 23 out of 28 fly puparia -> 1320 wasps23 out of 28 fly puparia -> 1320 wasps 22 = 26.1, = 26.1, d.f.d.f. = 3, p < .001 = 3, p < .001 Offspring Sex Ratio with
Oviposition Competition
0.00
0.50
1.00
1.50
2.00
1 Wasp 2 Wasps 4 Wasps 8 Wasps
Number of Ov ipositing Wasps
Off
sp
rin
g S
ex
R
ati
o -
# M
ale
s/#
Fe
ma
les