Environmental Biology of Fishes

, Volume 94, Issue 2, pp 457–463 | Cite as

The offspring size/fecundity trade-off and female fitness in the Atlantic molly (Poecilia mexicana, Poeciliidae)

  • Rüdiger Riesch
  • Martin Plath
  • Ingo Schlupp


Across a variety of taxa, large offspring have been demonstrated to have a fitness advantage over smaller offspring of the same species. However, producing large offspring often comes at the cost of having to produce fewer young, and the payoff (and thus, evolutionary outcome) of this trade-off is expected to vary between environments. Atlantic mollies (Poecilia mexicana: Poeciliidae, Teleostei), inhabiting a sulfidic cave and various non-sulfidic surface habitats in Tabasco (Mexico), are reproductively isolated and evolved divergent female life-history traits: females of the cave ecotype produce considerably fewer, but larger offspring. Stressful (sulfidic) environments may favor the production of larger offspring, as they are better able to cope with chemical stressors. It remains to be determined though if increased offspring survival outweighs the fitness cost of producing fewer but larger offspring even under benign laboratory conditions. We tested 30-day newborn survival of offspring from wild-caught P. mexicana females from diverging populations in a low-density, no predation, no cannibalism, and ad-libitum-food, benign laboratory environment. Survival rates were highly skewed towards larger cave molly offspring; however, surface molly females still had a higher fitness than cave molly females in terms of higher total numbers of surviving offspring. Our study provides evidence for an innate fitness advantage of larger cave molly offspring. Furthermore, the observed differences in life-history strategies could promote further divergence and reproductive isolation among these ecotypes of P. mexicana, because cave molly females immigrating into the adjacent surface habitats would most likely be selected against.


Cave fish Ecological speciation Extremophile teleost Immigrant fitness Local adaptation Offspring size/number trade-off 



We thank J. Curtis for help with fish care, T. J. Colston for help in the field, and the Mexican Government (Permiso de Pesca de Fomento: DGOPA.06192.240608.-1562) for kindly providing permits. We appreciate the support rendered to this project by F.J. García de León, and R. Brian Langerhans helped improve a previous version of this manuscript. The experiments comply with the current laws on animal experimentation of the United States of America (AUS-IACUC approved protocol: R06-026). Funding came from the National Science Foundation of America (DEB-0743406).


  1. Bashey F (2006) Cross-generational environmental effects and the evolution of offspring size in the Trinidadian guppy Poecilia reticulata. Evolution 60:348–361PubMedGoogle Scholar
  2. Bashey F (2008) Competition as a selective mechanism for larger offspring size in guppies. Oikos 117:104–113CrossRefGoogle Scholar
  3. Bierbach D, Klein M, Sassmannshausen V, Schlupp I, Riesch R, Parzefall J, Plath M (2012) Divergent evolution of male aggressive behaviour: another reproductive isolation mechanism in extremophile poeciliid fishes? Internat J Evol Biol (special edition: Mechanisms of Speciation)Google Scholar
  4. Conover WT, Iman RL (1982) Analysis of covariance using the rank transformation. Biometrics 38:715–724PubMedCrossRefGoogle Scholar
  5. Einum S, Fleming IA (2004) Environmental unpredictability and offspring size: conservative versus diversified bet-hedging. Evol Ecol Res 6:443–455Google Scholar
  6. Froese AD, Burghardt GM (1974) Food competition in captive juvenile snapping turale, Chelydra serpentina. Anim Behav 22:735–740CrossRefGoogle Scholar
  7. Godfray HCJ (1995) Evolutionary theory of parent-offspring conflict. Nature 376:133–138PubMedCrossRefGoogle Scholar
  8. Gordon MS, Rosen DE (1962) A cavernicolous form of the Poeciliid fish Poecilia sphenops from Tabasco, México. Copeia 1962:360–368CrossRefGoogle Scholar
  9. Horstkotte J, Riesch R, Plath M, Jäger P (2010) Predation by three species of spiders on a cave fish in a Mexican sulphur cave. Bull Brit Arachnol Soc 15:55–58Google Scholar
  10. Hubbs C (1991) Intrageneric “cannibalism” in Gambusia. Southwest Nat 36:153–157CrossRefGoogle Scholar
  11. Hutchings JA (1991) Fitness consequences of variation in egg size and food abundance in brook trout Salvelinus fontinalis. Evolution 45:1162–1168CrossRefGoogle Scholar
  12. Janzen FJ, Warner DA (2009) Parent-offspring conflict and selection on egg size in turtles. J Evol Biol 22:2222–2230PubMedCrossRefGoogle Scholar
  13. Kelley JL (2008) Assessment of predation risk by prey fishes. In: Magnhagen C, Braithwaite VA, Forsgren E, Kapoor BG (eds) Fish behaviour. Science, Enfield, pp 269–301Google Scholar
  14. Klaus S, Plath M (2011) Predation on a cave fish by the freshwater crab Avotrichodactylus bidens (Bott, 1969) (Brachyura: Trichodactylidae) in a Mexican sulfur cave. Crustaceana 84:411–418CrossRefGoogle Scholar
  15. Lloyd DG (1987) Selection of offspring size at independence and other size-versus-number strategies. Am Nat 129:800–817CrossRefGoogle Scholar
  16. Olivier A, Kaiser H (1997) A comparison of growth, survival rate, and number of marketable fish produced of swordtails, Xiphophorus helleri Heckel (Family Poeciliidae), between two types of culture systems. Aquacult Res 28:215–221CrossRefGoogle Scholar
  17. Parzefall J (1979) Zur Genetik und biologischen Bedeutung des Aggressionsverhaltens von Poecilia sphenops (Pisces, Poeciliidae). Z Tierpsychol 50:399–422CrossRefGoogle Scholar
  18. Pianka ER (1976) Natural selection of optimal reproductive tactics. Am Zool 16:775–784Google Scholar
  19. Plath M, Hauswaldt JS, Moll K, Tobler M, García de León FJ, Schlupp I, Tiedemann R (2007) Local adaptation and pronounced genetic differentiation in an extremophile fish, Poecilia mexicana, from a Mexican cave with toxic hydrogen sulfide. Mol Ecol 16:967–976PubMedCrossRefGoogle Scholar
  20. Plath M, Hermann B, Schröder C, Riesch R, Tobler M, García de León FJ, Schlupp I, Tiedemann R (2010a) Locally adapted fish populations maintain small-scale genetic differentiation despite perturbation by a catastrophic flood event. BMC Evol Biol 10:256PubMedCrossRefGoogle Scholar
  21. Plath M, Riesch R, Oranth A, Dzienko J, Karau N, Schießl A, Stadtler S, Wigh A, Zimmer C, Arias-Rodriguez L, Schlupp I, Tobler M (2010b) Complementary effects of natural and sexual selection against immigrants maintains differentiation between locally adapted fish. Naturwissenschaften 97:769–774PubMedCrossRefGoogle Scholar
  22. Plath M, Riesch R, Culumber Z, Streit B, Tobler M (2011) Giant water bug (Belostoma sp.) predation on a cave fish (Poecilia mexicana): effects of female body size and gestational state. Evol Ecol Res 13:133–144Google Scholar
  23. Reznick D, Endler JA (1982) The impact of predation on life history evolution in Trinidadian guppies (Poecilia reticulata). Evolution 36:160–177CrossRefGoogle Scholar
  24. Reznick D, Bryga H, Endler JA (1990) Experimentally induced life-history evolution in a natural population. Nature 346:357–359CrossRefGoogle Scholar
  25. Riesch R, Tobler M, Plath M, Schlupp I (2009b) Offspring number in a livebearing fish (Poecilia mexicana, Poeciliidae): reduced fecundity and reduced plasticity in a population of cave mollies. Environ Biol Fish 84:89–94CrossRefGoogle Scholar
  26. Riesch R, Plath M, García de León FJ, Schlupp I (2010a) Convergent life-history shifts: toxic environments result in big babies in two clades of poeciliids. Naturwissenschaften 97:133–141PubMedCrossRefGoogle Scholar
  27. Riesch R, Oranth A, Dzienko J, Karau N, Schießl A, Stadler S, Wigh A, Zimmer C, Arias-Rodriguez L, Schlupp I, Plath M (2010b) Extreme habitats are not refuges: poeciliids suffer from increased aerial predation risk in sulfidic, southern Mexican habitats. Biol J Linn Soc 101:417–426CrossRefGoogle Scholar
  28. Riesch R, Plath M, Schlupp I (2010c) Toxic hydrogen sulfide and dark caves: life-history adaptations in a livebearing fish (Poecilia mexicana, Poeciliidae). Ecology 91:1494–1505PubMedCrossRefGoogle Scholar
  29. Riesch R, Plath M, Schlupp I, Marsh-Matthews E (2010d) Matrotrophy in the cave molly: an unexpected provisioning strategy in an extreme environment. Evol Ecol 24:789–801CrossRefGoogle Scholar
  30. Riesch R, Plath M, Schlupp I (2011a) Toxic hydrogen sulphide and dark caves: pronounced male life-history divergence among locally adapted Poecilia mexicana (Poeciliidae). J Evol Biol 24:596–606PubMedCrossRefGoogle Scholar
  31. Riesch R, Plath M, Schlupp I (2011b) Speciation in caves: experimental evidence that permanent darkness promotes reproductive isolation. Biol Lett, in pressGoogle Scholar
  32. Sinervo B, Daughty P, Huey RB, Zamudio K (1992) Allometric engineering: a causal analysis of natural selection on offspring size. Science 258:1927–1930Google Scholar
  33. Smith CC, Fretwell SD (1974) The optimal balance between size and number of offspring. Am Nat 108:499–506CrossRefGoogle Scholar
  34. Stibor H (1992) Predator induced life-history shifts in a freshwater cladoceran. Oecologia 92:162–165CrossRefGoogle Scholar
  35. Tessier AJ, Consolatti NL (1989) Variation in offspring size in Daphnia and consequences for individual fitness. Oikos 56:269–276CrossRefGoogle Scholar
  36. Tobler M (2009) Does a predatory insect contribute to the divergence between cave- and surface-adapted fish populations? Biol Lett 5:506–509PubMedCrossRefGoogle Scholar
  37. Tobler M, Schlupp I (2010) Differential susceptibility to food stress in neonates of sexual and asexual mollies (Poecilia, Poeciliidae). Evol Ecol 24:39–47CrossRefGoogle Scholar
  38. Tobler M, Schlupp I, Heubel KU, Riesch R, García de León FJ, Giere O, Plath M (2006) Life on the edge: hydrogen sulfide and the fish communities of a Mexican cave and surrounding waters. Extremophiles 10:577–585PubMedCrossRefGoogle Scholar
  39. Tobler M, DeWitt TJ, Schlupp I, García de León FJ, Herrmann R, Feulner PGD, Tiedemann R, Plath M (2008) Toxic hydrogen sulfide and dark caves: Phenotypic and genetic divergence across two abiotic environmental gradients in Poecilia mexicana. Evolution 62:2643–2659PubMedCrossRefGoogle Scholar
  40. Tobler M, Riesch R, Tobler CM, Schulz-Mirbach T, Plath M (2009b) Natural and sexual selection against immigrants maintains differentiation among micro-allopatric populations. J Evol Biol 22:2298–2304PubMedCrossRefGoogle Scholar
  41. Trivers RL (1974) Parent-offspring conflict. Am Zool 14:249–264Google Scholar
  42. Weeks SC, Gaggiotti OE (1993) Patterns of offspring size at birth in clonal and sexual strains of Poeciliopsis (Poeciliidae). Copeia 1993:1003–1009CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Department of ZoologyUniversity of OklahomaNormanUSA
  2. 2.Department of Biology & W. M. Keck Center for Behavioral BiologyNorth Carolina State UniversityRaleighUSA
  3. 3.Abteilung für Ökologie & EvolutionJ. W. Goethe Universität Frankfurt am MainFrankfurt a. M.Germany

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