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Oecologia

, Volume 102, Issue 3, pp 389–396 | Cite as

The evolution of offspring size and number: a test of the Smith-Fretwell model in three species of crickets

  • Y. Carrière
  • D. A. Roff
Original Paper

Abstract

Most models of parental investment in offspring assume a trade-off between propagule size and number, and an increasing “concave down” function relating offspring fitness to propagule size. In this study, we test these two fundamental assumptions, using three closely related species of crickets, Gryllus firmus, G. veletis, and G. pennsylvanicus. Egg weight, 35-day fecundity and 35-day egg biomass were estimated in a population of each species, and the relationships between these reproductive traits and date of egg laying and body size were estimated. The relationships between egg weight and offspring survival were also sought for eggs buried at different depths, soil moistures, and soil types (G. firmus and G. veletis), as well as in the field (G. pennsylvanicus). A trade-off between egg weight and 35-day fecundity was revealed in a multivariate analysis taking into account among-species variation in egg weight and body size. Independent of the environmental conditions affecting the eggs, a positive correlation existed between the number of larvae that emerged from the soil and propagule weight in each species. Therefore, these findings provide partial support for the assumptions considered in the models mentioned above. A single optimal egg size was favored in two out of the three sets of conditions in which the functions relating egg weight to larval survival could be derived. The conditions encountered by the eggs, however, influenced the average survival of the larvae, as well as the shape of the relationship between egg weight and offspring survival. This suggests that cricket eggs frequently face heterogeneous environments with respect to egg and hatchling survival; the implication of habitat heterogeneity on the evolution of an optimal egg size is considered. The relationships between the reproductive components and female age and size, as well as between egg size and variation in cricket life-history, are discussed in an ecological and evolutionary context.

Key words

Gryllus Fitness function Egg size-fecundity trade-off Optimal propagule size 

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References

  1. Alexander RD, Bigelow RS (1960) Allochronic speciation in field crickets, and a new species, Acheta veletis. Evolution 14: 334–346Google Scholar
  2. Begon M, Parker GA (1986) Should egg size and clutch size decrease with age? Oikos 47:293–302Google Scholar
  3. Berrigan D (1991) The allometry of egg size and number in insects. Oikos 60:313–321Google Scholar
  4. Bradford MJ, Guerette PA, Roff DA (1993) Testing hypothesis of adaptive variation in cricket ovipositor lengths. Oecologia 93: 263–267Google Scholar
  5. Clutton-Brock TH (1991) The evolution of parental care. Princeton University Press, PrincetonGoogle Scholar
  6. Gwynne DT (1984) Courtship feeding increases female reproductive success in bushcrickets. Nature 307:361–362Google Scholar
  7. Harrison RG (1979) Speciation in North American field crickets: evidence from electrophoretic comparisons. Evolution 33: 1009–1023Google Scholar
  8. Jong G de (1993) Covariances between traits deriving from successive allocations of a resource. Funct Ecol 7:75–83Google Scholar
  9. Kaplan RH, Salthe SN (1979) The allometry of reproduction: An empirical view in salamanders. Am Nat 113:671–689Google Scholar
  10. Lack D (1954) Natural regulation of animal numbers. Clarendon Press, OxfordGoogle Scholar
  11. Lande R, Arnold SJ (1983) The measurement of selection on correlated characters. Evolution 37:1210–1226Google Scholar
  12. Lloyd DG (1987) Selection of offspring size at independence and other size-versus-number strategies. Am Nat 129:800–817Google Scholar
  13. Masaki S (1979) Climatic adaptation and species status in the lawn ground cricket. III. Ovipositor length. Oecologia 43:207–219Google Scholar
  14. Masaki S (1986) Significance of ovipositor length in life cycle adaptations in crickets. In: Taylor F, Karban R (eds) The evolution of insect life cycles. Springer, Berlin Heidelberg New York, pp 20–34Google Scholar
  15. Masaki S, Walker TJ (1987) Cricket life cycles. In: Hecht MK, Wallace B, Prance GT (eds) Evolutionary biology, vol 21. Plenum, New York, pp 349–423Google Scholar
  16. McGinley MA (1989) The influence of a positive correlation between clutch size and offspring fitness on the optimal offspring size. Evol Ecol 3:150–156Google Scholar
  17. McGinley MA, Temme DH, Geber MA (1987) Parental investment in offspring in variables environments: theoretical and empirical considerations. Am Nat 130:370–398Google Scholar
  18. Parker GA, Begon M (1986) Optimal egg size and clutch size: effects of environment and maternal phenotype. Am Nat 128: 573–592Google Scholar
  19. Partrige L, Harvey PH (1988) The ecological context of life history evolution. Science 241:1449–1455Google Scholar
  20. Roff DA (1986) The genetic basis of wing polymorphism in the sand cricket, Gryllus firmus and its relevance to the evolution of wing dimorphisms in insects. Heredity 57:221–231Google Scholar
  21. Roff DA (1992) The evolution of life histories. Theory and analysis. Chapman and Hall, New YorkGoogle Scholar
  22. Schluter D (1988) Estimating the form of natural selection on a quantitative trait. Evolution 42:849–861Google Scholar
  23. Sinervo B (1993) The effect of offspring size on physiology and life history. BioScience 43:210–218Google Scholar
  24. Smith CC, Fretwell SD (1974) The optimal balance between size and number of offspring. Am Nat 108:499–506Google Scholar
  25. Stearns SC (1992) The evolution of life histories. Oxford University Press, OxfordGoogle Scholar
  26. Venable DL (1992) Size-number trade-offs and the variation of seed size with plant resource status. Am Nat 140:287–304Google Scholar
  27. Wade MJ, Kalisz S (1990) The cause of natural selection. Evolution 44:1947–1955Google Scholar
  28. Williams GC (1966) Adaptation and natural selection. Princeton University Press, PrincetonGoogle Scholar
  29. Wilkinson L (1989) Systat: The system for statistics. Systat, EvanstonGoogle Scholar

Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  1. 1.Department of BiologyMcGill UniversityMontrealCanada

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