Insect egg size and shape evolve with ecology but not developmental rate


Over the course of evolution, organism size has diversified markedly. Changes in size are thought to have occurred because of developmental, morphological and/or ecological pressures. To perform phylogenetic tests of the potential effects of these pressures, here we generated a dataset of more than ten thousand descriptions of insect eggs, and combined these with genetic and life-history datasets. We show that, across eight orders of magnitude of variation in egg volume, the relationship between size and shape itself evolves, such that previously predicted global patterns of scaling do not adequately explain the diversity in egg shapes. We show that egg size is not correlated with developmental rate and that, for many insects, egg size is not correlated with adult body size. Instead, we find that the evolution of parasitoidism and aquatic oviposition help to explain the diversification in the size and shape of insect eggs. Our study suggests that where eggs are laid, rather than universal allometric constants, underlies the evolution of insect egg size and shape.

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Fig. 1: The shapes and sizes of hexapod eggs.
Fig. 2: The allometric relationship of egg shape and size evolves across insects.
Fig. 3: Developmental features do not co-vary with egg size.
Fig. 4: Shifts in oviposition ecology are associated with changes in egg morphology.

Data availability

The dataset of insect eggs is publicly available at Dryad ( with doi:10.5061/dryad.pv40d2r and has been described elsewhere24. The phylogenetic posterior distributions are provided as Supplementary Information (phylogeny_posterior distribution_misof_backbone.nxs and phylogeny_posterior_distribution_rainford_backbone.nxs).

Code availability

All code required to reproduce the analyses and figures shown here is available at


  1. 1.

    Peters, R. H. The Ecological Implications of Body Size (Cambridge Univ. Press, 1983).

  2. 2.

    Allen, R. M., Buckley, Y. M. & Marshall, D. J. Offspring size plasticity in response to intraspecific competition: an adaptive maternal effect across life-history stages. Am. Nat. 171, 225–237 (2008).

    Article  Google Scholar 

  3. 3.

    Blanckenhorn, W. U. The evolution of body size: what keeps organisms small? Q. Rev. Biol. 75, 385–407 (2000).

    CAS  Article  Google Scholar 

  4. 4.

    Kingsolver, J. G. & Pfennig, D. W. Individual-level selection as a cause of Cope’s rule of phyletic size increase. Evolution 58, 1608–1612 (2004).

    Article  Google Scholar 

  5. 5.

    Stanley, S. M. An explanation for Cope’s rule. Evolution 27, 1–26 (1973).

    Article  Google Scholar 

  6. 6.

    LaBarbera, M. Analyzing body size as a factor in ecology and evolution. Annu. Rev. Ecol. Syst. 20, 97–117 (1989).

    Article  Google Scholar 

  7. 7.

    Chown, S. L. & Gaston, K. J. Body size variation in insects: a macroecological perspective. Biol. Rev. Camb. Philos. Soc. 85, 139–169 (2010).

    Article  Google Scholar 

  8. 8.

    Hinton, H. E. Biology of Insect Eggs vols I–III (Pergammon, 1981).

  9. 9.

    Thompson, D. W. On Growth and Form (Cambridge Univ. Press, 1917).

  10. 10.

    Fox, C. W. & Czesak, M. E. Evolutionary ecology of progeny size in arthropods. Annu. Rev. Entomol. 45, 341–369 (2000).

    CAS  Article  Google Scholar 

  11. 11.

    Berrigan, D. The allometry of egg size and number in insects. Oikos 60, 313–321 (1991).

    Article  Google Scholar 

  12. 12.

    García-Barros, E. Body size, egg size, and their interspecific relationships with ecological and life history traits in butterflies (Lepidoptera: Papilionoidea, Hesperioidea). Biol. J. Linn. Soc. 70, 251–284 (2000).

    Article  Google Scholar 

  13. 13.

    Stoddard, M. C. et al. Avian egg shape: form, function, and evolution. Science 356, 1249–1254 (2017).

    ADS  CAS  Article  Google Scholar 

  14. 14.

    Bernardo, J. The particular maternal effect of propagule size, especially egg size: patterns, models, quality of evidence and interpretations. Am. Zool. 36, 216–236 (1996).

    Article  Google Scholar 

  15. 15.

    Hinton, H. E. Respiratory systems of insect egg shells. Annu. Rev. Entomol. 14, 343–368 (1969).

    CAS  Article  Google Scholar 

  16. 16.

    Legay, J. M. Allometry and systematics of insect egg form. J. Nat. Hist. 11, 493–499 (1977).

    Article  Google Scholar 

  17. 17.

    Blackburn, T. Evidence for a ‘fast-slow’ continuum of life-history traits among parasitoid Hymenoptera. Funct. Ecol. 5, 65–74 (1991).

    Article  Google Scholar 

  18. 18.

    Kratochvíl, L. & Frynta, D. Egg shape and size allometry in geckos (Squamata: Gekkota), lizards with contrasting eggshell structure: why lay spherical eggs? J. Zoological Syst. Evol. Res. 44, 217–222 (2006).

    Article  Google Scholar 

  19. 19.

    Bilder, D. & Haigo, S. L. Expanding the morphogenetic repertoire: perspectives from the Drosophila egg. Dev. Cell 22, 12–23 (2012).

    CAS  Article  Google Scholar 

  20. 20.

    Steele, D. & Steele, V. Egg size and duration of embryonic development in Crustacea. Int. Rev. Gesamten Hydrobiol. Hydrograph. 60, 711–715 (1975).

    Article  Google Scholar 

  21. 21.

    Sargent, R. C., Taylor, P. D. & Gross, M. R. Parental care and the evolution of egg size in fishes. Am. Nat. 129, 32–46 (1987).

    Article  Google Scholar 

  22. 22.

    Maino, J. L. & Kearney, M. R. Ontogenetic and interspecific metabolic scaling in insects. Am. Nat. 184, 695–701 (2014).

    Article  Google Scholar 

  23. 23.

    Iwata, K. & Sakagami, S. F. Gigantism and dwarfism in bee eggs in relation to the modes of life, with notes on the number of ovarioles. Jap. J. Ecol. 16, 4–16 (1966).

    Google Scholar 

  24. 24.

    Church, S. H., Donoughe, S. D., de Medeiros, B. A. S. & Extavour, C. G. A dataset of egg size and shape from more than 6,700 insect species. Sci. Data–0049-y (2019).

  25. 25.

    Misof, B. et al. Phylogenomics resolves the timing and pattern of insect evolution. Science 346, 763–767 (2014).

    ADS  CAS  Article  Google Scholar 

  26. 26.

    Rainford, J. L., Hofreiter, M., Nicholson, D. B. & Mayhew, P. J. Phylogenetic distribution of extant richness suggests metamorphosis is a key innovation driving diversification in insects. PLoS ONE 9, e109085 (2014).

    ADS  Article  Google Scholar 

  27. 27.

    Leiby, R. & Hill, C. The polyembryonic development of Platygaster vernalis. J. Agric. Res. 28, 829–839 (1924).

    Google Scholar 

  28. 28.

    Houston, T. F. Brood cells, life-cycle stages and development of some earth-borer beetles in the genera Bolborhachium, Blackburnium and Bolboleaus (Coleoptera: Geotrupidae), with notes on captive rearing and a discussion of larval diet. Aust. Entomol. 55, 49–62 (2016).

    MathSciNet  Article  Google Scholar 

  29. 29.

    Goldberg, J. et al. Extreme convergence in egg-laying strategy across insect orders. Sci. Rep. 5, 7825 (2015).

    CAS  Article  Google Scholar 

  30. 30.

    Harmon, L. J. et al. Early bursts of body size and shape evolution are rare in comparative data. Evolution 64, 2385–2396 (2010).

    PubMed  Google Scholar 

  31. 31.

    Uyeda, J. C., Hansen, T. F., Arnold, S. J. & Pienaar, J. The million-year wait for macroevolutionary bursts. Proc. Natl Acad. Sci. USA 108, 15908–15913 (2011).

    ADS  CAS  Article  Google Scholar 

  32. 32.

    Cooper, N. & Purvis, A. Body size evolution in mammals: complexity in tempo and mode. Am. Nat. 175, 727–738 (2010).

    Article  Google Scholar 

  33. 33.

    Peters, R. H. & Wassenberg, K. The effect of body size on animal abundance. Oecologia 60, 89–96 (1983).

    ADS  Article  Google Scholar 

  34. 34.

    Sieg, A. E. et al. Mammalian metabolic allometry: do intraspecific variation, phylogeny, and regression models matter? Am. Nat. 174, 720–733 (2009).

    Article  Google Scholar 

  35. 35.

    Polilov, A. A. Small is beautiful: features of the smallest insects and limits to miniaturization. Annu. Rev. Entomol. 60, 103–121 (2015).

    CAS  Article  Google Scholar 

  36. 36.

    Gillooly, J. F., Brown, J. H., West, G. B., Savage, V. M. & Charnov, E. L. Effects of size and temperature on metabolic rate. Science 293, 2248–2251 (2001).

    ADS  CAS  Article  Google Scholar 

  37. 37.

    Felsenstein, J. Phylogenies and the comparative method. Am. Nat. 125, 1–15 (1985).

    Article  Google Scholar 

  38. 38.

    Rensch, B. Histological changes correlated with evolutionary changes of body size. Evolution 2, 218–230 (1948).

    CAS  Article  Google Scholar 

  39. 39.

    Rainford, J. L., Hofreiter, M. & Mayhew, P. J. Phylogenetic analyses suggest that diversification and body size evolution are independent in insects. BMC Evol. Biol. 16, 8 (2016).

    Article  Google Scholar 

  40. 40.

    Gregory, T. R. Coincidence, coevolution, or causation? DNA content, cell size, and the C-value enigma. Biol. Rev. Camb. Philos. Soc. 76, 65–101 (2001).

    CAS  Article  Google Scholar 

  41. 41.

    Gregory, T. R. Animal Genome Size Database. Release 2.0 (2019).

  42. 42.

    Roff, D. A. The evolution of flightlessness in insects. Ecol. Monogr. 60, 389–421 (1990).

    Article  Google Scholar 

  43. 43.

    Whiting, M. F., Bradler, S. & Maxwell, T. Loss and recovery of wings in stick insects. Nature 421, 264–267 (2003).

    ADS  CAS  Article  Google Scholar 

  44. 44.

    Trueman, J., Pfeil, B., Kelchner, S. & Yeates, D. Did stick insects really regain their wings? Syst. Entomol. 29, 138–139 (2004).

    Article  Google Scholar 

  45. 45.

    Stancă-Moise, C. et al. Migratory species of butterflies in the surroundings of Sibiu (Romania). Sci. Pap. Ser. Manage. Econ. Eng. Agric. Rural Dev. 16, 319–324 (2016).

    Google Scholar 

  46. 46.

    Ivanova-Kasas, O. M. in Developmental Systems: Insects vol. 1 (eds Counce, S. J. & Waddington, C. H.) Ch. 5, 243–271 (Academic, 1972).

  47. 47.

    Cooper, N., Thomas, G. H., Venditti, C., Meade, A. & Freckleton, R. P. A cautionary note on the use of Ornstein Uhlenbeck models in macroevolutionary studies. Biol. J. Linn. Soc. 118, 64–77 (2016).

    Article  Google Scholar 

  48. 48.

    Nieves-Uribe, S., Flores-Gallardo, A., Hernández-Mejía, B. C. & Llorente-Bousquets, J. Exploración morfológica del corion en Biblidinae (Lepidoptera: Nymphalidae): aspectos filogenéticos y clasificatorios. Southwest. Entomol. 40, 589–648 (2015).

    Article  Google Scholar 

  49. 49.

    Barata, J. M. S. Morphological aspects of Triatominae eggs. II. Macroscopic and exochorial characteristics of ten species of the genus Rhodnius Stal, 1859 (Hemiptera - Reduviidae) (in Portuguese). Rev. Saude Publica 15, 490–542 (1981).

    CAS  Article  Google Scholar 

  50. 50.

    Iwata, K. The comparative anatomy of the ovary in Hymenoptera (records on 64 species of Aculeata in Thailand, with descriptions of ovarian eggs). Mushi 38, 101–109 (1965).

    Google Scholar 

  51. 51.

    Dutra, V. S., Ronchi-Teles, B., Steck, G. J. & Silva, J. G. Egg morphology of Anastrepha spp. (Diptera: Tephritidae) in the fraterculus group using scanning electron microscopy. Ann. Entomol. Soc. Am. 104, 16–24 (2011).

    Article  Google Scholar 

  52. 52.

    Patterson, D., Mozzherin, D., Shorthouse, D. P. & Thessen, A. Challenges with using names to link digital biodiversity information. Biodivers. Data J. 4, e8080 (2016).

    Article  Google Scholar 

  53. 53.

    Pyle, R. L. Towards a global names architecture: the future of indexing scientific names. ZooKeys 550, 261–281 (2016).

    Article  Google Scholar 

  54. 54.

    Rees, J. A. & Cranston, K. Automated assembly of a reference taxonomy for phylogenetic data synthesis. Biodivers. Data J. 5, e12581 (2017).

    Article  Google Scholar 

  55. 55.

    Hinchliff, C. E. et al. Synthesis of phylogeny and taxonomy into a comprehensive tree of life. Proc. Natl Acad. Sci. USA 112, 12764–12769 (2015).

    ADS  CAS  Article  Google Scholar 

  56. 56.

    GBIF. GBIF: The Global Biodiversity Information Facility (2018).

  57. 57.

    Clark, J. The capitulum of phasmid eggs (Insecta: Phasmida). Zool. J. Linn. Soc. 59, 365–375 (1976).

    Article  Google Scholar 

  58. 58.

    Markow, T. A., Beall, S. & Matzkin, L. M. Egg size, embryonic development time and ovoviviparity in Drosophila species. J. Evol. Biol. 22, 430–434 (2009).

    CAS  Article  Google Scholar 

  59. 59.

    Glöckner, F. O. et al. 25 years of serving the community with ribosomal RNA gene reference databases and tools. J. Biotechnol. 261, 169–176 (2017).

    Article  Google Scholar 

  60. 60.

    Quast, C. et al. The SILVA ribosomal RNA gene database project: improved data processing and web-based tools. Nucleic Acids Res. 41, D590–D596 (2013).

    CAS  Article  Google Scholar 

  61. 61.

    Yilmaz, P. et al. The SILVA and “all-species Living Tree Project (LTP)” taxonomic frameworks. Nucleic Acids Res. 42, D643–D648 (2014).

    CAS  Article  Google Scholar 

  62. 62.

    Pruesse, E., Peplies, J. & Glöckner, F. O. SINA: accurate high-throughput multiple sequence alignment of ribosomal RNA genes. Bioinformatics 28, 1823–1829 (2012).

    CAS  Article  Google Scholar 

  63. 63.

    Smith, S. A. & Brown, J. W. Constructing a broadly inclusive seed plant phylogeny. Am. J. Bot. 105, 302–314 (2018).

    Article  Google Scholar 

  64. 64.

    Jetz, W., Thomas, G. H., Joy, J. B., Hartmann, K. & Mooers, A. O. The global diversity of birds in space and time. Nature 491, 444–448 (2012).

    ADS  CAS  Article  Google Scholar 

  65. 65.

    Ronquist, F. et al. MrBayes 3.2: efficient Bayesian phylogenetic inference and model choice across a large model space. Syst. Biol. 61, 539–542 (2012).

    Article  Google Scholar 

  66. 66.

    Maino, J. L., Pirtle, E. I. & Kearney, M. R. The effect of egg size on hatch time and metabolic rate: theoretical and empirical insights on developing insect embryos. Funct. Ecol. 31, 227–234 (2017).

    Article  Google Scholar 

  67. 67.

    Beaulieu, J. M., O’Meara, B. C. & Donoghue, M. J. Identifying hidden rate changes in the evolution of a binary morphological character: the evolution of plant habit in campanulid angiosperms. Syst. Biol. 62, 725–737 (2013).

    Article  Google Scholar 

  68. 68.

    Harmon, L. J., Weir, J. T., Brock, C. D., Glor, R. E. & Challenger, W. GEIGER: investigating evolutionary radiations. Bioinformatics 24, 129–131 (2008).

    CAS  Article  Google Scholar 

  69. 69.

    Pennell, M. W., FitzJohn, R. G., Cornwell, W. K. & Harmon, L. J. Model adequacy and the macroevolution of angiosperm functional traits. Am. Nat. 186, E33–E50 (2015).

    Article  Google Scholar 

  70. 70.

    Revell, L. J. phytools: an R package for phylogenetic comparative biology (and other things). Methods Ecol. Evol. 3, 217–223 (2012).

    Article  Google Scholar 

  71. 71.

    Rabosky, D. L. Automatic detection of key innovations, rate shifts, and diversity-dependence on phylogenetic trees. PLoS ONE 9, e89543 (2014).

    ADS  Article  Google Scholar 

  72. 72.

    Rabosky, D. L. et al. Bamm tools: an R package for the analysis of evolutionary dynamics on phylogenetic trees. Methods Ecol. Evol. 5, 701–707 (2014).

    Article  Google Scholar 

  73. 73.

    Paradis, E., Claude, J. & Strimmer, K. APE: analyses of phylogenetics and evolution in R language. Bioinformatics 20, 289–290 (2004).

    CAS  Article  Google Scholar 

  74. 74.

    Pinheiro, J. et al. nlme: linear and nonlinear mixed effects models. R package version 3.1-117 (2014).

  75. 75.

    Revell, L. J. Phylogenetic signal and linear regression on species data. Methods Ecol. Evol. 1, 319–329 (2010).

    Article  Google Scholar 

  76. 76.

    Tung Ho, L. s. & Ané, C. A linear-time algorithm for Gaussian and non-Gaussian trait evolution models. Syst. Biol. 63, 397–408 (2014).

    Article  Google Scholar 

  77. 77.

    Beaulieu, J. M., Jhwueng, D.-C., Boettiger, C. & O’Meara, B. C. Modeling stabilizing selection: expanding the Ornstein–Uhlenbeck model of adaptive evolution. Evolution 66, 2369–2383 (2012).

    Article  Google Scholar 

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This work was supported by the National Science Foundation (NSF) under grant no. IOS-1257217 to C.G.E., NSF GRFP DGE1745303 to S.H.C. and by a Jorge Paulo Lemann Fellowship to B.A.S.d.M. from Harvard University. We thank members of the Extavour laboratory and B. Farrell, C. Dunn, D. McCoy, D. Rice, A. Kao, E. Kramer, J. Boyle, L. Bittleston, M. Srivastava, M. Johnson, P. Wilton, R. Childers and S. Prado-Irwin for discussion, and the Ernst Mayr Library at the Museum of Comparative Zoology at Harvard, and specifically M. Sears, for assistance in gathering references.

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Nature thanks Clay Cressler and the other anonymous reviewer(s) for their contribution to the peer review of this work.

Author information




S.H.C. and S.D. conceived the project and generated the dataset. S.H.C. performed statistical analyses. B.A.S.d.M. performed phylogenetic analyses. All authors contributed to experimental design, interpretation and writing.

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Correspondence to Samuel H. Church or Cassandra G. Extavour.

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Supplementary information

Supplementary Information

This document contains Supplementary Methods, Supplementary Figures S1-S24, and Supplementary Tables S1-S22. These provide additional methodological details, a more complete description of the diversity of insect eggs, ancestral state reconstructions, and evolutionary model fitting results.

Reporting Summary

Supplementary Information

This file contains the Egg Dataset Bibliography. This document is a list of the 1,756 published sources that were used to generate the assembled dataset of insect egg traits.

Supplementary Information

This nexus file contains 100 phylogenetic trees randomly sampled from the posterior distribution, assembled using the Rainford et al. 2014 (ref. 26 in the main text) phylogeny as a backbone.

Supplementary Information

This nexus file contains 100 phylogenetic trees randomly sampled from the posterior distribution, assembled using the Misof et al. 2014 (ref. 25 in the main text) phylogeny as a backbone.

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Church, S.H., Donoughe, S., de Medeiros, B.A.S. et al. Insect egg size and shape evolve with ecology but not developmental rate. Nature 571, 58–62 (2019).

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