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Type: Article
Published: 2022-04-05
Page range: 471-482
Abstract views: 612
PDF downloaded: 40

GroupStruct: An R Package for Allometric Size Correction

Lee Kong Chian Natural History Museum, 2 Conservatory Drive, 117377 Singapore.
Herpetology Laboratory, Department of Biology, La Sierra University, 4500 Riverwalk Parkway, Riverside, California 92505, USA.
General Allometry GroupStruct Morphology Ontogenetic variation Principal components analysis Size correction


The efficacy of an allometric growth model to correct for ontogenetic body size variation has been known for decades, yet this method remains relatively obscure and rarely applied. We optimize the implementation of this method through a newly developed and easy-to-use R package GroupStruct and further extend its application from intraspecific to interspecific datasets. Using empirical examples, we show that different size correction methods (i.e., ratios, residuals, and allometry) can result in vastly different conclusions. Our results demonstrate that choosing the appropriate size correction method is crucial as it can have significant impacts on downstream analyses and has the potential to alter biological interpretations.



  1. Albrecht, G.H., Gelvin, B.R. & Hartman, S.E. (1993) Ratios as a size adjustment in morphometrics. American Journal of Physical Anthropology, 91, 441–468.
    Berner, D. (2011) Size correction in biology: How reliable are approaches based on (common) principal component analysis? Oecologia, 166, 961–971.
    Blackburn, D.C., Siler, C.D., Diesmos, A.C., Mcguire, J.A., Cannatella, D.C. & Brown, R.M. (2013) An adaptive radiation of frogs in a southeast asian island archipelago. Evolution, 67, 2631–2646.
    Bolker, B., Holyoak, M., Krivan, V., Rowe, L. & Schmitz, O.J. (2003) Connecting theoretical and empirical studies of trait-mediated interactions. Ecology, 84, 1101–1114.[1101:CTAESO]2.0.CO;2
    Bretz, F., Hothorn, T. & Westfall, P. (2010) Multiple Comparisons Using R. Chapman and Hall/CRC, London, 208 pp.
    Calderón-Espinosa, M.L., Ortega-León, A.M. & Zamora-Abrego, J.G. (2013) Intraspecific variation in body size and shape in an Andean highland anole species, Anolis ventrimaculatus (Squamata: Dactyloidae). Revista de Biologia Tropical, 61, 255–262.
    Chan, K.O., Abraham, R.K., Grismer, J.L. & Grismer, L.L. (2018) Elevational size variation and two new species of torrent frogs from Peninsular Malaysia (Anura: Ranidae: Amolops Cope). Zootaxa, 4434 (2), 250–264.
    Chan, K.O., Alexander, A.M., Grismer, L.L., Su, Y.-C., Grismer, J.L., Quah, E.S.H. & Brown, R.M. (2017) Species delimitation with gene flow: a methodological comparison and population genomics approach to elucidate cryptic species boundaries in Malaysian Torrent Frogs. Molecular Ecology, 26, 5435–5450.
    Chan, K.O., Grismer, L.L. & Brown, R.M. (2014) Reappraisal of the Javanese Bullfrog complex, Kaloula baleata (Müller, 1836) (Amphibia: Anura: Microhylidae), reveals a new species from Peninsular Malaysia. Zootaxa, 3900 (4), 569–580.
    Chole, H., Woodard, S.H. & Bloch, G. (2019) Body size variation in bees: regulation, mechanisms, and relationship to social organization. Current Opinion in Insect Science, 35, 77–87.
    Freckleton, R.P. (2002) On the misuse of residuals in ecology: regression of residuals vs . multiple regression. Journal of Animal Ecology, 71, 542–545.
    Garcia-Berthou, E. (2001) On the misuse of residuals in ecology: testing regression residual vs. the analysis of covariance. Journal of Animal Ecology, 70, 708–711.
    Gaskins, C.T. & Anderson, D. (1976) Statistical properties of ratios. i. empirical results. Systematic Zoology, 25, 137–148.
    Green, A.J. (2016) Mass/length residuals: Measures of body condition or generators of spurious results? Ecology, 82, 1473–1483.[1473:MLRMOB]2.0.CO;2
    Grismer, L.L. & Grismer, J.L. (2017) A re-evaluation of the phylogenetic relationships of the Cyrtodactylus condorensis group (Squamata; Gekkonidae) and a suggested protocol for the characterization of rock-dwelling ecomorphology in Cyrtodactylus. Zootaxa, 4300 (4), 486–504.
    Grismer, L.L., Rujirawan, A., Termprayoon, K., Ampai, N., Yodthong, S., Wood, P.L.J., Oaks, J.R. & Aowphol, A. (2020a) A new species of Cyrtodactylus Gray (Squamata; Gekkonidae) from the Thai Highlands with a discussion on the evolution of habitat preference. Zootaxa, 4852 (4), 401–427.
    Grismer, L.L., Wood. P.L.J., Thura, M.K., Quah, E.S.H., Murdoch, M.L., Grismer, M.S., Herr, M.W., Lin, A. & Kyaw, H. (2018a) Three more new species of Cyrtodactylus (Squamata: Gekkonidae) from the Salween Basin of eastern Myanmar underscore the urgent need for the conservation of karst habitats. Journal of Natural History, 52, 1243–1294.
    Grismer, L.L., Wood, P.L.J., Grismer, M.S., Quah, E.S.H., Kyaw, M. & Oaks, J.R. (2020b) Integrative taxonomic and geographic variation analyses in Cyrtodactylus aequalis (Squamata: Gekkonida) from southern Myanmar (Burma): one species, two different stories. Israel Journal of Ecology & Evolution, 2020, 1–29.
    Grismer, L.L., Wood, P.L.J., Kyaw Thura, M., Thaw, Z.I.N., Quah, E.S.H., Murdoch, M.L., Grismer, M.S., Aung, L.I.N., Kyaw, H. & Lwin, N. (2018b) Twelve new species of Cyrtodactylus Gray (Squamata: Gekkonidae) from isolated limestone habitats in east-central and southern Myanmar demonstrate high localized diversity and unprecedented microendemism. Zoological Journal of the Linnean Society, 182, 862–959.
    Grismer, L.L., Wood, P.L.J., Quah, E.S.H., Grismer, M.S., Thura, M.K., Oaks, J.R. & Lin, A. (2020c) Two new species of Cyrtodactylus Gray, 1827 (Squamata: Gekkonidae) from a karstic archipelago in the Salween Basin of southern Myanmar (Burma). Zootaxa, 4718 (2), 151–183. /10.11646/zootaxa.4718.2.1
    Klingenberg, C. (1996) Multivariate Allometry. In: Marcus, L.F., Corti, M., Loy, A., Naylor, G.J.P. & Slice, D.E. (Eds.), Advances in Morphometrics. Springer, Boston, Massachusetts, pp. 23–49.
    Klingenberg, C.P. (1998) Heterochrony and allometry: The analysis of evolutionary change in ontogeny. Biological Reviews, 73, 79–123.
    Klingenberg, C.P. (2016) Size, shape, and form: concepts of allometry in geometric morphometrics. Development Genes and Evolution, 226, 113–137.
    Krohne, D.T. (2015) Ecology: Evolution, Application, Integration. Oxford University Press, Oxford, 552 pp.
    Lleonart, J., Salat, J. & Torres, G.J. (2000) Removing allometric effects of body size in morphological analysis. Journal of Theoretical Biology, 205, 85–93.
    Mahler, D.L., Revell, L.J., Glor, R.E. & Losos, J.B. (2010) Ecological opportunity and the rate of morphological evolution in the diversification of greater Antillean anoles. Evolution, 64, 2731–2745.
    McCoy, M.W., Bolker, B.M., Osenberg, C.W., Miner, B.G. & Vonesh, J.R. (2006) Size correction: Comparing morphological traits among populations and environments. Oecologia, 148, 547–554.
    Nakagawa, S., Kar, F., Dea, R.E.O., Pick, J.L. & Lagisz, M. (2017) Divide and conquer? Size adjustment with allometry and intermediate outcomes. BMC Evolutionary Biology, 15, 107.
    Parins-Fukuchi, C. (2018) Use of continuous traits can improve morphological phylogenetics. Systematic Biology, 67, 328–339.
    R Core Team (2014) A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna. [program]
    Reist, J.D. (1985) An empirical evaluation of several univariate methods that adjust for size variation in morphometric data. Canadian Journal of Zoology, 63, 1429–1439.
    Revell, L.J. (2009) Size-correction and principal components for interspecific comparative studies. Evolution, 63, 3258–3268.
    Rogell, B., Dowling, D.K. & Husby, A. (2020) Controlling for body size leads to inferential biases in the biological sciences. Evolution Letters, 4, 73–82.
    Stillwell, R.C., Morse, G.E. & Fox, C.W. (2007) Geographic variation in body size and sexual size dimorphism of a seed-feeding beetle. American Naturalist, 170, 358–369.
    Thorpe, R.S. (1975) Quantitative handling of characters useful in snake systematics with particular reference to intraspecific variation in the Ringed Snake Natrix natrix. Biological Journal of the Linnean Society, 7, 27–43.
    Thorpe, R.S. (1976) Biometric analysis of geographic variation and racial affinities. Biological Reviews, 51, 407–452
    Thorpe, R.S. (1983) A review of the numerical methods for recognising and analysing racial differentiation. In: Felsenstein, J. (Eds.), Numerical Taxonomy. Springer Verlag, Berlin and Heidelberg, pp. 404–423.
    Werner, E.E. & Peacor, S.D. (2003) A review of trait-mediated indirect interactions in ecological communities. Ecology, 84, 1083–1100.[1083:AROTII]2.0.CO;2