Skip to main content
Log in

Morphological analysis of threeInia (Cetacea: Iniidae) populations from Colombia and Bolivia

  • Published:
Acta Theriologica Aims and scope Submit manuscript

Abstract

We present new morphological data on three Colombian and BolivianInia populations. Analysis of morphometric data strongly suggests thatInia are sexually dimorphic, with males smaller for several variables and more heterogeneous than females. Our morphological data supported that Colombian Amazon males had the greatest total body length as well as greatest fluke values (tip to tip) compared to the males from the Orinoco and Bolivia Rivers. There were also significant differences in females among populations. The two Colombian groups (Amazon and Orinoco basin) presented greater total body length than the Bolivian array, while distance from jaw tip to tip of dorsal fin was greater in the Orinoco basin females than in the other two populations. A Canonic Population Analysis showed that the confidence intervals of the Colombian Amazon and Orinoco males were partially superposed. However, the Bolivian male sample was remarkably differing from these two populations. Two long standing debates exist in the systematic literature onInia: (1) the number of extant species (one,Inia geoffrensis, or twoI. geoffrensis andI. boliviensis) and (2) the number of extant subspecies ofI. geoffrensis (I. geoffrensis geoffrensis, I. geoffrensis humboldtiana andI. geoffrensis boliviensis). Using recent collections of both molecular and morphometric data, we suggest the existence of two distinct species ofInia with no subspecific distinction amongI. geoffrensis populations.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Anderson T. W. 1963. Asymptotic theory for principal component analysis. Annals of Mathematical Statistics 34: 122–148.

    Article  Google Scholar 

  • Banguera-Hinestroza E., Cardenas H., Ruiz-García M., Marmontel M., Gaitan E., Vazquez R. and Garcia--Vallejo F. 2002. Molecular Identification of Evolutionarily units in the Amazon River dolphin,Inia sp. (Cetacea: Iniidae). Journal of Heredity 93: 312–322.

    Article  CAS  PubMed  Google Scholar 

  • Bartlett M. S. 1950. Tests of significance in factor analysis. British Journal of Psychology 28: 97–104.

    Google Scholar 

  • Best R. C. and Da Silva V. M. F. 1983. Preliminary analysis of reproductive parameters of the boto,Inia geoffrensis, and the tucuxi,Sotalia fluviatilis, in the Amazon River system. 361-369. Reports of the International Whaling Commission, Special Issue 6: 1–495.

    Google Scholar 

  • Best R. C. and Da Silva V. M. F. 1989a. Biology, status and conservation ofInia geoffrensis in the Amazon and Orinoco river basin. [In: Biology and conservation of the river dolphins. W. F. Perrin, R. L. Brownell Jr, Zhou Kaiya, and Liu Jiankang, eds]. International Union for Conservation of Nature and Natural Resources (IUCN), Species Survival Commission, Occasional Paper 3: 23–24.

    Google Scholar 

  • Best R. C. and Da Silva V. M. F. 1989b. Amazon river dolphin, Boto.Inia geoffrensis (de Blainville, 1817). [In: Handbook of marine mammals. S. H. Ridgway and R. J. Harrison, eds]. Academic Press, London: 1–23.

    Google Scholar 

  • Best R. C. and Da Silva V. M. F. 1993.Inia geoffrensis. Mammalian Species 426: 1–8.

    Google Scholar 

  • Cadwell D. K. 1966. Morphological variation in the Amazon dolphin,Inia geoffrensis (Blainville). Year Book American Philosophy Society 328–331.

  • Casinos A. and Ocańa J. 1979. A craniometrical study of the genus Inia d’Orbigny, 1834 (Cetacea, Platanistoidea). Säugetierkundliche Mitteilungen 27: 194–206.

    Google Scholar 

  • Cuadras C. M. 1991. Métodos de An←isis Multivariante. Promociones y Publicaciones Universitarias. Barcelona: 1–644.

    Google Scholar 

  • Da Silva V. 1994. Aspects of the biology of the Amazonian dolphins genusInia andSotalia. PhD thesis, University of Cambridge: 1–329.

  • De Monte T., and Pilleri G. 1979. Cetacean haematology I. haemoglobin. Investigations on Cetacea 10: 277–287.

    Google Scholar 

  • Gower J. C. 1966. Some distance properties of latent root and vector methods used in multivariate analysis. Biometrika 53: 325–338.

    Google Scholar 

  • Grabert H. 1984. Migration and speciation of the South American Iniidae (Cetacea, Mammalia). Zeitschrift fur Säugetierkunde 49: 334–341.

    Google Scholar 

  • Harman H. H. 1976. Modern factor analysis. The University of Chicago Press, Chicago: 1–413.

    Google Scholar 

  • Hershkovitz P. 1966. Catalog of living whales. Bulletin of the United States Natural Museum 246: 1–259.

    Google Scholar 

  • Jolicoeur P. and Mosimann J. E. 1960. Size and shape variations in the painted turtle. A principal component analysis. Growth 24: 339–354.

    CAS  PubMed  Google Scholar 

  • Joliffe I. T. 1986. Principal component analysis. Springer-Verlag: New York: 1–296.

    Google Scholar 

  • Kaiser H. F. 1958. The varimax criterion for analytic rotation in factor analysis. Psichometrika 23: 187–200.

    Article  Google Scholar 

  • Layne J. N. 1956. Observations on freshwater dolphins in the Upper Amazon. Journal of Mammalogy 39: 1–22.

    Article  Google Scholar 

  • Mardia K. V., Kent J. T. and Birby J. M. 1979. Multivariate Analysis. Columbia Academic Press: 1–521.

  • Meade R. H., and Koehnken L. 1991. Distribution of the river dolphin, toninaInia geoffrensis, in the Orinoco river basin of Venezuela and Colombia. Interciencia 16: 300–312.

    Google Scholar 

  • Mohr E. 1964. Notizen uber den Flussdelphin bufeoInia geoffrensis (de Blainville, 1817). Zoologische Garten Jena 29: 262–270.

    Google Scholar 

  • Olivares A. 1962. Aves de la región Sur de la Sierra de la Macarena, Meta, Colombia. Revista de la Academia Colombiana de Ciencias 11: 306–344.

    Google Scholar 

  • Pilleri G. 1969. On the behaviour of the Amazon dolphinInia geoffrensis in Beni (Bolivia). Revue Suisse de Zoologie 76: 58–91.

    Google Scholar 

  • Pilleri G. 1972.Poppiana argent Inia nus Rathbun, 1909 (Crustacea, Decapoda) in the stomach contents ofInia geoffrensis from Rio Ibaré, Bolivia. Investigation on Cetacea 4: 104.

    Google Scholar 

  • Pilleri G. 1979. Observations on the ecology ofInia geoffrensis from the Rio Apure, Venezuela. Investigations on Cetacea 10: 136–142.

    Google Scholar 

  • Pilleri G., and Gihr M. 1969. Zur anatomie und pathologie vonInia geoffrensis de Blainville 1817 (Cetacea, Sussuidae) aus dem Beni, Bolivien. Investigations on Cetacea 1: 96–106.

    Google Scholar 

  • Pilleri G. and Gihr M. 1976. The manus of the Amazon dolphinInia geoffrensis (de Blainville, 1817) and remarks concerning so-called “polydactyly”. Investigations on Cetacea 7: 129–137.

    Google Scholar 

  • Pilleri G. and Gihr M. 1977. Observations on the Bolivian (Inia boliviensis d’Orbigny, 1834) and the Amazonian bufeo (Inia geoffrensis de Blainville, 1817) with a description of a new subspecies (Inia geoffrensis humboldtiana). Investigations on Cetacea 8: 11–76.

    Google Scholar 

  • Pilleri G. and Gihr M. 1981. Additional considerations on the taxonomy of the genusInia. Investigations on Cetacea 12: 15–27.

    Google Scholar 

  • Pilleri G., Marcuzzi G. and Pilleri O. 1982. Speciation in the Platanistoidea. Systematic, Zoogeographical and Ecological observations on recent species. Investigations on Cetacea 14: 15–46.

    Google Scholar 

  • Ruiz-García M. and Alvarez D. 1997. Significant evidences of spatial autocorrelation amongDrosophila pseudoobscura males and females from Colombia and USA populations using meristic morphological variables. Mendeliana 12: 63–89.

    Google Scholar 

  • Trebbau P. and Robineau D. 1974. Notes concerning the freshwater dolphin bufeoInia geoffrensis (de Blainville, 1817) in Venezuela. Zeitschrift für Säugertierkunde 39: 50–57.

    Google Scholar 

  • Van Bree P. J. H. and Robineau D. 1973. Notes sur les holotype de bufeoInia geoffrensis geoffrensis (de Blainville, 1817) et de bufeoInia geoffrensis boliviensis (d’Orbjgny, 1834) (Cetacea, Platinistidae). Mammalia 37: 658–664.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Additional information

Associate Editor was Joseph F. Merritt.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Ruiz-García, M., Banguera, E. & Cardenas, H. Morphological analysis of threeInia (Cetacea: Iniidae) populations from Colombia and Bolivia. Acta Theriol 51, 411–426 (2006). https://doi.org/10.1007/BF03195188

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF03195188

Key words

Navigation