Encyclopedia of Animal Cognition and Behavior

Living Edition
| Editors: Jennifer Vonk, Todd Shackelford

Monotreme Sensory Systems

  • Ken W. S. AshwellEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-47829-6_2066-1



Monotremes are a unique group of mammals confined to Australia and New Guinea. The lineage leading to modern monotremes probably diverged from that leading to therians (modern placental and marsupial mammals) as much as 220 million years ago (Yu et al. 2012), so there has been abundant time for independent evolution of sensory systems and the brain. Modern monotremes cannot be considered primitive or relict, and they are certainly not models for the ancestors of placental mammals. Monotremes have undergone just as long a period of evolution as have therians. Furthermore, although they do exhibit some primitive characteristics, living monotremes are also highly specialized animals with some remarkably advanced neural adaptations (e.g., electroreception and isocortical expansion). Like all mammals (including humans), they are therefore the result of mosaic evolution, where primitive and derived...

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  1. Aitkin, L. M., & Johnstone, B. M. (1972). Middle ear function in a monotreme: The echidna (Tachyglossus aculeatus). Journal of Experimental Zoology, 180, 245–250.CrossRefGoogle Scholar
  2. Andres, K. H., & von Düring, M. (1988). Comparative anatomy of vertebrate electroreceptors. Progress in Brain Research, 74, 113–131.CrossRefGoogle Scholar
  3. Andres, K. H., von Düring, M., Iggo, A., & Proske, U. (1991). The anatomy and fine–structure of the echidna Tachyglossus aculeatus snout with respect to its different trigeminal sensory receptors including the electroreceptors. Anatomy and Embryology, 184, 371–393.CrossRefGoogle Scholar
  4. Ashwell, K. W. S. (2006). Chemoarchitecture of the monotreme olfactory bulb. Brain, Behavior and Evolution, 67, 69–84.CrossRefGoogle Scholar
  5. Ashwell, K. W. S., & Phillips, J. M. (2006). The anterior olfactory nucleus and piriform cortex of the echidna and platypus. Brain, Behavior and Evolution, 67, 203–227.CrossRefGoogle Scholar
  6. Butler, A. B., & Hodos, W. (2005). Comparative vertebrate neuroanatomy. Evolution and adaptation (2nd ed.). Hoboken: Wiley.CrossRefGoogle Scholar
  7. Campbell, C. B. G., & Hayhow, W. R. (1971). Primary optic pathways in echidna, Tachyglossus aculeatus – Experimental degeneration study. Journal of Comparative Neurology, 143, 119–136.CrossRefGoogle Scholar
  8. Campbell, C. B. G., & Hayhow, W. R. (1972). Primary optic pathways in the duckbill platypus, Ornithorhynchus anatinus: An experimental degeneration study. Journal of Comparative Neurology, 145, 195–208.CrossRefGoogle Scholar
  9. Divac, I., Holst, M.–. C., Nelson, J., & McKenzie, J. S. (1987). Afferents of the frontal cortex in the echidna (Tachyglossus aculeatus). Indication of an outstandingly large prefrontal cortex. Brain, Behavior and Evolution, 30, 303–320.CrossRefGoogle Scholar
  10. Fox, R. C., & Meng, J. (1997). An x-radiographic and SEM study of the osseous inner ear of multituberculates and monotremes (Mammalia): Implications for mammalian phylogeny and evolution of hearing. Zoological Journal of the Linnean Society, 121, 249–291.CrossRefGoogle Scholar
  11. Gates, G. R. (1978). Vision in the monotreme echidna. In M. L. Augee (Ed.), Monotreme biology: The Australian Zoologist special symposium. Published in Australian Zoologist, 20, 147–169.Google Scholar
  12. Gray, A. A. (1908). An investigation on the anatomical structure and relationships of the labyrinth in the reptile, the bird and the mammal. Proceedings of the Royal Society of London, Series B: Biological Sciences, 80, 507–528.CrossRefGoogle Scholar
  13. Gregory, J. E., Iggo, A., McIntyre, A. K., & Proske, U. (1989). Responses of electroreceptors in the platypus bill to steady and alternating potentials. Journal of Physiology (London), 408, 391–404.CrossRefGoogle Scholar
  14. Griffiths, M. (1978). The biology of the Monotremes. New York: Academic.Google Scholar
  15. Grus, W. E., Shi, P., & Zhang, J. (2007). Largest vertebrate vomeronasal type 1 receptor gene repertoire in the semiaquatic platypus. Molecular Biology and Evolution, 24, 2153–2157.CrossRefGoogle Scholar
  16. Hunt, D. M., Carvalho, L. S., Cowing, J. A., Parry, J. W., Wilkie, S. E., Davies, W. L., & Bowmaker, J. K. (2007). Spectral tuning of shortwave-sensitive visual pigments in vertebrates. Photochemistry and Photobiology, 83, 303–310.CrossRefGoogle Scholar
  17. Iggo, A., Proske, U., McIntyre, A. K., & Gregory, J. E. (1988). Cutaneous electroreceptors in the platypus: A new mammalian receptor. Progress in Brain Research, 74, 133–138.CrossRefGoogle Scholar
  18. Krubitzer, L. (1998). What can monotremes tell us about brain evolution? Philosophical Transactions of the Royal Society. Series B, Biological Sciences, 353, 1127–1146.CrossRefGoogle Scholar
  19. Krubitzer, L., Manger, P., Pettigrew, J., & Calford, M. (1995). Organization of somatosensory cortex in monotremes. In search of the prototypical plan. Journal of Comparative Neurology, 351, 261–306.CrossRefGoogle Scholar
  20. Ladhams, A., & Pickles, J. O. (1996). Morphology of the monotreme organ of Corti and macula lagena. Journal of Comparative Neurology, 366, 335–347.CrossRefGoogle Scholar
  21. Manger, P. R., & Hughes, R. L. (1992). Ultrastructure and distribution of epidermal sensory receptors in the beak of the echidna, Tachyglossus aculeatus. Brain, Behavior and Evolution, 40, 287–296.CrossRefGoogle Scholar
  22. Manger, P. R., & Pettigrew, J. D. (1995). Electroreception and the feeding behaviour of platypus (Ornithorhynchus anatinus, Monotremata, Mammalia). Proceedings of the Royal Society of London, Series B: Biological Sciences, 347, 359–381.CrossRefGoogle Scholar
  23. Manger, P. R., & Pettigrew, J. D. (1996). Ultrastructure, number, distribution and innervation of electroreceptors and mechanoreceptors in the bill skin of the platypus, Ornithorhynchus anatinus. Brain, Behavior and Evolution, 48, 27–54.CrossRefGoogle Scholar
  24. Manger, P. R., Collins, R., & Pettigrew, J. D. (1997). Histological observations on presumed electroreceptors and mechanoreceptors in the beak skin of the long–beaked echidna. Zaglossus bruijnii. Proceedings of the Royal Society of London, Series B: Biological Sciences, 264, 165–172.CrossRefGoogle Scholar
  25. Nicol, S. C., Morrow, G. E., & Anderson, N. A. (2008). Hibernation in monotremes: a review. In B. G. Lovegrove & A. E. McKechnie (Eds.), Hypometabolism in animals: hibernation, torpor and cryobiology (pp. 251–262). Pietermaritzburg: University of KwaZulu-Natal.Google Scholar
  26. Niimura, Y., & Nei, M. (2007). Extensive gains and losses of olfactory receptor genes in mammalian evolution. PLoS One, 2, e708.CrossRefGoogle Scholar
  27. Pettigrew, J. D., Manger, P. R., & Fine, S. L. B. (1998). The sensory world of the platypus. Philosophical Transactions of the Royal Society. Series B, Biological Sciences, 353, 1199–1210.CrossRefGoogle Scholar
  28. Proske, U., Gregory, J. E., & Iggo, A. (1998). Sensory receptors in monotremes. Philosophical Transactions of the Royal Society. Series B, Biological Sciences, 353, 1187–1198.CrossRefGoogle Scholar
  29. Wakefield, M. J., Anderson, M., Chang, E., Wei, K. J., Kaul, R., Graves, J. A. M., Grützner, F., & Deeb, S. S. (2008). Cone visual pigments of monotremes: Filling the phylogenetic gap. Visual Neuroscience, 25, 257–264.CrossRefGoogle Scholar
  30. Yu, W., Xu, J., Wu, Y., & Yang, G. (2012). A comparative study of mammalian diversification pattern. International Journal of Biological Sciences, 8, 486–497.CrossRefGoogle Scholar
  31. Zeiss, C. J., Schwab, I. R., Murphy, C. J., & Dubietzig, R. W. (2011). Comparative retinal morphology of the platypus. Journal of Morphology, 272, 949–957.CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of Anatomy, School of Medical SciencesUniversity of New South WalesSydneyAustralia

Section editors and affiliations

  • Jennifer Vonk
    • 1
  1. 1.Oakland UniversityRochesterUSA