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Credits:

Dr. Peggy Rismiller, University of Adelaide
Mike McKelvey, Pelican Lagoon Research and Wildlife Centre
Dr. Stewart Nicol, University of Tasmania
Dr. Steve Johnston, University of Queensland
Dr. Jane C. Fenelon, University of Melbourne
Dr. Kate DuttonRegester, University of Queensland
Dr. Ingmar Werneburg, Senckenberg Research Institute
Dr. Marcelo SánchezVillagra, University of Zurich
Taronga Zoo Sydney
San Diego Zoo Wildlife Alliance
RISMAC

Steve Gartner “The echidna (or spiny anteater) (1969)”
© Copyright CSIRO AustraliaThe echidna (or spiny anteater) (1969)
https://csiropedia.csiro.au/echidnas...

© Copyright CSIRO AustraliaComparative biology of lactation (1974)
   • Echidna hatching (1974)  

BBC Natural History / Getty Images

Citations

Alibardi L, Rogers G. Observations on fur development in echidna (Monotremata, Mammalia) indicate that spines precede hairs in ontogeny. Anat Rec (Hoboken). 2015 Apr;298(4):76170. doi: 10.1002/ar.23081. Epub 2014 Nov 13. PMID: 25367156.

DuttonRegester, KJ. New insights into the reproductive physiology of female shortbeaked echidnas. The University of Queensland (2022). https://doi.org/10.14264/1f48195

DuttonRegester KJ, Roser A, Meer H, Renfree MB, Phillips C, Johnston SD. Reproductive behaviour before and after oestrus and oviposition in the captive shortbeaked echidna (Tachyglossus aculeatus). Reprod Fertil Dev. 2022 Sep;34(14):920932. doi: 10.1071/RD22092.

Fahmy, M.A.B. (2020). Aposthia. In: Normal and Abnormal Prepuce. Springer, Cham. https://doi.org/10.1007/9783030376...

Fenelon JC, Bennetts A, Anthwal N, Pyne M, Johnston SD, Evans AR, Tucker AS, Renfree MB. Getting out of a mammalian egg: the egg tooth and caruncle of the echidna. Dev Biol. 2023 Mar;495:818. doi: 10.1016/j.ydbio.2022.12.005.

Fenelon, Jane C., Caleb McElrea, Geoff Shaw, Alistair R. Evans, Michael Pyne, Stephen D. Johnston, Marilyn B. Renfree; The Unique Penile Morphology of the ShortBeaked Echidna, Tachyglossus aculeatus. Sex Dev 20 September 2021; 15 (4): 262–271. https://doi.org/10.1159/000515145

Grützner, Frank & Nixon, Brett & Jones, Russell. (2008). Reproductive Biology in EggLaying Mammals. Sexual development : genetics, molecular biology, evolution, endocrinology, embryology, and pathology of sex determination and differentiation. 2. 11527. 10.1159/000143429.

Johnston SD, Smith B, Pyne M, Stenzel D, Holt WV. Onesided ejaculation of echidna sperm bundles. Am Nat. 2007 Dec;170(6):E1624. doi: 10.1086/522847.

Nicol, Stewart C., Andersen Niels A., Morrow Gemma E., Harris Rachel L. (2019) Spurs, sexual dimorphism and reproductive maturity in Tasmanian echidnas (Tachyglossus aculeatus setosus). Australian Mammalogy 41, 161169. https://doi.org/10.1071/AM18005

Nixon B, Ecroyd HW, Dacheux JL, Jones RC. Monotremes provide a key to understanding the evolutionary significance of epididymal sperm maturation. J Androl. 2011 NovDec;32(6):66571. doi: 10.2164/jandrol.110.012716.

Rismiller, Peggy D & Frank Grutzner, Tachyglossus aculeatus (Monotremata: Tachyglossidae), Mammalian Species, Volume 51, Issue 980, 3 October 2019, Pages 75–91, https://doi.org/10.1093/mspecies/sez012

Rismiller PD, McKelvey MW. Body mass, age and sexual maturity in shortbeaked echidnas, Tachyglossus aculeatus. Comp Biochem Physiol A Mol Integr Physiol. 2003 Dec;136(4):85165. doi: 10.1016/s10956433(03)002253.

Werneburg, Ingmar & SánchezVillagra, Marcelo. (2011). The early development of the echidna, Tachyglossus aculeatus (Mammalia: Monotremata), and patterns of mammalian development. Acta Zool.. 82. 10.5167/uzh32695.

Wheelhouse, Jaimee, Larry Vogelnest, Robert G Nicoll, Skeletal radiographic anatomy of echidnas: insights into unusual mammals, Journal of Mammalogy, Volume 103, Issue 4, August 2022, Pages 920–931, https://doi.org/10.1093/jmammal/gyab138