Journal of Comparative Physiology B

, Volume 178, Issue 5, pp 545–562

Boom and bust: a review of the physiology of the marsupial genus Antechinus

Review

DOI: 10.1007/s00360-007-0250-8

Cite this article as:
Naylor, R., Richardson, S.J. & McAllan, B.M. J Comp Physiol B (2008) 178: 545. doi:10.1007/s00360-007-0250-8

Abstract

The marsupial genus Antechinus is a group of small carnivorous marsupials from the order Dasyuromorphia (Family Dasyuridae) and is found in eastern Australia. The life history of all species in the genus is characterized by a complex, but highly synchronized life cycle in both sexes, culminating in a short mating period followed by total male mortality (semelparity). The breeding season is defined by a specific rate of increase in photoperiod, which is different for each species. In Antechinus spp., male mortality is due to the effects of high free testosterone and cortisol levels on many organ systems. Unusually, spermatogenesis is complete before testosterone levels begin to rise at the winter solstice. In males, low sperm counts have been compensated for by high proportions of sperm reaching the isthmus of the female reproductive tract and long-term storage in the crypts. The females survive to rear their young and may mate again in their second year. Gestation lasts from 26 to 34 days, depending on the species. However, developmental arrest can occur at several stages during embryogenesis, elongating the apparent gestation duration by several days. Several species have strong female sex biases in their litters. The high degree of life history synchrony and the cascade of endocrine-driven physiological events that result in male death are unusual physiological characteristics for mammals. Suggestions why semelparity may have evolved in Antechinus are discussed.

Keywords

MarsupialRenal functionImmunosuppressionCortisolSemelparityTestosteroneAntechinus stuartiiAntechinus agilisReproductionSeasonality

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Department of PathologyBio21 Institute, The University of MelbourneParkvilleVictoriaAustralia
  2. 2.Department of Biochemistry and Molecular BiologyBio21 Institute, The University of MelbourneParkvilleAustralia
  3. 3.School of Medical SciencesRMIT UniversityBundooraAustralia
  4. 4.Physiology and Bosch Institute, School of Medical Sciences, Anderson Stuart Building, F13The University of SydneySydneyAustralia