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SCIENCE

The Claim

Male antechinuses usually live for only one breeding season.

The Short Version

Male Antechinus are well documented as breeding once and then dying soon after, with post-mating male mortality typically near 100%. Peer-reviewed studies across the genus describe this as semelparity or effectively suicidal reproduction. The wording “usually” is therefore accurate, and if anything slightly cautious.

Caveats

  • Mortality rates can vary somewhat by species and population, but the core pattern remains a single breeding season for males.
  • “Usually” slightly softens the biology: in many Antechinus species, male die-off after mating is so extreme that survival to a second season is virtually absent.
  • Popular articles often use dramatic phrasing such as “sex until they die”; the reliable basis is the peer-reviewed literature on post-mating mortality and semelparity.

The Receipts

  1. Live fast, die young, and win the sperm competition

    Proceedings of the National Academy of Sciences (PNAS)

  2. Sperm competition drives the evolution of suicidal reproduction in mammals

    Proceedings of the National Academy of Sciences (via PubMed Central)

  3. Extreme sleep loss in a semelparous marsupial

    Current Biology (Cell Press)

  4. A chromosome‐level genome of Antechinus flavipes provides a resource for investigating the evolution of semelparity and age‐related neuropathologies in mammals

    PubMed Central (Evolutionary Applications)

  5. Postmating Mortality of Males in the Dasyurid Marsupials, Dasyurus and Parantechinus

    Journal of Mammalogy / JSTOR

  6. Semelparous marsupials reduce sleep for sex

    Current Biology (Cell Press)

  7. Extreme semelparity and egg retention in the Australian marsupial genus Antechinus

    Biological Journal of the Linnean Society (Oxford Academic)

  8. Obligate male semelparity in dasyurid marsupials

    Journal of Mammalogy

  9. Semelparity and the evolution of suicidal reproduction in dasyurid marsupials

    Science

  10. Reproduction and survival in Antechinus stuartii

    Wildlife Research (CSIRO Publishing)

+ 15 more sources — see the full list on Lenz

Filed Under

Antechinus

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