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Australian Mammalogy Australian Mammalogy Society
Journal of the Australian Mammal Society
RESEARCH ARTICLE

The marsupial nasal system: a review of its structure, function, and evolutionary significance, with a focus on wombats

Julie M. Old https://orcid.org/0000-0002-2754-7757 A * , Amelia M. Dege A , Niamh Le Breton A , Kaya H. Sheehan A and Layla Yaghi A
+ Author Affiliations
- Author Affiliations

A School of Science, Hawkesbury, Western Sydney University, Penrith, NSW 2751, Australia.

* Correspondence to: j.old@westernsydney.edu.au

Handling Editor: Bronwyn McAllan

Australian Mammalogy 47, AM25023 https://doi.org/10.1071/AM25023
Submitted: 16 June 2025  Accepted: 31 August 2025  Published: 19 September 2025

© 2025 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the Australian Mammal Society.

Abstract

The nose or snout is an important anatomical structure of mammals. It is responsible for inspiration and expiration of gases into the lungs, temperature regulation and olfaction, and it is also essential for supporting navigation, foraging and immunological defence in animals. Snouts are also often used to differentiate and classify mammals. This review investigates the critical role of the snout and its accessory structures, and how it supports mammalian survival. We use wombats as a specific example, given their iconic status and that extant species are classified based on the appearance of their rhinarium, to identify gaps in our knowledge of the marsupial snout and its function.

Keywords: behaviour, communication, mammal, marsupial, mucosal-associated lymphoid tissue, olfaction, vomeronasal organ, whiskers.

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