CSIRO Publishing blank image blank image blank image blank imageBooksblank image blank image blank image blank imageJournalsblank image blank image blank image blank imageAbout Usblank image blank image blank image blank imageShopping Cartblank image blank image blank image You are here: Journals > Australian Journal of Zoology   
Australian Journal of Zoology
Journal Banner
  Evolutionary, Molecular and Comparative Zoology
 
blank image Search
 
blank image blank image
blank image
 
  Advanced Search
   

Journal Home
About the Journal
Editorial Board
Contacts
Content
Online Early
Current Issue
Just Accepted
All Issues
Special Issues
Sample Issue
For Authors
General Information
Notice to Authors
Submit Article
Open Access
For Referees
Referee Guidelines
Review an Article
Annual Referee Index
For Subscribers
Subscription Prices
Customer Service
Print Publication Dates

blue arrow e-Alerts
blank image
Subscribe to our Email Alert or RSS feeds for the latest journal papers.

red arrow Connect with us
blank image
facebook twitter youtube

red arrow Supplementary Series
blank image
All volumes of the Australian Journal of Zoology Supplementary Series are online and available to subscribers of Australian Journal of Zoology.

 

Article << Previous     |     Next >>   Contents Vol 36(5)

Circumventing a Constraint - the Case of Thylacoleo (Marsupialia, Thylacoleonidae)

L Werdelin

Australian Journal of Zoology 36(5) 565 - 571
Published: 1988

Abstract

Marsupial carnivores of the order Dasyurida are more uniform in molar morphology and jaw geometry than are their placental counterparts. This difference is related to the difference in tooth replacement between marsupials and placentals. In Carnivora, the permanent carnassial can erupt in its (geometrically) permanent position, and the post-carnassial teeth are free to evolve in various ways. In the Dasyurida, each erupting molar in turn functions as carnassial before being pushed forwards (relatively) in the jaw by the next erupting molar, which in turn becomes the carnassial. Thus, in the Dasyurida, all molars come to have carnassiform morphology. One group of Australian fossil carnivores has avoided this constraint: the Thylacoleonidae, 'marsupial lions'. In this group, P3/3 are the teeth functioning as carnassials, having been coopted for this function from the presumed sectorial P3/3 of the herbivorous ancestors of Thylacoleonidae. This has made molar reduction possible in this group, but has brought about some incidental effects. P3/3 lie far forward in the jaw, and the muscle resultant has been shifted forwards to compensate for this, reducing gape, but increasing bite force at I1/1, teeth which function as canines in Thylacoleonidae.



Full text doi:10.1071/ZO9880565

© CSIRO 1988

blank image
Subscriber Login
Username:
Password:  

 
PDF (344 KB) $25
 Export Citation
 Print
  
    
Legal & Privacy | Contact Us | Help

CSIRO

© CSIRO 1996-2014