Journal of Zoology



Respiratory turbinates of canids and felids: a quantitative comparison


Blaire Van Valkenburgh a1c1, Jessica Theodor a2, Anthony Friscia a1, Ari Pollack a1 and Timothy Rowe a3
a1 Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095-1606, U.S.A.
a2 Department of Geology, Illinois State Museum, 1011 East Ash Street, Springfield, IL 62703, U.S.A.
a3 Department of Geological Sciences, University of Texas, Austin, TX 78712, U.S.A.

Article author query
van valkenburgh b   [PubMed][Google Scholar] 
theodor j   [PubMed][Google Scholar] 
friscia a   [PubMed][Google Scholar] 
pollack a   [PubMed][Google Scholar] 
rowe t   [PubMed][Google Scholar] 

Abstract

The respiratory turbinates of mammals are complex bony plates within the nasal chamber that are covered with moist epithelium and provide an extensive surface area for the exchange of heat and water. Given their functional importance, maxilloturbinate size and structure are expected to vary predictably among species adapted to different environments. Here the first quantitative analysis is provided of maxilloturbinate structure based on high-resolution computed tomography (CT) scans of the skulls of eight canid and seven felid species. The key parameters examined were the density of the maxilloturbinate bones within the nasal chamber and how that density varied along the air pathway. In both canids and felids, total maxilloturbinate chamber volume and bone volume increased with body size, with canids having c. 1.5–2.0 times the volume of maxilloturbinate than felids of similar size. In all species, the volume of the maxilloturbinates varies from rostral to caudal, with the peak volume occurring approximately midway, close to where airway cross-sectional area is greatest. Interspecific differences among canids or felids in maxilloturbinate density were not consistent with adaptive explanations, i.e. the densest maxilloturbinates were not associated with species living in arid or cold habitats. Some of the observed variation in maxilloturbinate form might reflect a need for both low- and high-resistance pathways for airflow under alternative conditions.

(Accepted March 31 2004)


Key Words: carnivorans; turbinates; respiration; nasal anatomy.

Correspondence:
c1 All correspondence to: B. Van Valkenburg. E-mail: bvanval@ucla.edu