spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

First published online August 17, 2006
Journal of Experimental Biology 209, 3309-3321 (2006)
Published by The Company of Biologists 2006
doi: 10.1242/jeb.02393
This Article
Right arrow Summary Freely available
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Related articles in JEB
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Cartledge, V. A.
Right arrow Articles by Bradshaw, S. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Cartledge, V. A.
Right arrow Articles by Bradshaw, S. D.

Water balance of field-excavated aestivating Australian desert frogs, the cocoon-forming Neobatrachus aquilonius and the non-cocooning Notaden nichollsi (Amphibia: Myobatrachidae)

Victoria A. Cartledge1,*, Philip C. Withers1, Kellie A. McMaster1, Graham G. Thompson2 and S. Don Bradshaw1

1 Zoology, School of Animal Biology, MO92, University of Western Australia, Crawley, Western Australia 6009, Australia
2 Centre for Ecosystem Management, Edith Cowan University, 100 Joondalup Drive, Joondalup, Western Australia 6027, Australia


Figure 1
View larger version (15K):

[in a new window]
  		Fig. 1. Soil gravimetric water content (%) profiles of frog tunnels of (A) Notaden nichollsi in sand dunes in 2003 (squares) and 2004 (triangles); (B) cocooned Neobatrachus aquilonius in claypans in 2003 (squares) and 2004 (triangles); and (C) cocoonless N. aquilonius in a dune swale in 2004 (circles). Examples of individual burrow moisture profiles shown as grey lines.

 

Figure 2
View larger version (20K):

[in a new window]
  		Fig. 2. (A) Water retention curves for soil from Notaden nichollsi (dune and swale) and Neobatrachus aquilonius (claypan and swale) burrows. Each line represents a curve for a soil sample collected at a different excavation point within each site. (B) Relationship between soil gravimetric water content and water potential (Decagon Dewpoint PotentiaMeter) for dune, swale and claypan soil. Data are for soil samples taken at intervals from the soil surface down to the depth of the burrowed frog, during excavations in 2004. Grey symbols in B are beyond the resolution of the Decagon analyser and are between 0 and -100 kPa.

 

Figure 3
View larger version (84K):

[in a new window]
  		Fig. 3. (A) Electron micrograph of a transverse section through the cocoon of a Neobatrachus aquilonius excavated from a claypan in 2003. D, distal; P, proximal; NR, nuclear remnant. (B) Enlarged section of the box shown in A, showing individual cocoon layers. CL, cell layer composed of the remnants of dead epithelial cells; SCM, granular sub-corneal mucous layer; M, example of typical layer width measurement taken to include the cell layer and its underlying mucous layer; V, section through a cell vacuole; CJ, cell junction.

 

Figure 4
View larger version (19K):

[in a new window]
  		Fig. 4. Notaden nichollsi. (A) Total osmotic concentration of the plasma and urine of control (plasma N=7, urine N=5) and aestivating individuals excavated from sand dunes in 2003 (plasma N=7, urine N=8) and 2004 (plasma N=10, urine N=5). * indicates significant difference between plasma and urine osmolalities (one-tail t-test, P<0.05). (B) Relationship between plasma and urine osmolality for controls and frogs excavated from sand dunes in 2003 and 2004. The broken line represents isosmolality.

 

Figure 5
View larger version (21K):

[in a new window]
  		Fig. 5. Neobatrachus aquilonius. (A) Total osmotic concentration of the plasma and urine of control (plasma N=8, urine N=10) and cocooned aestivating frogs excavated from a claypan in 2003 (plasma N=6, urine N=5) and non-cocooned aestivating frogs from a dune swale in 2004 (plasma N=7, urine N=8). * indicates significant difference between plasma and urine osmolalities (one-tail t-test, P<0.05). (B) Relationship between plasma and urine osmolality for control and excavated cocooned frogs from a claypan in 2003 and excavated without cocoons from a swale in 2004. The broken line represents isosmolality.

 

Figure 6
View larger version (19K):

[in a new window]
  		Fig. 6. Relationship between plasma AVT concentration and plasma osmolality for control and field-excavated (A) Notaden nichollsi and (B) Neobatrachus aquilonius.

 




© The Company of Biologists Ltd 2006