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 April 17, 2009
Journal of Experimental Biology 212, 1302-1306 (2009)
Published by The Company of Biologists 2009
doi: 10.1242/jeb.027425
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 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 Du, W.-G.
Right arrow Articles by Shine, R.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Du, W.-G.
Right arrow Articles by Shine, R.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

Determinants of incubation period: do reptilian embryos hatch after a fixed total number of heart beats?

Wei-Guo Du1,2,*, Rajkumar S. Radder1,{dagger}, Bo Sun2 and Richard Shine1

1 School of Biological Sciences A08, University of Sydney, NSW, 2006 Australia
2 Hangzhou Key Laboratory for Animal Science and Technology, College of Biological and Environmental Sciences, Hangzhou Normal University, 310036, Hangzhou, People's Republic of China


Figure 1
View larger version (19K):
[in this window]
[in a new window]

  		Fig. 1. Effects of mean incubation temperature on (A) heart beat rates (beats min–1), (B) total duration of incubation and (C) developmental rates of the turtle Pelodiscus sinensis and the lizards Takydromus septentrionalis and Bassiana duperreyi. (A) Heart beat rates were measured by non-invasive methods and are expressed as means ± s.e.m. (B) Mean incubation durations were collected from published reports on B. duperreyi (Shine and Harlow, 1996Go), T. septentrionalis (Du, 2003Go) and P. sinensis (Du and Ji, 2003Go; Ji et al., 2003Go). (C) Developmental rate at each temperature was calculated by dividing incubation duration by the shortest incubation duration recorded in the laboratory and taking the inverse of this value. Data on T. septentrionalis and P. sinensis were taken from Du (Du, 2003Go) and Du and Ji (Du and Ji, 2003Go), respectively. Data on B. duperreyi were taken from Shine and Harlow (Shine and Harlow, 1996Go). HR, heart rate; T, temperature; DR, developmental rate.

 

Figure 2
View larger version (14K):
[in this window]
[in a new window]

  		Fig. 2. Thermal dependence of the total number of heart beats prior to hatching and the total number of effective heart beats (i.e. excluding those that occur at temperatures too low for embryonic growth and differentiation) in the non-avian reptiles Pelodiscus sinensis, Takydromus septentrionalis and Bassiana duperreyi. Total heart beats over the course of incubation increased at lower temperatures whereas the total number of effective heart beats did not differ significantly among temperatures. Data are expressed as means ± s.e.m. Means with different letters above their error bars are statistically different (Tukey's post-hoc test).

 

Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?



© The Company of Biologists Ltd 2009