This April 16, 2005 post gives you links to further online resources and literature on entrainment and Phase-Response Curves, as well as a link to a database of PRCs so you can play with them yourself.
One of the most useful chronobiological databases available online is the PRC Atlas. Compiled by Dr.Carl Johnson of Vanderbilt University, it contains hundreds of published and unpublished Phase-Response Curves. One can sort the Curves by species or by type of stimulus (e.g., light pulses, pulses of varius chemicals, dark pulses on constant-light background, etc.) and one is also able to manipulate (i.e., re-plot) the data to one's own liking.
The page contains links to four important papers/reviews of the utlility of PRC-construction in studies of circadian rhythms as well as a list of further references. The files are available for PC and Mac and one can use them even on very old operating systems as the files were prepared more than a decade ago.
There is also a useful little page of comments on the way PRCs are plotted in the Atlas and are usually plotted (or should be plotted) in the literature.
Unfortunately, the database has not been updated for at least the past 6-7 years, so some more recent PRCs are not included. Still, if one is interested in performing a meta-analysis (e.g., correlating particular circadian properties with ecological niches or phylogenetic histories - I wish someone would actually do this), the data are freely available on this website.
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