Pamela Moresby wrote:What are the optimum temperatures for caterpillars.
Chip discussed the concept of "developmental zero" in the "Teaching with Monarchs" article in the January 2005 Newsletter:
http://www.monarchwatch.org/update/2005 ... ching.html
Generally speaking, you can speed development of monarch eggs, larvae and pupae by increasing the rearing temperature; however, as you implied there is certainly an upper limit. Sustained temperatures of about 91.4F (33C) will inhibit development and lead to mortality. It has been shown that monarch metabolic rate and growth peaks at 84.2F (29C) (Zalucki 1982), so this could be considered the optimum rearing temperature for monarchs.