The energetics of incubating an egg

Hermann Rahn and Charles Paganelli

Hermann Rahn (l) and Charles Paganelly (r), the two pioneers of the physiology of birds' eggs. I spent a two year post-doctoral stint the Hermann and Charles in the mid 1980s.

The energy costs of incubation were my main research interest from the end of graduate school through my first few years on the faculty of SUNY-ESF

My interests were driven by some dissatisfaction with the way this concept had made its way into the ecological literature. If one could estimate how much energy it cost a parent to keep its egg warm, the reasoning went, this could be used as a predictive tool in exploring broader questions, such as timing of incubation bouts, structure of nests, and clutch size and frequency.

That's sound as far as it goes. The trouble was that the biophysical models that ecologists were using were based upon erroneous assumptions about how heat moved in eggs, what capacity the embryo had in manipulating this, how heat moved into an egg from an incubating bird's brood patch, and how best to estimate the effects of intermittent application of heat from the parent. These errors were leading ecologists to make predictions about incubation energetics that were wildly in error.

My motivation in this research was to try and put these ideas onto a sound theoretical and emprical footing.

Selected publications

Turner, J. S. (2002). Maintenance of egg temperature. Avian Incubation: Behaviour, Environment and Evolution. D. C. Deeming. Oxford, Oxford University Press: 118-142.

Turner, J. S. (1991). The thermal energetics of incubated birds' eggs. Egg Incubation: Its Effects on Embryonic Development in Birds and Reptiles. D. C. Deeming and M. W. J. Ferguson. Cambridge, Cambridge University Press: 117-145.

Incubation links



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