Fir waves, which occur only in E.N.America and Japan, provide a unique
opportunity to study the entire life cycle of a tree within a short period
of time. Among other uses, the system can be used to test life history
theory. Initially, we tested the idea that wave regeneration should select
for delayed reproduction or even semelparity in wave populations. Fieldwork
at Whiteface Mt. In upstate New York has shown this hypothesis to be wrong
and our subsequent work has been directed at discovering why. We will
present a graphical model of age/size-specific variation in the costs and
benefits of starting reproduction at any given time. This model can explain
the observed reproductive behaviour of firs in wave forests if the cost-
and benefit-curves have certain specific shapes. We report field-derived
estimates of these curves which support the model.
Silvertown, J. (1996). Are sub-alpine firs evolving towards semelparity? Evolutionary Ecology, 10, 77-80.
Silvertown, J. and Dodd, M. E. (1999). The demographic cost of reproduction and its consequences in balsam fir (Abies balsamea). American Naturalist, 154, 321-332.
Silvertown, J. and Dodd, M. E. (1999). Evolution of life history in balsam fir (Abies balsamea) in sub-alpine forests. Proceedings of the Royal Society of London B, 266, 729-733.
Dodd, M. E. and Silvertown, J. (2000). Size-specific fecundity and the influence of lifetime size variation upon effective population size in Abies balsamea. Heredity, 85, 604-609.