Long-term data sets that quantitatively confirm basic ecological theory are rare for field
populations. Highly variable recruitment often causes wide temporal variation in population
age distribution and basic theory for adaptive sex ratio often predicts ‘sex ratio tracking’ to
match the fluctuating age distribution. Using sex-changing shrimp as a model...
Recent comparative studies across sex-changing animals have found that the relative size and age at sex change are strikingly invariant. In particular, 91%–97% of the variation in size at sex change across species can be explained by the simple rule that individuals change sex when they reach 72% of their...
In a 1966 American Naturalist article, G. C. Williams
initiated the study of reproductive effort (RE) with the prediction
that longer-lived organisms ought to expend less in reproduction per
unit of time. We can multiply RE, often measured in fractions of
adult body mass committed to reproduction per unit time,...
Question: Are there general life-history rules for exploitation-caused extinction of mammal populations?
Mathematical methods: A population of size N faced with the added mortality of human exploitation will deterministically go extinct if its per-capita birth rate can no longer match its per-capita mortality rate as N approaches zero. We develop...