A paper I never officially published
Make love and war – Quantifying discrete male polymorphic reproductive ratios
Fighters primarily develop at low population densities; Though the
proportion of males becoming fighters at any given density may change over time. This change is likely to be due to condition-dependence. Data is presented to illuminate these matters and a model is developed linking fighter development to the costs of being a fighter (in terms of survival) and the benefits of being a fighter (in terms of fecundity).