When the value of d is small (d ≤ 0.02), the characteristic value of Δ for which the advantage of producing P diminishes is smaller than that for which the advantage of producing M diminishes (compare Figs. 4 and 7).
I had already mentioned that expansion of the digestion chamber volume and distancing the active centre from the exterior to reduce random digestion of the wrong substrate is a plausible selective advantage for the transition from HslV to proteasome rather than the reverse for which no advantage is obvious, and which is likely to be harmful.
When the value of d is great (e.g. d = 0.05), the value of Δ for which the advantage of producing P critically diminishes is about the same as that for the advantage of producing M. Thus, the evolved value of r ¯ monotonically decreases to 1/2 as Δ increases.
To summarize the essence of the above results, the advantage of producing M diminishes as the diffusion intensity increases, and the characteristic point for which this advantage critically diminishes is when Δ and the effective rate of replication [ a in Eqs. (8) and (9)] are of the same order of magnitude (Fig. 4).
The advantage of producing P also diminishes as Δ increases; however, the characteristic value of Δ for which the advantage of producing P diminishes now depends more strongly on the decay rate (d), because it depends on the mean square displacement of – i.e. distance traveled by – a molecule in its average life time, which is proportional to Δ / d.
Only the existence of a second threshold, for which the advantage of resistance is restored at high transmission intensity, is dependent in our theoretical results on the assumption that the duration of infection increases as individuals acquire higher levels of immunity.
iRBC cytoadhesion causes other endothelial cell changes, for which the advantage to the parasite is less clear, but which are nonetheless implicated in pathogenesis.
The potential for such clonal expansion has recently been described even in the context of a disorder for which no known advantage for genetically corrected cells exists.
In the present study, weight gain from weaning to yearling was the only trait for which a clear advantage in terms of empirical accuracy was observed for GBLUP.
Only mutations for which the survival advantage in sheep was precisely balanced by their detrimental pleiotropic effects remained segregating in the long term.
