The natural selection of competitive interaction fix-points balance reproductive rates against mortality
The population dynamic feed-back of interactive competition is selecting a reproductive rate that is exactly so high that it produces an equilibrium abundance that generates the level of interference of the competitive interaction fix-point.
To deduce this we have e.g. the competitive interaction fix-point for a body mass in evolutionary equilibrium
ι** = 1 / ψ
This level of interference is also a function of the population density (
This equilibrium is defined also by density regulation, described for example by the discrete growth rate (λ) that is regulated from its maximum value of λm =
Lifetime reproduction is thus expected to be inversely related to the probability to survive to reproductive. And as this probability was predicted to be body mass invariant in the sections on inter-specific allometries, we expect a body mass invariant lifetime reproduction.
The probability to survive to reproduce is independent of body mass across 114 bird species (Fig. 1, left), and lifetime reproduction is body mass invariant across 221 species (middle).
And maximal yearly reproduction is inversely related to time-scaled survival (Ry ∝ 1/Tp) across 132 species of birds (Fig. 1, right), indicating a maximal lifetime reproduction that is inversely related to the probability to survive and reproduce [as RyT ∝ Rm ∝ 1/p].
There is also plenty of evidence that shows that populations with increased levels of anthropogenic or natural mortality evolve increased reproductive rates (e.g., Reznick and Bryga, 1987; Reznick et al., 1996; Broman, 2000; Sinclair et al., 2002; Coltman et al., 2003; Olsen et al., 2004; Edeline and Carlson, 2007).
Inevitable evolution: back to
Major life-history transitions by deterministic directional natural selection
A general theory of evolution. By means of selection by density dependent competitive interactions.
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