Malthusian Relativityι**=7/3ψ
Life history evolution - traits & transitions

Reproductive rate

The reproduction of natural species is inversely related to mortality

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).

Fig. 1 The body mass (w) dependence for (left) the probability to survive to reproduce (p) and (middle) maximal lifetime reproduction (Rm) across 114 and 221 species of bird. For 132 bird species, the right plot shows maximal yearly reproduction as a function of time-scaled survival (Tp, where T is the age of maturity). p is estimated as yearly survival raised to the power of the age of maturity. From Witting (1997).


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