Cause and effect in the natural selection of the population ecological life histories of mammals

A new bioRxiv preprint reconciles 73% of the inter-specific variation in the population ecological life histories of 4,936 species of mammals.

The study is based on the natural selection of mass, as it unfolds from the population dynamic feedback of density dependent interactive competition. This explains the majority of the inter-specific variation in the body masses, life histories, and ecological traits from the inter-specific variation in resource handling, mortality, and interactive competition (Fig. 1).

This selection of mass selects allometric scaling by avoiding extra metabolic costs and maintaining net energy and optimal foraging during the selection mass. Traditional scaling hypotheses---like West et al. (1997) that explain metabolic scaling from a physiology that adapts, or scales, to unexplained body mass variation---are not needed because the metabolic allometry is explained already by the natural selection of mass.

Fig. 1 The decomposition of life history variation across, and within, 27 orders of mammals. 90% intervals (black bars) and limits (dashed lines) of traits across orders, including the residual variation that is unexplained by resource handling (blue), residual adult mortality (yellow), residual juvenile survival (purple), residual metabolism (green), and residual interactive competition (red). For details see Witting (2024).

References

• West, G.B., J.H. Brown and B.J. Enquist 1997. A general model for the origin of allometric scaling laws in biology. Science 276:122--126.
• Witting, L. 2024. Cause and effect in the natural selection of the population ecological life histories of mammals. Preprint in prep for bioRxiv .