Evolution of prudent predation in complex food webs. (1st March 2022)

• Record Type: Journal Article
• Authors: Gutiérrez Al‐Khudhairy, Orestes U.; Rossberg, Axel G.
• Editors: Jordan, Ferenc
• Is Part Of: Ecology letters. Volume 25:Number 5(2022)
• Page Start: 1055
• Page End: 1074
• Publication Date: 2022-03-01
• Subjects: allometric scaling -- analytic theory -- apparent competition -- biogeography -- ecological modelling -- evolution of cooperation -- functional responses -- invasive alien species -- spawner–recruitment relations -- trophic interaction strength; Ecology -- Periodicals; 577
• DOI: 10.1111/ele.13979
• Languages: English
• ISSNs: 1461-023X

Abstract

Abstract: Prudent predators catch sufficient prey to sustain their populations but not as much as to undermine their populations' survival. The idea that predators evolve to be prudent has been dismissed in the 1970s, but the arguments invoked then are untenable in the light of modern evolution theory. The evolution of prudent predation has repeatedly been demonstrated in two‐species predator–prey metacommunity models. However, the vigorous population fluctuations that these models predict are not widely observed. Here we show that in complex model food webs prudent predation evolves as a result of consumer‐mediated ('apparent') competitive exclusion of resources, which disadvantages aggressive consumers and does not generate such fluctuations. We make testable predictions for empirical signatures of this mechanism and its outcomes. Then we discuss how these predictions are borne out across freshwater, marine and terrestrial ecosystems. Demonstrating explanatory power of evolved prudent predation well beyond the question of predator–prey coexistence, the predicted signatures explain unexpected declines of invasive alien species, the shape of stock–recruitment relations of fish, and the clearance rates of pelagic consumers across the latitudinal gradient and 15 orders of magnitude in body mass. Specific research to further test this theory is proposed. Abstract : The authors propose a new theory explaining how predators can evolve to catch sufficient prey to sustain their populations but not as much as to undermine their populations' survival. The key mechanism is consumer‐mediated ("apparent'") competitive exclusion of resources, which disadvantages aggressive predators in the metacommunity context by leaving them vulnerable to sudden extirpation in local communities. Testable empirical signatures of this mechanism and its outcomes include known but hitherto unexplained phenomena in fisheries science, invasion ecology, and the study of allometric scaling laws.