Adaptive foraging in the Anthropocene: can individual diet specialization compensate for biotic homogenization?

Biotic homogenization is a ubiquitous consequence of human disturbance. Through a mix of local extinctions and invasions, diverse communities of specialists are often replaced by or inundated with generalist species, resulting in uncertain consequences for ecological functions. While concern about biotic homogenization is growing, intraspecific variation and individual diet specialization (IS) have also emerged as key drivers of ecological functions. The niche variation hypothesis predicts that when a population is released from interspecific competition (ie "ecological release"), intraspecific competition will promote resource niche expansion and IS. It then follows that if biotic homogenization reduces taxonomic diversity and interspecific competition, intraspecific competition within the remaining taxa should expand population resource niches and increase the prevalence of IS. Here, we integrate the rapidly growing fields of biotic homogenization and intraspecific variation and assess the potential for generalist species to compensate for multiple forms of biotic homogenization via adaptive foraging, resource niche expansion, and IS.