title: Introductions do not compensate for functional and phylogenetic losses following extinctions in insular bird assemblages.
abstract: The ratio of species extinctions to introductions has been comparable for many insular assemblages, suggesting that introductions could have 'compensated' for extinctions. However, the capacity for introduced species to replace ecological roles and evolutionary history lost following extinction is unclear. We investigated changes in bird functional and phylogenetic diversity in the wake of extinctions and introductions across a sample of 32 islands worldwide. We found that extinct and introduced species have comparable functional and phylogenetic alpha diversity. However, this was distributed at different positions in functional space and in the phylogeny, indicating a 'false compensation'. Introduced and extinct species did not have equivalent functional roles nor belong to similar lineages. This makes it unlikely that novel island biotas composed of introduced taxa will be able to maintain ecological roles and represent the evolutionary histories of pre-disturbance assemblages and highlights the importance of evaluating changes in alpha and beta diversity concurrently.
authors.affiliation: Departamento de Ecologia, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, CP 131, 74001-970, Brazil.
authors.forename: Fernando L
authors.initials: FL
authors.lastname: Sobral
authors.affiliation: Cornell Lab of Ornithology, Cornell University, 159 Sapsucker Woods Rd, Ithaca, NY, 14850, USA.
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Lees
authors.affiliation: Departamento de Ecologia, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, CP 131, 74001-970, Brazil.
authors.forename: Marcus V
authors.initials: MV
authors.lastname: Cianciaruso
mesh_terms: D000818:Animals; D044822:Biodiversity; D001717:Birds / Q000502:physiology*; D053476:Extinction, Biological; D058865:Introduced Species; D062312:Islands; D008954:Models, Biological
keywords: Alpha diversity; beta diversity; biological conservation; community assembly; compensation; functional diversity; phylogenetic diversity; species gain; species loss; turnover