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Abstract and Figures

The typical generalist diet of most seed dispersers opens a window of opportunity to the invasion of alien plants. Fleshy-fruits show a diverse combination of traits that allow them to interact with seed dispersers. The outcome of the new relationships established between alien plant species and native fruit-eating animals depends both on attributes of the invader and of the mutualist partners in the native community. Two contrasting hypotheses attempt to explain the integration of exotic species in native communities. Darwin’s naturalization hypothesis (DNH) proposes that alien species that are more different from native species are more likely to integrate in the community. The similarity hypothesis (SH) proposes the opposite idea, that is: alien species that are more similar to native species are more likely to integrate the native community. By comparing chemical and morphological traits of 11 alien and 49 native fleshy-fruited species, we tested DNH and SH as assembly rules of alien species in subtropical Andean forests. We did not find differences in most chemical or morphological traits betweenf alien and native fruit species.. The multidimensional variation of alien fruit traits was nested within that of native species. However, alien fruits tended to score high in the range of variation of native chemical traits, suggesting that fruit-eating birds could promote the dispersal of alien species that display high values ot the traits selected by birds. The striking similarity in fruit traits between alien and native species highlights the potential role of seed dispersers as ecological filters of the invasion of alien plants. In turn, this similarity suggests that alien fruits can be functionally equivalent to native ones in terms of their interaction with fruit-eating birds.
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ORIGINAL PAPER
Being popular or freak: how alien plants integrate
into native plant-frugivore networks
Tobias Nicolas Rojas .Marı
´a Cecilia Fa
´tima Gallo .David Lautaro Vergara-Tabares .
Marı
´a Gabriela Nazaro .Iris Catiana Zampini .Marı
´a Ine
´s Isla .
Pedro G. Blendinger
Received: 30 May 2018 / Accepted: 27 April 2019 / Published online: 2 May 2019
Springer Nature Switzerland AG 2019
Abstract The generalist diet of most frugivores
opens a window of opportunity to the invasion of alien
plants whit fleshy-fruits. The outcome of the new
relationships between alien plants and native frugi-
vores depends both on traits of the invaders and of the
mutualist partners in the recipient community. Two
contrasting hypotheses attempt to explain the integra-
tion of alien species in native communities. ‘‘Darwin’s
naturalization hypothesis’’ proposes that alien species
more different from native species are more likely to
integrate in the community. The ‘‘similarity hypoth-
esis’’ proposes the opposite, that alien species more
similar to native species are more likely to integrate
the native community. By comparing chemical and
morphological traits of 12 alien and 48 native fleshy-
fruited species, we tested both hypothesis as assembly
rules of alien species in subtropical Andean forests.
We did not find differences in most chemical or
morphological traits between alien and native fruit
species. The multidimensional variation of alien fruit
traits was nested within that of native species.
However, alien fruits tended to score high in the range
of variation of native chemical traits. Accordingly, we
propose the ‘‘fraction similarity hypothesis’’ as a main
Electronic supplementary material The online version of
this article (https://doi.org/10.1007/s10530-019-01997-9) con-
tains supplementary material, which is available to authorized
users.
T. N. Rojas (&)M. G. Nazaro P. G. Blendinger
Instituto de Ecologı
´a Regional, Universidad Nacional de
Tucuma
´n & CONICET, CC 34, 4107 Yerba Buena,
Tucuma
´n, Argentina
e-mail: tobiasnrojas@gmail.com
M. C. F. Gallo
Instituto de Biotecnologı
´a Farmace
´utica Y Alimentaria,
Universidad Nacional de Tucuma
´n & CONICET, Av.
Kirchner 1900, 4000 San Miguel de Tucuma
´n , Tucuma
´n,
Argentina
D. L. Vergara-Tabares
Instituto de Diversidad Y Ecologı
´a Animal, Universidad
Nacional de Co
´rdoba & CONICET, Ve
´lez Sarsfield 299,
5000 Co
´rdoba, Argentina
I. C. Zampini M. I. Isla
Instituto de Bioprospeccio
´n Y Fisiologı
´a Vegetal,
Universidad Nacional de Tucuma
´n & CONICET, San
Lorenzo 1469, 4000 San Miguel de Tucuma
´n, Tucuma
´n,
Argentina
I. C. Zampini M. I. Isla P. G. Blendinger
Facultad de Ciencias Naturales e Instituto Miguel Lillo,
Universidad Nacional de Tucuma
´n, Miguel Lillo 2005,
4000 San Miguel de Tucuma
´n, Tucuma
´n, Argentina
123
Biol Invasions (2019) 21:2589–2598
https://doi.org/10.1007/s10530-019-01997-9(0123456789().,-volV)(0123456789().,-volV)
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... The invasion process and success of avian-dispersed invasive alien plants are influenced by plant morphological (Gosper and Vivian-Smith 2009), chemical Blendinger et al. 2016) and phenological traits (Marciniak et al. 2020;Nogueira et al. 2020). Certain traits favour bird-fruit interaction and allow plants to integrate into native seed-dispersal networks (Rojas et al. 2019;Marciniak et al. 2020). For example, plants that produce large fruit crop sizes have a high potential to be consumed by birds (Blendinger and Villegas 2011). ...
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