The role of fruit heteromorphism in the naturalization of Asteraceae

Abstract

Background and Aims Fruit heteromorphism is considered to be a bet-hedging strategy to cope with spatially or temporally heterogeneous environments. The different behaviours of the fruit morphs of the same species might also be beneficial during naturalization, once the species has been introduced to a new range. Yet, no study to date has tested the association between fruit heteromorphism and global-scale naturalization success for a large set of plant species. Methods We compiled two large datasets on fruit heteromorphism in Asteraceae. One dataset was on native species in Central Europe (n = 321) and the other was on species frequently planted as ornamentals (n = 584). Using phylogenetic linear and logistic regressions, we tested whether heteromorphic species are more likely to naturalize outside their native range, and in more regions of the world than monomorphic species. We also tested whether the effect of heteromorphism is modulated by life history and height of the species. Key Results We show that heteromorphic species were more likely to naturalize outside their native range. However, among the naturalized species, heteromorphic and monomorphic species did not differ in the number of world regions where they became naturalized. A short life span and tall stature both promoted naturalization success and, when life history and height were included in the models, the effect of fruit heteromorphism on the ability to naturalize became non-significant. Nevertheless, among tall plants, heteromorphic ornamental species were significantly more likely to become naturalized in general and in more regions than monomorphic species. Conclusions Our results provide evidence that in Asteraceae the production of heteromorphic fruits is associated with naturalization success. It appears, however, that not fruit heteromorphism per se, but a successful combination of other biological traits in fruit heteromorphic species, namely short life span and tall stature, contributes to their naturalization success.

Facultative mycorrhizal associations promote plant naturalization worldwide

“…The database includes 482 mainland regions and 361 islands (van Kleunen et al 2015a. Specifically, we determined (1) whether a species is capable of naturalization and hence is included in the GloNAF database (naturalization incidence), and for those that are, (2) in how many regions they occur (naturalization extent; as in Razanajatovo et al 2016, Guo et al 2018, Fenesi et al 2019). To be included in GloNAF, a species needs to be reported as naturalized (according to criteria of Richardson et al 2000b, Blackburn et al 2011) in at least one region of the world.…”

“…To be included in GloNAF, a species needs to be reported as naturalized (according to criteria of Richardson et al 2000b, Blackburn et al 2011) in at least one region of the world. Specifically, we determined (1) whether a species is capable of naturalization and hence is included in the GloNAF database (naturalization incidence), and for those that are, (2) in how many regions they occur (naturalization extent; as in Razanajatovo et al 2016, Guo et al 2018, Fenesi et al 2019. In total, there were 3211 naturalized species with information on mycorrhizal type and status in the empirical dataset and 13,791 naturalized species with information on mycorrhizal type in the taxonomic dataset; the 4200 non-naturalized species with information on mycorrhizal type and status were applicable to both datasets (see Fig.…”

“…We measured naturalization success in two ways: (1) whether a species is recorded as naturalized anywhere in the world (naturalization incidence), and (2) if so, how widespread/successful it is (naturalization extent). This approach has been successfully used in previous studies testing the relationships between traits and global naturalization success, as it has revealed that factors related to likelihood of naturalizing per se may differ from those related to how widely naturalized a species is (Razanajatovo et al 2016, Fenesi et al 2019.…”

Inter-Annual Climate Differences Supersede Grazing Effects on the Anatomy and Physiology of a Dominant Grass Species.

“…These dominant grasses thrive in their native habitats because each has evolved specialized functional traits as mechanisms of persistence within each region's disturbance regimes (Anderson 2006; Jardine et al 2021). These adaptations include but are not limited to: 1) large shallow rooting systems comprised of ne roots that quickly absorb water (Nippert and Knapp 2007;Nippert et al 2012); 2) belowground meristematic tissues ("bud banks") which provide new growth after senescence, re, and grazing (Dalgleish and Hartnett 2006;Ott and Hartnett 2015;Ott et al 2019); and 3) specialized leaf morphology and anatomy to maximize light capture and minimize water loss to combat drought (Hameed et al 2012;Nunes et al 2020). While these functional traits aid our understanding as to the continued success of grass species in their respective region, less is understood about how these traits vary, and morphological and physiological adaptations offer the same advantages across sites with varying local climates, yet all within the same broad geographic region.…”

Variation in morphological traits affects dispersal and seedling emergence in dispersive diaspores of Geropogon hybridus

“…Heterocarpy, the production of two or more types of diaspores associated with different dispersal capabilities, has been thoroughly studied at both the interspecific and intraspecific levels (Imbert, ; Matilla et al., ). Although heterocarpy has been described for only a few families (mainly for the Asteraceae; Imbert, ; Fenesi et al., ), it occupies a central place in the literature on the evolution of dispersal, with dispersal rate (i.e., proportion of dispersive diaspores) serving as the main depiction of dispersal strategy in both theoretical and empirical studies (Mazer and Lowry, ; Mandák and Pyšek, ; Hughes, ). However, variation in dispersal traits within a seed type (especially dispersive type) is usually overlooked, despite the fact that such variation may significantly affect dispersal potential and enact an even wider range of dispersal strategies.…”