We here describe the multiple mechanisms by which ungulates distribute diaspores across landscapes. There are three primary and three secondary seed dispersal mechanisms by which ungulate dispersal agents contribute to the spread of plant diaspores, both with and without the intervention of other biotic and abiotic agents. These dispersal mechanisms may be combined in successive interdependent steps. Native, introduced and domestic ungulates co-occur in many ecosystems and frequently interact with numerous plant species, which facilitates long-distance dispersal of both native and exotic plants. However, ungulate taxonomic diversity conceals a much higher diversity in terms of the functional traits involved in ungulate-mediated dispersal (e.g., feeding regime, fur morphology). These traits may strongly affect emigration, transfer and immigration in the animal-mediated plant dispersal, and consequently; they may also impact overall seed dispersal effectiveness, both quantitatively and qualitatively. In this review, we compare internal mechanisms, where seeds must survive digestive treatments (regurgitation, endozoochory), with external mechanisms, where diaspores are carried on the outside of the vectors (epizoochory). We include both primary epizoochory (direct adhesion to fur essentially) and secondary epizoochory (diaspore-laden mud adhering to hooves or the body and, transfer through contact with a conspecific). We addressed the overlap/complementarity of ungulates for the plant species they disperse through a systematic literature review. When two ungulate species co-occur, there is always an overlap in the plant species dispersed by endozoochory or by fur-epizoochory. Further, when we consider the proportion of plant species dispersed both internally and externally by an ungulate, the overlap is higher for grazing than browsing ungulates. We identify two challenges for the field of dispersal ecology: the proportion of all diaspores produced that are carried over long distances by ungulates, and the relative importance of ungulates on the whole as the main dispersal agent for plants. Furthermore, the fact that numerous plants dispersed by fur-epizoochory do not feature any specific adaptations is intriguing. We discuss unsolved methodological challenges and stress research perspectives related to ungulate-mediated dispersal: for example, taking animal behavior and cognition into account and studying how ungulates contribute to the spread of invasive exotic plants and altitudinal plant dispersal.

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Green chemistry, which aims at the development of efficient methods for the synthesis of nanoparticles, is a relatively new emerging field of nanotechnology, which has economic and environment‐friendly benefits over chemical and physical processes. The present work was carried out to develop silver nanoparticles (Ag‐NPs) using the plant (Achillea millefolium or yarrow) aqueous extract as both a reducing and capping agent under the green synthesis method. Characterization of synthesized Ag‐NPs was done using IR spectroscopy, scanning electron microscopy (SEM), X‐ray diffraction (XRD), and ultraviolet–visible (UV–vis). The UV–vis spectrum showed the maximum absorbance at around 440–470 nm, which suggested the formation of green synthesized Ag‐NPs. The morphological study demonstrated that the Ag‐NPs were spherical in shape with an average size of 22.4 ± 7.4 nm. The antimicrobial activities of Ag‐NPs against Fusarium and Aspergillus niger species of fungal and Escherichia coli species of bacteria were investigated through the disc diffusion and well‐diffusion method using their zone of inhibition. The cytotoxicity effect of Ag‐NPs on cell lines MOLT‐4 was evaluated by using MTT assay. These nanoparticles showed remarkable antimicrobial activity against bacterias and fungus in low concentration. The cytotoxicity studies showed that IC50 of green synthesized Ag‐NPs was 0.011 µm in comparison to 1.8 for Cisplatin which more active than anticancer drug for MOLT‐4 cell line. The results showed that the green synthesized Ag‐NPs are expected to have notable applications and can be potentially useful in pharmaceutical and biomedical applications.

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