Directed endozoochorous dispersal by scavengers facilitate sexual reproduction in otherwise clonal plants at cadaver sites

Ecology and Evolution

Rakel Blaalid¹  Mie Prik Arnberg²  Amy Elizabeth Eycott²  Sam M. J. G. Steyaert²  Marie Louise Davey³  Shane C. Frank⁴ 

[1] Department of Natural History University Museum of Bergen Bergen Norway;Faculty of Biosciences and Aquaculture Nord University Steinkjer Norway;Norwegian Institute for Nature Research Trondheim Norway;University of South‐Eastern Norway Bø Norway;

关键词: cadaver decomposition island;    directed dispersal;    Ericaceae;    recruitment window of opportunity;    reproductive paradox;   

DOI  :  10.1002/ece3.8503

来源: DOAJ

【 摘 要 】

Abstract The regeneration niche of many plant species involves spatially and temporally unpredictable disturbances, called recruitment windows of opportunity. However, even species with clear dispersal adaptations such as fleshy berries may not successfully reach such elusive regeneration microsites. Ericaceous, berry‐producing species in the northern hemisphere demonstrate this dispersal limitation. They are said to display a reproductive paradox owing to their lack of regeneration in apparently suitable microsites despite considerable investment in producing large quantities of berries. Cadavers generate vegetation‐denuded and nutrient‐rich disturbances termed cadaver decomposition islands (CDIs). Cadavers attract facultative scavengers with considerable capacity for endozoochorous seed dispersal. We hypothesize that CDIs facilitate recruitment in berry‐producing ericaceous species due to endozoochorous dispersal directed toward favorable microsites with low competition. We examined seedling establishment within a permanent, semi‐regular 10 × 10 m grid across an ungulate mass die‐off on the Hardangervidda plateau in southeastern Norway. Competing models regarding the relative importance of factors governing recruitment were evaluated, specifically cadaver location (elevated seed rain) and microsite conditions (competition). We found that CDIs did facilitate seedling establishment, as cadaver density was the best predictor of seedling distribution. Other important factors governing seedling establishment such as percentage cover of soil and vascular plants alone were inadequate to explain seedling establishment. Synthesis: This study provides a novel understanding of sexual reproduction in species with cryptic generative reproduction. The directed nature of endozoochorous dispersal combined with long‐distance dispersal abilities of medium to large vertebrate scavengers toward cadavers allows plants to exploit the advantageous but ephemeral resource provided by CDIs.

【 授权许可】

Unknown