How do primates affect seed germination? A meta‐analysis of gut passage effects on neotropical plants
Tóm tắt
Biotic seed dispersal is a key process maintaining biodiversity in tropical forests where most trees produce vertebrate‐dispersed seeds. Existing meta‐analyses suggest an overall positive effect of vertebrate gut passage on seed germination, but no significant effects for non‐flying mammals. However, previous meta‐analyses combined rodents (seed predators) and primates (seed dispersers) into the non‐flying mammals category, which may confound specific effects of each group on seed germination. However positive effects of monkeys on germination had previously been found in some studies. Here we disentangle the role of Neotropical primates as contributors to seed dispersal in tropical forests by running a meta‐analysis to determine the overall magnitude of gut passage effects on seed germination percentage and mean time to germination. We also compare effect sizes as a function of different feeding guilds, gut complexities, and seed size. Our results show a strong, positive effect of primates on seed germination percentage and on the number of days to first germination. Strictly frugivorous monkeys, the group most threatened by extinction, showed the highest dispersal quality, increasing germination percentage by 75%. Primates that include insects in their diets had no average effect on germination percentage or time. Gut passage had different outcomes on seeds with different sizes; both large and small seeds showed similar increases in germination percentages after gut passage, but only large seeds germinated faster than control seeds after gut passage. Our results show a relevant role for primates in providing high seed dispersal quality and as drivers of forest regeneration. The combined effects of defaunation and forest fragmentation may result in decreased regeneration of trees, which has the potential to affect negatively both forest structure and ecosystem processes. Finally, we provide general guidelines for standardizing research on seed dispersal by primates.
Consuming fleshy fruits and dispersing seeds is the main ecological service provided by vertebrates to plants. Vertebrate increases seed germination due to treatment given during digestive system passage. Previous meta‐analyses suggest an overall positive effect of vertebrate gut passage on germination, but no insights are available on its variation among different functional groups of mammals. Our analyses indicated that gut passage by Neotropical primates increased seed germination. Strict frugivores, the ones most threatened by extinction, were the most efficient. Our results show a relevant role for primates in providing high seed dispersal quality and as drivers of forest regeneration, which can be meaningful for conservation in a community scale.
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Tài liệu tham khảo
Baskin C, 2014, Seeds: ecology, biogeography and evolution of dormancy and germination
Delouche J. C, 1962, The tetrazolium test for seed viability
Dirzo R., 1991, Plant–animal interactions: evolutionary ecology in tropical and temperate regions, 273
Dirzo R., 2007, The plight of large animals in tropical forests and the consequences for plant regeneration, Biotropica, 39, 289, 10.1111/j.1744-7429.2007.00293.x
Herrera C. M, 2002, Plant–animal interactions: an evolutionary approach, 185
Hladik C. M, 1978, The ecology of arboreal folivores, 373
Kay R. F, 1984, Adaptations for foraging in nonhuman primates: contributions to an organismal biology of prosimians, monkeys, and apes, 21, 10.7312/rodm90184-003
Lorenzi H, 1998, Árvores Brasileiras
Norconk M. A., 2009, Primates: comparative perspectives in the study of behavior, ecology and conservation, 279
Rosenberg M. S, 2000, MetaWin: statistical software for meta‐analysis, ver. 2.0
Royal Botanic Gardens Kew2014.Seed Information Database (SID). Ver. 7.1. <http://data.kew.org/sid/> (September 2014).
Ruxton G, 2010, Experimental design for the life sciences
Traveset A., 2002, Frugivores and seed dispersal: ecological, evolutionary and conservation issues, 339
Traveset A., 2007, Seed dispersal: theory and its application in a changing world, 79