Functional diversity among seed dispersal kernels generated by carnivorous mammals

SummaryUnderstanding cascading effects of species loss is a major challenge for ecologists. Traditionally, the robustness of ecological networks has been evaluated based on simulation studies where primary extinctions occur at random or as a function of species specialization, ignoring other important biological factors. Here, we estimate the robustness of a seed dispersal network from a grassland–forest mosaic in southern Brazil, simulating distinct scenarios of woody plant species extinction, including scenarios where species are eliminated based on their evolutionary and functional distinctiveness. Our results suggest that the network is more robust when species are eliminated based on their evolutionary uniqueness, followed by random extinctions, the extinction of the most specialist species, functional distinctiveness and, at last, when the most generalist species are sequentially eliminated. Our results provide important information for grassland–forest mosaic management, as they indicate that loss of generalist species and functional diversity makes the system more likely to collapse.

Download Full-text

Projected impacts of climate change on functional diversity of frugivorous birds along a tropical elevational gradient

Scientific Reports ◽

10.1038/s41598-019-53409-6 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 6

Author(s):

Irene M. A. Bender ◽

W. Daniel Kissling ◽

Katrin Böhning-Gaese ◽

Isabell Hensen ◽

Ingolf Kühn ◽

...

Keyword(s):

Climate Change ◽

Seed Dispersal ◽

Functional Diversity ◽

Bird Species ◽

Elevational Gradient ◽

Frugivorous Birds ◽

Bird Assemblages ◽

Functional Changes ◽

Frugivorous Bird ◽

Functional Dispersion

AbstractClimate change forces many species to move their ranges to higher latitudes or elevations. Resulting immigration or emigration of species might lead to functional changes, e.g., in the trait distribution and composition of ecological assemblages. Here, we combined approaches from biogeography (species distribution models; SDMs) and community ecology (functional diversity) to investigate potential effects of climate-driven range changes on frugivorous bird assemblages along a 3000 m elevational gradient in the tropical Andes. We used SDMs to model current and projected future occurrence probabilities of frugivorous bird species from the lowlands to the tree line. SDM-derived probabilities of occurrence were combined with traits relevant for seed dispersal of fleshy-fruited plants to calculate functional dispersion (FDis; a measure of functional diversity) for current and future bird assemblages. Comparisons of FDis between current and projected future assemblages showed consistent results across four dispersal scenarios, five climate models and two representative concentration pathways. Projections indicated a decrease of FDis in the lowlands, an increase of FDis at lower mid-elevations and little changes at high elevations. This suggests that functional dispersion responds differently to global warming at different elevational levels, likely modifying avian seed dispersal functions and plant regeneration in forest ecosystems along tropical mountains.

Download Full-text

Quantifying seed dispersal kernels from truncated seed-tracking data

Methods in Ecology and Evolution ◽

10.1111/j.2041-210x.2011.00183.x ◽

2011 ◽

Vol 3 (3) ◽

pp. 595-602 ◽

Cited By ~ 18

Author(s):

Ben T. Hirsch ◽

Marco D. Visser ◽

Roland Kays ◽

Patrick A. Jansen

Keyword(s):

Seed Dispersal ◽

Tracking Data ◽

Dispersal Kernels

Download Full-text

Seed dispersal patterns in a temperate forest during a mast event: performance of alternative dispersal kernels

Oecologia ◽

10.1007/s00442-008-1218-4 ◽

2008 ◽

Vol 159 (2) ◽

pp. 389-400 ◽

Cited By ~ 38

Author(s):

Isabel Martínez ◽

Fernando González-Taboada

Keyword(s):

Seed Dispersal ◽

Temperate Forest ◽

Dispersal Patterns ◽

Dispersal Kernels

Download Full-text

Connecting regional-scale tree distribution models with seed dispersal kernels

Applied Mathematics and Computation ◽

10.1016/j.amc.2021.126591 ◽

2022 ◽

Vol 412 ◽

pp. 126591

Author(s):

Ram C. Neupane ◽

James A. Powell ◽

Thomas C. Edwards

Keyword(s):

Seed Dispersal ◽

Regional Scale ◽

Distribution Models ◽

Tree Distribution ◽

Dispersal Kernels

Download Full-text

How does the functional diversity of frugivorous birds shape the spatial pattern of seed dispersal? A case study in a relict plant species

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2015.0280 ◽

2016 ◽

Vol 371 (1694) ◽

pp. 20150280 ◽

Cited By ~ 12

Author(s):

Jessica E. Lavabre ◽

Luis J. Gilarranz ◽

Miguel A. Fortuna ◽

Jordi Bascompte

Keyword(s):

Seed Dispersal ◽

Spatial Pattern ◽

Functional Diversity ◽

Seed Rain ◽

Local Network ◽

Modular Organization ◽

Long Distance ◽

Frugivorous Birds ◽

Dispersal Events

Genetic markers used in combination with network analysis can characterize the fine spatial pattern of seed dispersal and assess the differential contribution of dispersers. As a case study, we focus on the seed dispersal service provided by a small guild of frugivorous birds to the common yew, Taxus baccata L., in southern Spain. We build the spatial networks of seed dispersal events between trees and seed-plots within the studied population—local network—and the spatial network that includes all dispersal events—regional network. Such networks are structured in well-defined modules, i.e. groups of tightly connected mother trees and seed-plots. Neither geographical distance, nor microhabitat type explained this modular structure, but when long-distance dispersal events are incorporated in the network it shows a relative increase in overall modularity. Independent field observations suggested the co-occurrence of two complementary groups, short- and long-distance dispersers, mostly contributing to the local and regional seed rain, respectively. The main long-distance disperser at our site, Turdus viscivorus , preferentially visits the most productive trees, thus shaping the seed rain at the landscape scale and affecting the local modular organization. We end by discussing how DNA barcoding could serve to better quantify the role of functional diversity.

Download Full-text

Loss of generalist plant species and functional diversity decreases the robustness of a seed dispersal network

10.1101/187179 ◽

2017 ◽

Cited By ~ 1

Author(s):

Vinicius A. G. Bastazini ◽

Vanderlei J. Debastiani ◽

Bethânia O. Azambuja ◽

Paulo R. Guimarães ◽

Valério D. Pillar

Keyword(s):

Seed Dispersal ◽

Plant Species ◽

Functional Diversity ◽

Woody Plant ◽

Simulation Studies ◽

Biological Factors ◽

Generalist Species ◽

Cascading Effects ◽

Forest Mosaic ◽

Specialist Species

SummaryUnderstanding cascading effects of species loss has become a major challenge for ecologists. Traditionally, the robustness of ecological networks has been evaluated based on simulation studies where primary extinctions occur at random or as a function of species specialization, ignoring other important biological factors. Here, we estimate the robustness of a seed dispersal network from a grassland–forest mosaic in southern Brazil, simulating distinct scenarios of woody plant species extinction, including scenarios where species are eliminated based on their evolutionary and functional distinctiveness. Our results suggest that the network is more robust when species are eliminated based on their evolutionary uniqueness, followed by random extinctions, the extinction of the most specialist species, functional distinctiveness and, at last, when the most generalist species are sequentially eliminated. Our results provide important information for grassland–forest mosaic management, as they indicate that loss of generalist species and functional diversity makes the system more likely to collapse.

Download Full-text