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Teng SN, Svenning JC, Xu C. Large mammals and trees in eastern monsoonal China: anthropogenic losses since the Late Pleistocene and restoration prospects in the Anthropocene. Biol Rev Camb Philos Soc 2023; 98:1607-1632. [PMID: 37102332 DOI: 10.1111/brv.12968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 04/16/2023] [Accepted: 04/18/2023] [Indexed: 04/28/2023]
Abstract
Massive human-induced declines of large-sized animals and trees (megabiota) from the Late Pleistocene to the Anthropocene have resulted in downsized ecosystems across the globe, in which components and functions have been greatly simplified. In response, active restoration projects of extant large-sized species or functional substitutes are needed at large scales to promote ecological processes that are important for ecosystem self-regulation and biodiversity maintenance. Despite the desired global scope of such projects, they have received little attention in East Asia. Here, we synthesise the biogeographical and ecological knowledge of megabiota in ancient and modern China, with relevant data mostly located in eastern monsoonal China (EMC), aiming to assess its potential for restoring functionally intact ecosystems modulated by megabiota. We found that during the Late Pleistocene, 12 mammalian megafaunal (carnivores ≥15 kg and herbivores ≥500 kg) species disappeared from EMC: one carnivore Crocuta ultima (East Asian spotted hyena) and 11 herbivores including six megaherbivores (≥1000 kg). The relative importance of climate change and humans in driving these losses remains debated, despite accumulating evidence in favour of the latter. Later massive depletion of megafauna and large-sized (45-500 kg) herbivores has been closely associated with agricultural expansion and societal development, especially during the late Holocene. While forests rich in large timber trees (33 taxa in written records) were common in the region 2000-3000 years ago, millennial-long logging has resulted in considerable range contractions and at least 39 threatened species. The wide distribution of C. ultima, which likely favoured open or semi-open habitats (like extant spotted hyenas), suggests the existence of mosaic open and closed vegetation in the Late Pleistocene across EMC, in line with a few pollen-based vegetation reconstructions and potentially, or at least partially, reflecting herbivory by herbivorous megafauna. The widespread loss of megaherbivores may have strongly compromised seed dispersal for both megafruit (fleshy fruits with widths ≥40 mm) and non-megafruit plant species in EMC, especially in terms of extra-long-distance (>10 km) dispersal, which is critical for plant species that rely on effective biotic agents to track rapid climate change. The former occurrence of large mammals and trees have translated into rich material and non-material heritages passed down across generations. Several reintroduction projects have been implemented or are under consideration, with the case of Elaphurus davidianus a notable success in recovering wild populations in the middle reaches of the Yangtze River, although trophic interactions with native carnivorous megafauna have not yet been restored. Lessons of dealing with human-wildlife conflicts are key to public support for maintaining landscapes shared with megafauna and large herbivores in the human-dominated Anthropocene. Meanwhile, potential human-wildlife conflicts, e.g. public health risks, need to be scientifically informed and effectively reduced. The Chinese government's strong commitment to improved policies of ecological protection and restoration (e.g. ecological redlines and national parks) provides a solid foundation for a scaling-up contribution to the global scope needed for solving the crisis of biotic downsizing and ecosystem degradation.
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Affiliation(s)
- Shuqing N Teng
- School of Life Sciences, Nanjing University, Nanjing, 210023, China
| | - Jens-Christian Svenning
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, 8000, Denmark
| | - Chi Xu
- School of Life Sciences, Nanjing University, Nanjing, 210023, China
- Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in northwestern China of Ministry of Education, Ningxia University, Yinchuan, 750021, China
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2
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Prakash H, Kumar RS, Lahkar B, Sukumar R, Vanak AT, Thaker M. Animal movement ecology in India: insights from 2011-2021 and prospective for the future. PeerJ 2022; 10:e14401. [PMID: 36530402 PMCID: PMC9756863 DOI: 10.7717/peerj.14401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 10/25/2022] [Indexed: 12/15/2022] Open
Abstract
The field of animal movement ecology has advanced by leaps and bounds in the past few decades with the advent of sophisticated technology, advanced analytical tools, and multiple frameworks and paradigms to address key ecological problems. Unlike the longer history and faster growth of the field in North America, Europe, and Africa, movement ecology in Asia has only recently been gaining momentum. Here, we provide a review of the field from studies based in India over the last 11 years (2011-2021) curated from the database, Scopus, and search engine, Google Scholar. We identify current directions in the research objectives, taxa studied, tracking technology and the biogeographic regions in which animals were tracked, considering the years since the last systematic review of movement ecology research in the country. As an indication of the growing interest in this field, there has been a rapid increase in the number of publications over the last decade. Class Mammalia continues to dominate the taxa tracked, with tiger and leopard being the most common species studied across publications. Invertebrates and other small and medium-sized animals, as well as aquatic animals, in comparison, are understudied and remain among the important target taxa for tracking in future studies. As in the previous three decades, researchers have focussed on characterising home ranges and habitat use of animals. There is, however, a notable shift to examine the movement decision of animals in human-modified landscapes, although efforts to use movement ecology to understand impacts of climate change remain missing. Given the biogeographic and taxonomic diversity of India, and the fact that the interface between anthropogenic activity and wildlife interactions is increasing, we suggest ways in which the field of movement ecology can be expanded to facilitate ecological insights and conservation efforts. With the advancement of affordable technologies and the availability of analytical tools, the potential to expand the field of movement ecology, shift research foci, and gain new insights is now prime.
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Affiliation(s)
- Harish Prakash
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
| | - R Suresh Kumar
- Department of Endangered Species Management, Wildlife Institute of India, Dehradun, Uttarakhand, India
| | | | - Raman Sukumar
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
| | - Abi T Vanak
- Ashoka Trust for Research in Ecology and the Environment, Bengaluru, Karnataka, India.,School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Maria Thaker
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
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3
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Das P, Kshettry A, Kumara HN. Trunk picking from a truncating menu: Dry season forage selection by Asian elephant in a multi-use landscape. PLoS One 2022; 17:e0271052. [PMID: 35802712 PMCID: PMC9269951 DOI: 10.1371/journal.pone.0271052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 06/23/2022] [Indexed: 11/18/2022] Open
Abstract
Elephants show a strong selection towards areas with high foraging opportunities at the landscape level making top-down decisions by first selecting patch types within landscapes and finally species within them. Understanding forage selection in a multi-use landscape is critical for prioritising patches for habitat management, ensuring availability of selected forage, helping in minimizing pressure on food crops and subsequent negative interactions with people. We assessed dry season forage selection in a multi-use landscape of West Bengal state, India. Relative forage use and relative plant species availability ratio were calculated to assess forage selection in a multi-use landscape comprising of the forest, tea estates, agricultural land, and human settlement. Forage use was assessed using the opportunistic feeding trail observation method (150.01 km). Stratified random sampling was used to assess plant species availability using the quadrat method (123 plots of 0.1 ha each). Among 286 plant species recorded, 132 plant species were consumed by elephants. A majority (80.21%) of plant species were consumed more than the proportional availability thereby showing selective foraging during the dry season in the study area. From forest to semi-open forest and open forest, canopy layer tree density and the total number of species decreased whereas invasive species density increased. This indicates the high impact on the forage species availability for elephants and the requirement of appropriate habitat management strategies. The presence of 32.14% of the selected forage species in human-use landscape alone demands the development of conservation interventions. This is the first study to assess forage selection by elephants in a multi-use landscape and used to prioritise conservation and management strategies at a landscape level.
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Affiliation(s)
- Priyanka Das
- Sálim Ali Centre for Ornithology and Natural History, Coimbatore, Tamil Nadu, India
- * E-mail: (PD); (HNK)
| | - Aritra Kshettry
- INSPIRE-Fellow, Department of Science and Technology, Government of India, New Delhi, India
| | - H. N. Kumara
- Sálim Ali Centre for Ornithology and Natural History, Coimbatore, Tamil Nadu, India
- * E-mail: (PD); (HNK)
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4
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Dasanayaka BI, Jinadasa RN, Jayasuriya KMGG, Phartyal SS. Seed ecophysiology of Elephant Apple (
Dillenia indica
)—An important tree species of the Indomalayan realm. Ecol Res 2022. [DOI: 10.1111/1440-1703.12312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Fricke EC, Ordonez A, Rogers HS, Svenning JC. The effects of defaunation on plants' capacity to track climate change. Science 2022; 375:210-214. [PMID: 35025640 DOI: 10.1126/science.abk3510] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Half of all plant species rely on animals to disperse their seeds. Seed dispersal interactions lost through defaunation and gained during novel community assembly influence whether plants can adapt to climate change through migration. We develop trait-based models to predict pairwise interactions and dispersal function for fleshy-fruited plants globally. Using interactions with introduced species as an observable proxy for interactions in future novel seed dispersal networks, we find strong potential to forecast their assembly and functioning. We conservatively estimate that mammal and bird defaunation has already reduced the capacity of plants to track climate change by 60% globally. This strong reduction in the ability of plants to adapt to climate change through range shifts shows a synergy between defaunation and climate change that undermines vegetation resilience.
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Affiliation(s)
- Evan C Fricke
- National Socio-Environmental Synthesis Center, University of Maryland, Annapolis, MD 21401, USA.,Department of BioSciences, Rice University, Houston, TX 77005, USA
| | - Alejandro Ordonez
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark
| | - Haldre S Rogers
- Department of Ecology and Evolutionary Biology, Iowa State University, Ames, IA 50011, USA
| | - Jens-Christian Svenning
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark
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6
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Sengupta A. Animal‐mediated seed dispersal in India: Implications for conservation of India’s biodiversity. Biotropica 2021. [DOI: 10.1111/btp.12982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Asmita Sengupta
- Ashoka Trust for Research in Ecology and the Environment Bangalore Karnataka India
- National Institute of Advanced Studies Bangalore Karnataka India
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7
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Spengler RN, Petraglia M, Roberts P, Ashastina K, Kistler L, Mueller NG, Boivin N. Exaptation Traits for Megafaunal Mutualisms as a Factor in Plant Domestication. FRONTIERS IN PLANT SCIENCE 2021; 12:649394. [PMID: 33841476 PMCID: PMC8024633 DOI: 10.3389/fpls.2021.649394] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 02/25/2021] [Indexed: 05/26/2023]
Abstract
Megafaunal extinctions are recurring events that cause evolutionary ripples, as cascades of secondary extinctions and shifting selective pressures reshape ecosystems. Megafaunal browsers and grazers are major ecosystem engineers, they: keep woody vegetation suppressed; are nitrogen cyclers; and serve as seed dispersers. Most angiosperms possess sets of physiological traits that allow for the fixation of mutualisms with megafauna; some of these traits appear to serve as exaptation (preadaptation) features for farming. As an easily recognized example, fleshy fruits are, an exaptation to agriculture, as they evolved to recruit a non-human disperser. We hypothesize that the traits of rapid annual growth, self-compatibility, heavy investment in reproduction, high plasticity (wide reaction norms), and rapid evolvability were part of an adaptive syndrome for megafaunal seed dispersal. We review the evolutionary importance that megafauna had for crop and weed progenitors and discuss possible ramifications of their extinction on: (1) seed dispersal; (2) population dynamics; and (3) habitat loss. Humans replaced some of the ecological services that had been lost as a result of late Quaternary extinctions and drove rapid evolutionary change resulting in domestication.
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Affiliation(s)
- Robert N. Spengler
- Department of Archaeology, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Michael Petraglia
- Department of Archaeology, Max Planck Institute for the Science of Human History, Jena, Germany
- Department of Anthropology, Smithsonian Institution, National Museum of Natural History, Washington, DC, United States
- School of Social Science, The University of Queensland, Brisbane, QLD, Australia
| | - Patrick Roberts
- Department of Archaeology, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Kseniia Ashastina
- Department of Archaeology, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Logan Kistler
- Department of Anthropology, Smithsonian Institution, National Museum of Natural History, Washington, DC, United States
| | - Natalie G. Mueller
- Department of Archaeology, Washington University in St. Louis, St. Louis, MO, United States
| | - Nicole Boivin
- Department of Archaeology, Max Planck Institute for the Science of Human History, Jena, Germany
- Department of Anthropology, Smithsonian Institution, National Museum of Natural History, Washington, DC, United States
- School of Social Science, The University of Queensland, Brisbane, QLD, Australia
- Department of Anthropology and Archaeology, University of Calgary, Calgary, AB, Canada
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8
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Tan WH, Hii A, Solana‐Mena A, Wong EP, Loke VPW, Tan ASL, Kromann‐Clausen A, Hii N, bin Pura P, bin Tunil MT, A/L Din S, Chin CF, Campos‐Arceiz A. Long‐term monitoring of seed dispersal by Asian elephants in a Sundaland rainforest. Biotropica 2021. [DOI: 10.1111/btp.12889] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Wei Harn Tan
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Adeline Hii
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Alicia Solana‐Mena
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Ee Phin Wong
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
- Management & Ecology of Malaysian Elephants University of Nottingham Malaysia Semenyih Malaysia
| | - Vivienne P. W. Loke
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Ange S. L. Tan
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Anders Kromann‐Clausen
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Ning Hii
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Param bin Pura
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Muhamad Tauhid bin Tunil
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Sudin A/L Din
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
| | - Chiew Foan Chin
- School of Biosciences The University of Nottingham Malaysia Kajang Malaysia
| | - Ahimsa Campos‐Arceiz
- School of Environmental and Geographical Sciences The University of Nottingham Malaysia Kajang Malaysia
- Southeast Asia Biodiversity Research Institute Chinese Academy of Sciences Nay Pyi Taw Myanmar
- Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences Mengla China
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9
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Pedrosa F, Bercê W, Levi T, Pires M, Galetti M. Seed dispersal effectiveness by a large‐bodied invasive species in defaunated landscapes. Biotropica 2019. [DOI: 10.1111/btp.12706] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Felipe Pedrosa
- Department of Ecology Institute of Biosciences São Paulo State University (UNESP) Rio Claro Brazil
- Department of Fisheries and Wildlife Oregon State University Corvallis OR USA
| | - William Bercê
- Department of Ecology Institute of Biosciences São Paulo State University (UNESP) Rio Claro Brazil
| | - Taal Levi
- Department of Fisheries and Wildlife Oregon State University Corvallis OR USA
| | - Mathias Pires
- Department of Animal Biology Institute of Biology Campinas State University (UNICAMP) Campinas Brazil
| | - Mauro Galetti
- Department of Ecology Institute of Biosciences São Paulo State University (UNESP) Rio Claro Brazil
- Department of Biology University of Miami Coral Gables FL USA
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10
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Edwards DP, Socolar JB, Mills SC, Burivalova Z, Koh LP, Wilcove DS. Conservation of Tropical Forests in the Anthropocene. Curr Biol 2019; 29:R1008-R1020. [DOI: 10.1016/j.cub.2019.08.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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11
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McConkey KR, Nathalang A, Brockelman WY, Saralamba C, Santon J, Matmoon U, Somnuk R, Srinoppawan K. Different megafauna vary in their seed dispersal effectiveness of the megafaunal fruit Platymitra macrocarpa (Annonaceae). PLoS One 2018; 13:e0198960. [PMID: 30020929 PMCID: PMC6051586 DOI: 10.1371/journal.pone.0198960] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 05/28/2018] [Indexed: 11/18/2022] Open
Abstract
The world’s largest terrestrial animals (megafauna) can play profound roles in seed dispersal. Yet, the term ‘megafauna’ is often used to encompass a diverse range of body sizes and physiologies of, primarily, herbivorous animals. To determine the extent to which these animals varied in their seed dispersal effectiveness (SDE), we compared the contribution of different megafauna for the large-fruited Platymitra macrocarpa (Annonaceae), in a tropical evergreen forest in Thailand. We quantified ‘seed dispersal effectiveness’ by measuring the quantity and quality contributions of all consumers of P. macrocarpa fruit. Seed dispersal quantity was the proportion of the crop consumed by each species. Quality was defined as the proportion of seeds handled by each animal taxon that survived to produce a 2-month seedling. Megafauna (elephants, sambar deer, bears) dispersed 78% of seeds that produced seedlings, with 21% dispersed by gibbons (a medium-sized frugivore). The main megafaunal consumers displayed different dispersal strategies. Elephants were the most effective dispersers (37% of seedlings) and they achieved this by being high-quality and low-quantity dispersers. Bears displayed a similar strategy but were especially rare visitors to the trees (24% of the total seedlings produced). Sambar were high-quantity dispersers, but most seeds they handled did not survive and they were responsible for only 17% of seedlings. Gibbons displayed a high SDE relative to their body size, but they probably cannot match the role of elephants despite being more regular consumers of the fruit. The low density and poor regeneration of P. macrocarpa in the study site suggest that current dispersal rates by megafauna are insufficient, possibly reflecting reduced or missing megafauna populations. We show that different megafaunal species disperse seeds in different ways and may make unique contributions to the reproductive success of the plant species.
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Affiliation(s)
- Kim R. McConkey
- School of Natural Sciences and Engineering, National Institute of Advanced Studies, Indian Institute of Science Campus, Bangalore, India
- School of Geography, University of Nottingham Malaysia Campus, Semenyih, Selangor, Malaysia
- * E-mail: (KRM); (AN)
| | - Anuttara Nathalang
- Ecology Lab, BIOTEC, National Science and Technology Development Agency, Pathum Thani, Thailand
- * E-mail: (KRM); (AN)
| | - Warren Y. Brockelman
- Ecology Lab, BIOTEC, National Science and Technology Development Agency, Pathum Thani, Thailand
- Institute of Molecular Biosciences, Mahidol University–Salaya, Phutthamonthon, Nakhon Pathom, Thailand
| | - Chanpen Saralamba
- Conservation Biology Program, Mahidol University Kanchanaburi Campus, Sai Yok, Kanchanaburi, Thailand
| | - Jantima Santon
- Ecology Lab, BIOTEC, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Umaporn Matmoon
- Ecology Lab, BIOTEC, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Rathasart Somnuk
- Ecology Lab, BIOTEC, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Kanchit Srinoppawan
- Department of National Parks, Wildlife and Plant Conservation, Chatuchak, Bangkok, Thailand
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13
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Poulsen JR, Rosin C, Meier A, Mills E, Nuñez CL, Koerner SE, Blanchard E, Callejas J, Moore S, Sowers M. Ecological consequences of forest elephant declines for Afrotropical forests. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2018; 32:559-567. [PMID: 29076179 DOI: 10.1111/cobi.13035] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 10/05/2017] [Accepted: 10/12/2017] [Indexed: 06/07/2023]
Abstract
Poaching is rapidly extirpating African forest elephants (Loxodonta cyclotis) from most of their historical range, leaving vast areas of elephant-free tropical forest. Elephants are ecological engineers that create and maintain forest habitat; thus, their loss will have large consequences for the composition and structure of Afrotropical forests. Through a comprehensive literature review, we evaluated the roles of forest elephants in seed dispersal, nutrient recycling, and herbivory and physical damage to predict the cascading ecological effects of their population declines. Loss of seed dispersal by elephants will favor tree species dispersed abiotically and by smaller dispersal agents, and tree species composition will depend on the downstream effects of changes in elephant nutrient cycling and browsing. Loss of trampling and herbivory of seedlings and saplings will result in high tree density with release from browsing pressures. Diminished seed dispersal by elephants and high stem density are likely to reduce the recruitment of large trees and thus increase homogeneity of forest structure and decrease carbon stocks. The loss of ecological services by forest elephants likely means Central African forests will be more like Neotropical forests, from which megafauna were extirpated thousands of years ago. Without intervention, as much as 96% of Central African forests will have modified species composition and structure as elephants are compressed into remaining protected areas. Stopping elephant poaching is an urgent first step to mitigating these effects, but long-term conservation will require land-use planning that incorporates elephant habitat into forested landscapes that are being rapidly transformed by industrial agriculture and logging.
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Affiliation(s)
- John R Poulsen
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
- University Program in Ecology, Duke University, Durham, NC 27708, U.S.A
| | - Cooper Rosin
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
| | - Amelia Meier
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
| | - Emily Mills
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
| | - Chase L Nuñez
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
- University Program in Ecology, Duke University, Durham, NC 27708, U.S.A
| | - Sally E Koerner
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
- Department of Biology, University of North Carolina Greensboro, Greensboro, NC 27412, U.S.A
| | - Emily Blanchard
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
| | - Jennifer Callejas
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
| | - Sarah Moore
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
| | - Mark Sowers
- Nicholas School of the Environment, Duke University, P.O. Box 90328, Durham, NC 27708, U.S.A
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14
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Tew E, Landman M, Kerley GI. The Contribution of the Chacma Baboon to Seed Dispersal in the Eastern Karoo, South Africa. AFRICAN JOURNAL OF WILDLIFE RESEARCH 2018. [DOI: 10.3957/056.048.023002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Eleanor Tew
- Centre for African Conservation Ecology, Nelson Mandela University, Port Elizabeth, 6031 South Africa
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, United Kingdom
| | - Marietjie Landman
- Centre for African Conservation Ecology, Nelson Mandela University, Port Elizabeth, 6031 South Africa
| | - Graham I.H. Kerley
- Centre for African Conservation Ecology, Nelson Mandela University, Port Elizabeth, 6031 South Africa
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15
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Sekar N, Lee CL, Sukumar R. Functional nonredundancy of elephants in a disturbed tropical forest. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2017; 31:1152-1162. [PMID: 28218805 DOI: 10.1111/cobi.12907] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 12/24/2016] [Accepted: 02/12/2017] [Indexed: 06/06/2023]
Abstract
Conservation efforts are often motivated by the threat of global extinction. Yet if conservationists had more information suggesting that extirpation of individual species could lead to undesirable ecological effects, they might more frequently attempt to protect or restore such species across their ranges even if they were not globally endangered. Scientists have seldom measured or quantitatively predicted the functional consequences of species loss, even for large, extinction-prone species that theory suggests should be functionally unique. We measured the contribution of Asian elephants (Elephas maximus) to the dispersal of 3 large-fruited species in a disturbed tropical moist forest and predicted the extent to which alternative dispersers could compensate for elephants in their absence. We created an empirical probability model with data on frugivory and seed dispersal from Buxa Tiger Reserve, India. These data were used to estimate the proportion of seeds consumed by elephants and other frugivores that survive handling and density-dependent processes (Janzen-Connell effects and conspecific intradung competition) and germinate. Without compensation, the number of seeds dispersed and surviving density-dependent effects decreased 26% (Artocarpus chaplasha), 42% (Careya arborea), and 72% (Dillenia indica) when elephants were absent from the ecosystem. Compensatory fruit removal by other animals substantially ameliorated these losses. For instance, reductions in successful dispersal of D. indica were as low as 23% when gaur (Bos gaurus) persisted, but median dispersal distance still declined from 30% (C. arborea) to 90% (A. chaplasha) without elephants. Our results support the theory that the largest animal species in an ecosystem have nonredundant ecological functionality and that their extirpation is likely to lead to the deterioration of ecosystem processes such as seed dispersal. This effect is likely accentuated by the overall defaunation of many tropical systems.
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Affiliation(s)
- Nitin Sekar
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, 08540, U.S.A
- Center for Ecological Sciences, Indian Institute of Science, Bangalore, 560012, India
| | - Chia-Lo Lee
- Electrical Engineering, Princeton University, Princeton, NJ, 08540, U.S.A
| | - Raman Sukumar
- Center for Ecological Sciences, Indian Institute of Science, Bangalore, 560012, India
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Corlett RT. Frugivory and seed dispersal by vertebrates in tropical and subtropical Asia: An update. Glob Ecol Conserv 2017. [DOI: 10.1016/j.gecco.2017.04.007] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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17
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Fritz H. Long-term field studies of elephants: understanding the ecology and conservation of a long-lived ecosystem engineer. J Mammal 2017. [DOI: 10.1093/jmammal/gyx023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Williams EW, Gardner EM, Harris R, Chaveerach A, Pereira JT, Zerega NJC. Out of Borneo: biogeography, phylogeny and divergence date estimates of Artocarpus (Moraceae). ANNALS OF BOTANY 2017; 119:611-627. [PMID: 28073771 PMCID: PMC5458716 DOI: 10.1093/aob/mcw249] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 11/03/2016] [Indexed: 05/14/2023]
Abstract
BACKGROUND AND AIMS The breadfruit genus ( Artocarpus , Moraceae) includes valuable underutilized fruit tree crops with a centre of diversity in Southeast Asia. It belongs to the monophyletic tribe Artocarpeae, whose only other members include two small neotropical genera. This study aimed to reconstruct the phylogeny, estimate divergence dates and infer ancestral ranges of Artocarpeae, especially Artocarpus , to better understand spatial and temporal evolutionary relationships and dispersal patterns in a geologically complex region. METHODS To investigate the phylogeny and biogeography of Artocarpeae, this study used Bayesian and maximum likelihood approaches to analyze DNA sequences from six plastid and two nuclear regions from 75% of Artocarpus species, both neotropical Artocarpeae genera, and members of all other Moraceae tribes. Six fossil-based calibrations within the Moraceae family were used to infer divergence times. Ancestral areas and estimated dispersal events were also inferred. KEY RESULTS Artocarpeae, Artocarpus and four monophyletic Artocarpus subgenera were well supported. A late Cretaceous origin of the Artocarpeae tribe in the Americas is inferred, followed by Eocene radiation of Artocarpus in Asia, with the greatest diversification occurring during the Miocene. Borneo is reconstructed as the ancestral range of Artocarpus , with dozens of independent in situ diversification events inferred there, as well as dispersal events to other regions of Southeast Asia. Dispersal pathways of Artocarpus and its ancestors are proposed. CONCLUSIONS Borneo was central in the diversification of the genus Artocarpus and probably served as the centre from which species dispersed and diversified in several directions. The greatest amount of diversification is inferred to have occurred during the Miocene, when sea levels fluctuated and land connections frequently existed between Borneo, mainland Asia, Sumatra and Java. Many species found in these areas have extant overlapping ranges, suggesting that sympatric speciation may have occurred. By contrast, Artocarpus diversity east of Borneo (where many of the islands have no historical connections to the landmasses of the Sunda and Sahul shelves) is unique and probably the product of over water long-distance dispersal events and subsequent diversification in allopatry. This work represents the most comprehensive Artocarpus phylogeny and biogeography study to date and supports Borneo as an evolutionary biodiversity hotspot.
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Affiliation(s)
- Evelyn W. Williams
- Chicago Botanic Garden, Plant Science and Conservation, 1000 Lake Cook Road, Glencoe, IL 60022, USA
- For correspondence. E-mail ,
| | - Elliot M. Gardner
- Chicago Botanic Garden, Plant Science and Conservation, 1000 Lake Cook Road, Glencoe, IL 60022, USA
- Northwestern University, Plant Biology and Conservation Program, 2205 Tech Dr., Evanston, IL 60208, USA
| | - Robert Harris
- Northwestern University, Plant Biology and Conservation Program, 2205 Tech Dr., Evanston, IL 60208, USA
| | - Arunrat Chaveerach
- Faculty of Science, Genetics and Environmental Toxicology Research Group, Khon Kaen University, 123 Mittraphap Highway, Khon Kaen, 40002, Thailand
| | - Joan T. Pereira
- Forest Research Centre, Sabah Forestry Department, PO Box 407, 90715 Sandakan, Sabah, Malaysia
| | - Nyree J. C. Zerega
- Chicago Botanic Garden, Plant Science and Conservation, 1000 Lake Cook Road, Glencoe, IL 60022, USA
- Northwestern University, Plant Biology and Conservation Program, 2205 Tech Dr., Evanston, IL 60208, USA
- For correspondence. E-mail ,
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19
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Seed dispersal potential of Asian elephants. ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY 2016. [DOI: 10.1016/j.actao.2016.10.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Making dispersal syndromes and networks useful in tropical conservation and restoration. Glob Ecol Conserv 2016. [DOI: 10.1016/j.gecco.2016.03.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Sekar N, Giam X, Sharma NP, Sukumar R. How much Dillenia indica seed predation occurs from Asian elephant dung? ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY 2016. [DOI: 10.1016/j.actao.2015.11.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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