The plant-disperser-fruit pest triads involve 3 interacting animals or groups(plants,vertebrates and seed parasites),and the dispersal of both seeds and seed parasites,which can both benefit from endozoochory via defe...The plant-disperser-fruit pest triads involve 3 interacting animals or groups(plants,vertebrates and seed parasites),and the dispersal of both seeds and seed parasites,which can both benefit from endozoochory via defecation or regurgitation by frugivorous vertebrates.However,we have very limited knowledge about the ecological and evolutionary consequences of these plant-disperser-fruit pest triads.Across central Northern China,several seed wasps(mainly Eurytoma plotnikov attack Pistacia chinensis fruits,and seed wasp larvae can develop,diapause and finally emerge as adults inside a seed during the following 1-3 years.In this study,we experimentally investigated whether frugivorous birds discriminated P.chinesis fruits with or without seed parasites,and whether bird endozoochory(by defecation or regurgitation)affected larval survival of seed parasites.The infestation rate by seed parasites was 37%of the P.chinesis fruit crop but with up to 48%of aborted fruits.We found that all 5 bird species can discriminate and then reject all unhealthy fruits(including aborted and insect-infested).However,4 of the 5 bird species,in particular bulbul species,consumed 15-41%of aborted and insect-infested fruits as complementary food only when these unhealthy fruits were provided.Moreover,all larva of seed parasites remained alive after bird defecation or regurgitation.In conclusion,our study demonstrates that endozoochory by frugivorous birds could lead to potential dispersal of seed parasites of P.chinensis but with a very low probability.展开更多
Aims Melampyrum pratense and M.subalpinum are two myrmeco-chorous species,which possess similar habitat requirements and frequently occur together.Despite this,their population sizes differ markedly.Melampyrum pratens...Aims Melampyrum pratense and M.subalpinum are two myrmeco-chorous species,which possess similar habitat requirements and frequently occur together.Despite this,their population sizes differ markedly.Melampyrum pratense populations are usually very large,whereas M.subalpinum has rather small and isolated populations.We suggest that such an imbalance might be partially influenced by the difference in ant-mediated seed-removal rates.genus Melampyrum is considered to be exclusively myrme-cochorous,though to achieve the recent distribution of some Melampyrum species during the Holocene myrmecochory would be highly insufficient.We suggest that endozoochory takes place in the long-distance migration,whereas myrmecochory is important for the removal of seeds on a local scale.Methods For seed-preference analysis,M.pratense and M.subalpinum mixed seed samples were placed around Formica polyctena anthills.after a period of time,the remaining seeds of both species were counted for each sample.The results were analysed by analysis of variance and generalized linear mixed-effect model.To test myrmecochorous removal distances,M.pratense seeds were covered with fluorescent dactyloscopic powder and placed in the vicinity of a large ant trail.The area around the starting plot was searched in the dark using uV lED torchlight 7 h after the beginning.The distance from the starting plot was measured for each seed found.birds,rodents,leporine and a ruminant were fed with M.pratense seeds and fresh plants to test the possibility of endozoochorous dispersal of the species.animal droppings were searched for intact seeds.Important Findingsour field studies show that from mixed seed samples,containing both species,ants significantly preferred the seeds of M.pratense.This may be one of factors that has positive influence on M.prat-ense success in seed dispersal on mixed stands and consequently in the colonization of favourable sites.Experiments focusing on ant-mediated dispersal distance revealed that F.polyctena ants are able to move seeds over a distance of 36 m in only 7 h.This distance is among the furthest known myrmecochorous removals of forest plant seeds.a new Melampyrum seed disperser Oligolophus tridens(opiliones)was observed repeatedly.our pilot study documented that Melampyrum seeds are able to pass through the digestive tract of a cow intact.This suggests that large ruminants such as deer,bison or forest-grazing livestock may function as important long-distance dispersers of Melampyrum species.展开更多
In order to clarify the interactive mechanism between grazing yak and alpine meadow on the Qinghai-Tibetan Plateau,our study assessed seed density(by species)in the topsoil of alpine meadow with different grazing inte...In order to clarify the interactive mechanism between grazing yak and alpine meadow on the Qinghai-Tibetan Plateau,our study assessed seed density(by species)in the topsoil of alpine meadow with different grazing intensities in the Tianzhu area,north-eastern margins of the Qinghai-Tibetan Plateau and their rates of occurrence in yak dung.Seed density in the topsoil of the lightly grazed,moderately grazed,heavily grazed and extremely grazed alpine meadows in November,2010 were 1551,1692,2660 and 1830 grains m-2,while in the same meadows in April,2011 densities were 1530,2404,2530 and 2692 grains m-2,respectively.In the cold season pasture,mean seed density in yak dung from November to April in the lightly grazed,moderately grazed,heavily grazed and extremely grazed sites were 121,127,187,and 120 grains kg-1of dry yak dung.The proportion of total seed numbers in yak dung to soil seed bank in lightly grazed,moderately grazed,heavily grazed and extremely grazed alpine meadow was 1.40,2.62,0.69,and 0.90%.12 species out of the 47 were not found in topsoil but were found in yak dung,10 species out of 45 were not found in yak dung but were found in the topsoil.Endozoochorous dispersal by yaks is therefore very important for soil seed bank and plant biodiversity and population dynamics in alpine meadows.展开更多
Seed dispersal by exotic mammals exemplifies mutualistic interactions that can modify the habitat by facilitating the establishment of certain species. We examined the potential for endozoochoric dispersal of exotic p...Seed dispersal by exotic mammals exemplifies mutualistic interactions that can modify the habitat by facilitating the establishment of certain species. We examined the potential for endozoochoric dispersal of exotic plants by Callosciurus erythraeus introduced in the Pampas Region of Argentina. We identified and characterized entire and damaged seeds found in squirrel faeces and evaluated the germination capacity and viability of entire seeds in laboratory assays. We collected 120 samples of squirrel faeces that contained 883 pellets in seasonal surveys conducted between July 2011 and June 2012 at 3 study sites within the main invasion focus of C. erythraeus in Argentina. We found 226 entire seeds in 21% of the samples belonging to 4 species of exotic trees and shrubs. Germination in laboratory assays was recorded for Morus alba and Casuarina sp.; however, germination percentage and rate was higher for seeds obtained from the fruits than for seeds obtained from the faeces. The largest size of entire seeds found in the faeces was 4.2 ~ 4.0 ram, whereas the damaged seeds had at least 1 dimension ≥ 4.7 ram. Our results indi- cated that C. erythraeus can disperse viable seeds of at least 2 species of exotic trees. C. erythraeus predated seeds of other naturalized species in the region. The morphometric description suggested a restriction on the maximum size for the passage of entire seeds through the digestive tract of squirrels, which provides useful information to predict its role as a potential disperser or predator of other species in other invaded communities.展开更多
The current study focuses on the contribution of the dromedary in the preservation and increase of spontaneous flora through seeds transfer by endozoochory. Thus dromedary faeces have been collected in selected area o...The current study focuses on the contribution of the dromedary in the preservation and increase of spontaneous flora through seeds transfer by endozoochory. Thus dromedary faeces have been collected in selected area of region of Ghardaia （Northern Algeria Sahara）, since it is one of the three known cameline rangelands during the four successive seasons of the years 2009-2010, in order to examine their seed contents. Our investigation allowed us to invento 1,832 seeds representing 33 different types varying according to the seasons of harvest. The biggest density of seeds was present in summer with 986 seeds, against 424 seeds in winter, 366 seeds in fall and 56 seeds in spring, and of the same way, the biggest number of types was present in summer with 30 types, consistent of the fall season with 26 types, and arrived then the season of winter with 20 types and the one of spring with five types. The gotten results allowed us to appreciate the ecological role of this animal in the desertic ecosystem in the dissemination and the proliferation of the seeds of the spontaneous flora in its fragile and hostile desert environment to the survival of the seeds enveloped in its faeces.展开更多
Reproduction by perennial plants varies from being relatively constant over years to the production of massive and synchronous seed crops at irregular intervals,a reproductive strategy called mast seeding.The sources ...Reproduction by perennial plants varies from being relatively constant over years to the production of massive and synchronous seed crops at irregular intervals,a reproductive strategy called mast seeding.The sources of inter-specific differences in the extent of interannual variation in seed production are largely unknown.We conducted a global meta-analysis of animal-dispersed species to quantify how the interannual variability in seed crops pro-duced by plants can be explained by the seed mass,dispersal mode,phylogeny,and climate.Phylogenetic analysis indicated that the interannual variations in seed production and seed mass tended to be similar in related species due to their shared evolution.The interannual variation in seed production was 1.22 times higher in synzoochorous species dispersed by scatter-hoarders compared with endozoochorous species dispersed by frugivores.Further-more,the production of small seeds was associated with higher interannual variation in seed production,although synzoochorous species produced larger seeds than endozoochorous species.Precipitation rather than temperature had a significant positive effect on the interannual variation in seed production.The seed mass and dispersal mode contributed more to the interannual variation in seed production than phylogeny,climate,and fruit type.Ourfind-ings support a long-standing hypothesis that interspecific variation in the masting intensity is largely shaped by interactions between plants and animals.展开更多
Seed dispersal is essential for plant recruitment and the maintenance of biodiversity.Colobine monkeys are primarily folivorous,but they also consume fruits and are often assumed to be seed predators.Although they are...Seed dispersal is essential for plant recruitment and the maintenance of biodiversity.Colobine monkeys are primarily folivorous,but they also consume fruits and are often assumed to be seed predators.Although they are known to be epizoochorous seed dispersers,their role as endozoochorous seed dispersers needs reassessment.We examined potential endozoochory in golden snub-nosed monkeys(Rhinopithecus roxellana)at Dalongtan in Shennongjia National Park,central China,by assessing potential germination of ingested seeds(n=1806,9 species)from fecal samples.Intact seeds were in almost all fecal samples(ranging from 5-130 seeds),and ingested seeds were from small seeded species(seed width<4.5 mm).The 2 most abundant species were Actinidia arguta(73%)and Rosa caudata(15%).The fruits of A.arguta were unripe when ingested(i.e.effective seed predation)and the ingested seeds did not germinate in the trials.Therefore,ingestion of unripe seeds does not lead to effective seed dispersal.However,germination rates of defecated R.caudata(9%)were greater than control seeds(6%and 0%),demon-strating potential endozoochorous seed dispersal.Thus,colobine monkeys do indeed disperse mainly small-seeded from multi-seeded fruits through potential endozoochory and this process enhances the recruitment of seedlings.展开更多
The finding that some seed-inhabiting insects can survive passage through the entire digestive tract of seed-dispersing vertebrates is relatively recent,but evidence suggests that it does occur.Here,I document this ph...The finding that some seed-inhabiting insects can survive passage through the entire digestive tract of seed-dispersing vertebrates is relatively recent,but evidence suggests that it does occur.Here,I document this phenomenon,discuss its qualitative and quantitative dimensions,and offer suggestions for further research.The few documented cases that I review include plant species belonging to different families,with varied fleshy fruit types,number of seeds per fruit and seed size.The vertebrate frugivores involved include passerines that feed on relatively small fruits,and galliforms,and perissodactyls and primates that feed on larger fruits.The seed-inhabiting insects in-volved are the larvae of seed-infesting wasps,parasitoid wasps and seed-infesting beetles.The phenomenon has been verified in open,rural ecosystems in North America and Southern Europe,and in tropical and subtropical forests in South America.These varied scenarios suggest that the qualitative dimension of the phenomenon is considerably greater than known thus far.A simple method for detecting new events is proposed.However,re-search must also focus on the identity and biology of seed-feeding insects of wild fleshy fruits and their parasitoids.High survival rates of seed-inhabiting insects after vertebrate gut passage are predominant.This phenomenon generally appears to favor insect dispersal.展开更多
基金National Key Research and Development Program of China(2017YFC0503802)the National Natural Science Foundation of China(31770565 and 31270470)the Shanshuilintianhu Ecological Restoration Pre-Project of Jiyuan City,Henan.
文摘The plant-disperser-fruit pest triads involve 3 interacting animals or groups(plants,vertebrates and seed parasites),and the dispersal of both seeds and seed parasites,which can both benefit from endozoochory via defecation or regurgitation by frugivorous vertebrates.However,we have very limited knowledge about the ecological and evolutionary consequences of these plant-disperser-fruit pest triads.Across central Northern China,several seed wasps(mainly Eurytoma plotnikov attack Pistacia chinensis fruits,and seed wasp larvae can develop,diapause and finally emerge as adults inside a seed during the following 1-3 years.In this study,we experimentally investigated whether frugivorous birds discriminated P.chinesis fruits with or without seed parasites,and whether bird endozoochory(by defecation or regurgitation)affected larval survival of seed parasites.The infestation rate by seed parasites was 37%of the P.chinesis fruit crop but with up to 48%of aborted fruits.We found that all 5 bird species can discriminate and then reject all unhealthy fruits(including aborted and insect-infested).However,4 of the 5 bird species,in particular bulbul species,consumed 15-41%of aborted and insect-infested fruits as complementary food only when these unhealthy fruits were provided.Moreover,all larva of seed parasites remained alive after bird defecation or regurgitation.In conclusion,our study demonstrates that endozoochory by frugivorous birds could lead to potential dispersal of seed parasites of P.chinensis but with a very low probability.
基金Grant Agency of the University of South Bohemia(164/2010/P and 04-138/2010/P).
文摘Aims Melampyrum pratense and M.subalpinum are two myrmeco-chorous species,which possess similar habitat requirements and frequently occur together.Despite this,their population sizes differ markedly.Melampyrum pratense populations are usually very large,whereas M.subalpinum has rather small and isolated populations.We suggest that such an imbalance might be partially influenced by the difference in ant-mediated seed-removal rates.genus Melampyrum is considered to be exclusively myrme-cochorous,though to achieve the recent distribution of some Melampyrum species during the Holocene myrmecochory would be highly insufficient.We suggest that endozoochory takes place in the long-distance migration,whereas myrmecochory is important for the removal of seeds on a local scale.Methods For seed-preference analysis,M.pratense and M.subalpinum mixed seed samples were placed around Formica polyctena anthills.after a period of time,the remaining seeds of both species were counted for each sample.The results were analysed by analysis of variance and generalized linear mixed-effect model.To test myrmecochorous removal distances,M.pratense seeds were covered with fluorescent dactyloscopic powder and placed in the vicinity of a large ant trail.The area around the starting plot was searched in the dark using uV lED torchlight 7 h after the beginning.The distance from the starting plot was measured for each seed found.birds,rodents,leporine and a ruminant were fed with M.pratense seeds and fresh plants to test the possibility of endozoochorous dispersal of the species.animal droppings were searched for intact seeds.Important Findingsour field studies show that from mixed seed samples,containing both species,ants significantly preferred the seeds of M.pratense.This may be one of factors that has positive influence on M.prat-ense success in seed dispersal on mixed stands and consequently in the colonization of favourable sites.Experiments focusing on ant-mediated dispersal distance revealed that F.polyctena ants are able to move seeds over a distance of 36 m in only 7 h.This distance is among the furthest known myrmecochorous removals of forest plant seeds.a new Melampyrum seed disperser Oligolophus tridens(opiliones)was observed repeatedly.our pilot study documented that Melampyrum seeds are able to pass through the digestive tract of a cow intact.This suggests that large ruminants such as deer,bison or forest-grazing livestock may function as important long-distance dispersers of Melampyrum species.
基金supported by the National Natural Science Foundation of China(31001029)
文摘In order to clarify the interactive mechanism between grazing yak and alpine meadow on the Qinghai-Tibetan Plateau,our study assessed seed density(by species)in the topsoil of alpine meadow with different grazing intensities in the Tianzhu area,north-eastern margins of the Qinghai-Tibetan Plateau and their rates of occurrence in yak dung.Seed density in the topsoil of the lightly grazed,moderately grazed,heavily grazed and extremely grazed alpine meadows in November,2010 were 1551,1692,2660 and 1830 grains m-2,while in the same meadows in April,2011 densities were 1530,2404,2530 and 2692 grains m-2,respectively.In the cold season pasture,mean seed density in yak dung from November to April in the lightly grazed,moderately grazed,heavily grazed and extremely grazed sites were 121,127,187,and 120 grains kg-1of dry yak dung.The proportion of total seed numbers in yak dung to soil seed bank in lightly grazed,moderately grazed,heavily grazed and extremely grazed alpine meadow was 1.40,2.62,0.69,and 0.90%.12 species out of the 47 were not found in topsoil but were found in yak dung,10 species out of 45 were not found in yak dung but were found in the topsoil.Endozoochorous dispersal by yaks is therefore very important for soil seed bank and plant biodiversity and population dynamics in alpine meadows.
文摘Seed dispersal by exotic mammals exemplifies mutualistic interactions that can modify the habitat by facilitating the establishment of certain species. We examined the potential for endozoochoric dispersal of exotic plants by Callosciurus erythraeus introduced in the Pampas Region of Argentina. We identified and characterized entire and damaged seeds found in squirrel faeces and evaluated the germination capacity and viability of entire seeds in laboratory assays. We collected 120 samples of squirrel faeces that contained 883 pellets in seasonal surveys conducted between July 2011 and June 2012 at 3 study sites within the main invasion focus of C. erythraeus in Argentina. We found 226 entire seeds in 21% of the samples belonging to 4 species of exotic trees and shrubs. Germination in laboratory assays was recorded for Morus alba and Casuarina sp.; however, germination percentage and rate was higher for seeds obtained from the fruits than for seeds obtained from the faeces. The largest size of entire seeds found in the faeces was 4.2 ~ 4.0 ram, whereas the damaged seeds had at least 1 dimension ≥ 4.7 ram. Our results indi- cated that C. erythraeus can disperse viable seeds of at least 2 species of exotic trees. C. erythraeus predated seeds of other naturalized species in the region. The morphometric description suggested a restriction on the maximum size for the passage of entire seeds through the digestive tract of squirrels, which provides useful information to predict its role as a potential disperser or predator of other species in other invaded communities.
文摘The current study focuses on the contribution of the dromedary in the preservation and increase of spontaneous flora through seeds transfer by endozoochory. Thus dromedary faeces have been collected in selected area of region of Ghardaia （Northern Algeria Sahara）, since it is one of the three known cameline rangelands during the four successive seasons of the years 2009-2010, in order to examine their seed contents. Our investigation allowed us to invento 1,832 seeds representing 33 different types varying according to the seasons of harvest. The biggest density of seeds was present in summer with 986 seeds, against 424 seeds in winter, 366 seeds in fall and 56 seeds in spring, and of the same way, the biggest number of types was present in summer with 30 types, consistent of the fall season with 26 types, and arrived then the season of winter with 20 types and the one of spring with five types. The gotten results allowed us to appreciate the ecological role of this animal in the desertic ecosystem in the dissemination and the proliferation of the seeds of the spontaneous flora in its fragile and hostile desert environment to the survival of the seeds enveloped in its faeces.
基金supported by the National Science Foundation of China(NSFC)grant 32371609,the Excellent Youth Foundation of Henan Province grant 212300410050,and HASTIT grant 22HASTIT033M.Z.by the Natural Science Foundation of China(NSFC)grant 32201309+1 种基金Y.Y.by the National Science Foundation of China(NSFC)grant U2004150X.Y.by the National Science Foundation of China(NSFC)grant 32070447.
文摘Reproduction by perennial plants varies from being relatively constant over years to the production of massive and synchronous seed crops at irregular intervals,a reproductive strategy called mast seeding.The sources of inter-specific differences in the extent of interannual variation in seed production are largely unknown.We conducted a global meta-analysis of animal-dispersed species to quantify how the interannual variability in seed crops pro-duced by plants can be explained by the seed mass,dispersal mode,phylogeny,and climate.Phylogenetic analysis indicated that the interannual variations in seed production and seed mass tended to be similar in related species due to their shared evolution.The interannual variation in seed production was 1.22 times higher in synzoochorous species dispersed by scatter-hoarders compared with endozoochorous species dispersed by frugivores.Further-more,the production of small seeds was associated with higher interannual variation in seed production,although synzoochorous species produced larger seeds than endozoochorous species.Precipitation rather than temperature had a significant positive effect on the interannual variation in seed production.The seed mass and dispersal mode contributed more to the interannual variation in seed production than phylogeny,climate,and fruit type.Ourfind-ings support a long-standing hypothesis that interspecific variation in the masting intensity is largely shaped by interactions between plants and animals.
基金supported by the National Natural Science Foundation of China(31870509,31670397).
文摘Seed dispersal is essential for plant recruitment and the maintenance of biodiversity.Colobine monkeys are primarily folivorous,but they also consume fruits and are often assumed to be seed predators.Although they are known to be epizoochorous seed dispersers,their role as endozoochorous seed dispersers needs reassessment.We examined potential endozoochory in golden snub-nosed monkeys(Rhinopithecus roxellana)at Dalongtan in Shennongjia National Park,central China,by assessing potential germination of ingested seeds(n=1806,9 species)from fecal samples.Intact seeds were in almost all fecal samples(ranging from 5-130 seeds),and ingested seeds were from small seeded species(seed width<4.5 mm).The 2 most abundant species were Actinidia arguta(73%)and Rosa caudata(15%).The fruits of A.arguta were unripe when ingested(i.e.effective seed predation)and the ingested seeds did not germinate in the trials.Therefore,ingestion of unripe seeds does not lead to effective seed dispersal.However,germination rates of defecated R.caudata(9%)were greater than control seeds(6%and 0%),demon-strating potential endozoochorous seed dispersal.Thus,colobine monkeys do indeed disperse mainly small-seeded from multi-seeded fruits through potential endozoochory and this process enhances the recruitment of seedlings.
文摘The finding that some seed-inhabiting insects can survive passage through the entire digestive tract of seed-dispersing vertebrates is relatively recent,but evidence suggests that it does occur.Here,I document this phenomenon,discuss its qualitative and quantitative dimensions,and offer suggestions for further research.The few documented cases that I review include plant species belonging to different families,with varied fleshy fruit types,number of seeds per fruit and seed size.The vertebrate frugivores involved include passerines that feed on relatively small fruits,and galliforms,and perissodactyls and primates that feed on larger fruits.The seed-inhabiting insects in-volved are the larvae of seed-infesting wasps,parasitoid wasps and seed-infesting beetles.The phenomenon has been verified in open,rural ecosystems in North America and Southern Europe,and in tropical and subtropical forests in South America.These varied scenarios suggest that the qualitative dimension of the phenomenon is considerably greater than known thus far.A simple method for detecting new events is proposed.However,re-search must also focus on the identity and biology of seed-feeding insects of wild fleshy fruits and their parasitoids.High survival rates of seed-inhabiting insects after vertebrate gut passage are predominant.This phenomenon generally appears to favor insect dispersal.
