Group living has increasingly been emphasized due to its potential consequence on inbreeding, nevertheless, the relationship between group living and inbreeding risk is largely unknown. The endangered snake species, S...Group living has increasingly been emphasized due to its potential consequence on inbreeding, nevertheless, the relationship between group living and inbreeding risk is largely unknown. The endangered snake species, Shedao pit viper(Gloydius shedaoensis) inhabiting mostly on Shedao Island(meaning "snake island" in Chinese), provides an excellent model system for research on group living and inbreeding risk. Small island area, high population density and extreme seasonal foraging opportunity prompt many individuals to live on the same tree, which likely increase the potential mating among relatives. To confirm this probability, we used genotypes from 13 microsatellites DNA markers and examined the genetic relationships between pair of individuals lived on the same tree. The results showed that snakes on the same tree did not show closer relationships compared with individuals from different trees. The group constructions based on scenarios of parental-offspring, full-sibling, half-sibling as well as cousin were not consistent with tree-based group living. In addition, we did not find significant correlation between pair of individual genetic distance and geographic distance going beyond trees, suggesting group living on trees might not elevate inbreeding risk.展开更多
Group living reduces the chances of predation.This is also true for burrowing animals,which use burrows as refuges to escape predators.Living in the center of a colony is the safest because it offers access to the gre...Group living reduces the chances of predation.This is also true for burrowing animals,which use burrows as refuges to escape predators.Living in the center of a colony is the safest because it offers access to the greatest number of burrows;however,it is stressful due to frequent aggressive interactions there.We predicted that larger and older animals should occupy areas of a colony with a higher density of burrows than smaller and younger ones.To test this prediction,we observed individually marked Qinghai toad-headed agamas(Phynocephalus vlangalii)from a single colony late in the breeding season when females were gravid.Density of burrows was the highest and distance between them the shortest in the center of the colony.Aggressive encounters were more frequent in the central part of the colony than on its periphery.We found a negative correlation between body size and distance to the center of the colony for females,but not for males.There was no such correlation between age of individuals and distance to the center of the colony.Females in this species likely compete with other females and males for central burrows in the colony even after mating season finishes.We suggest that gravid females likely compete for the dense burrows within the central part of the colony mainly due to their relatively lower sprint speed and higher probability of being caught by a predator if they are not refuged in a burrow.展开更多
基金supported by grants from Liaoning Snake Island Laotie Mountain National Nature Reserve (grant number: Y8Y3041)Biodiversity Survey and Assessment Project of the Ministry of Ecology a nd Environment (gra nt number: 2019HJ2096001006)。
文摘Group living has increasingly been emphasized due to its potential consequence on inbreeding, nevertheless, the relationship between group living and inbreeding risk is largely unknown. The endangered snake species, Shedao pit viper(Gloydius shedaoensis) inhabiting mostly on Shedao Island(meaning "snake island" in Chinese), provides an excellent model system for research on group living and inbreeding risk. Small island area, high population density and extreme seasonal foraging opportunity prompt many individuals to live on the same tree, which likely increase the potential mating among relatives. To confirm this probability, we used genotypes from 13 microsatellites DNA markers and examined the genetic relationships between pair of individuals lived on the same tree. The results showed that snakes on the same tree did not show closer relationships compared with individuals from different trees. The group constructions based on scenarios of parental-offspring, full-sibling, half-sibling as well as cousin were not consistent with tree-based group living. In addition, we did not find significant correlation between pair of individual genetic distance and geographic distance going beyond trees, suggesting group living on trees might not elevate inbreeding risk.
基金The field expenses were covered by the National Natural Science Foundation of China(32270527,31872233)Yin QI.The laboratory work was supported by the Russian Science Foundation RSF 22-14-00227+1 种基金The present work is a part of the long-term field study of P.vlangalii and the permits for it were obtained from the Zoige National Wetland Nature Reserve and local conservation authorities.Animal handling follows approved protocols(number 2018016,Animal Ethics Committee of Chengdu Institute of Biology)We adhered to the ABS/ASAB“Guidelines for the treatment of animals in behavioral research and teaching”.
文摘Group living reduces the chances of predation.This is also true for burrowing animals,which use burrows as refuges to escape predators.Living in the center of a colony is the safest because it offers access to the greatest number of burrows;however,it is stressful due to frequent aggressive interactions there.We predicted that larger and older animals should occupy areas of a colony with a higher density of burrows than smaller and younger ones.To test this prediction,we observed individually marked Qinghai toad-headed agamas(Phynocephalus vlangalii)from a single colony late in the breeding season when females were gravid.Density of burrows was the highest and distance between them the shortest in the center of the colony.Aggressive encounters were more frequent in the central part of the colony than on its periphery.We found a negative correlation between body size and distance to the center of the colony for females,but not for males.There was no such correlation between age of individuals and distance to the center of the colony.Females in this species likely compete with other females and males for central burrows in the colony even after mating season finishes.We suggest that gravid females likely compete for the dense burrows within the central part of the colony mainly due to their relatively lower sprint speed and higher probability of being caught by a predator if they are not refuged in a burrow.
