Group spawning, polyandry reproductive behaviors, and multiple paternity are increasingly reported in anuran species. The Omei treefrog （Rhacophorus omeimontis）, endemic to subtropical and mountainous forests of cen...Group spawning, polyandry reproductive behaviors, and multiple paternity are increasingly reported in anuran species. The Omei treefrog （Rhacophorus omeimontis）, endemic to subtropical and mountainous forests of central and southwestern China, is a polyandrous lek-patterned breeder commonly showing multiple males-one female matings during the breeding season. To detect the traits of social and genetic polyandry in this species and explore the relationships between these traits, we investigated the breeding behaviors of a population of R. omeimontis in the Fengtongzhai National Nature Reserve, Baoxing County, Sichuan, China. We conducted paternity analyses using six microsatellite genetic markers. A total of 30 matings were recorded in the field （four monogamous pairs and 26 spawning groups）. Our results revealed high proportions of social polyandry （86.7%） and multiple paternity （70.0%） and the numbers of joining males and genetic fathers among matings ranged from 1 to 8 and from 1 to 4, respectively. There was a significantly positive correlation between the intensities of social and genetic polyandry, indicating that multiple males-one female breeding behaviors could be an important promoter of multiple paternity. We considered the intense social polyandry and multiple paternity as consequences of intense male-male competition under a male-biased sex ratio and genetic benefits pursuing of the females. However, the proportion of genetic fathers in a spawning decreased with the increase of joining male number and most of their offspring belonged to a few males. This might be caused by a ＂making the best of a bad lot＂ reproductive strategy of the inferior male individuals.展开更多
Here we provide an example of simultaneous polyandry based on genetic evidence in Feirana kangxianensis. This stream-dwelling species occurs only in Kangxian County, southern Gansu Province, where it is sympatric with...Here we provide an example of simultaneous polyandry based on genetic evidence in Feirana kangxianensis. This stream-dwelling species occurs only in Kangxian County, southern Gansu Province, where it is sympatric with its sibling species E quadranus. During the breeding season the sex ratio of E kangxianensis was marginally female- biased （44~：59~） and the encounter rate in a relatively pristine habitat was significantly higher than that in heavily quarried habitats （9.6 ± 4.8 indiv./km vs. 3.2 ± 2.5 indiv./km）. Three egg masses containing an average of 698 eggs were deposited on the underside of one or two adjacent flat rocks, 6.0-10.0 cm under the water surface and 1.0-3.5 cm above the streambed. Using Bayesian sibship clustering of nine polymorphic microsatellite genotypes, two females were detected as group-spawning in one oviposition site, with three males fertilizing each female＇s eggs simultaneously. We also discuss the conservation requirements of this range-restricted species and the evolutionary implication of its unusual reproductive strategy.展开更多
基金supported by the National Natural Science Foundation of China(No.31470442)
文摘Group spawning, polyandry reproductive behaviors, and multiple paternity are increasingly reported in anuran species. The Omei treefrog （Rhacophorus omeimontis）, endemic to subtropical and mountainous forests of central and southwestern China, is a polyandrous lek-patterned breeder commonly showing multiple males-one female matings during the breeding season. To detect the traits of social and genetic polyandry in this species and explore the relationships between these traits, we investigated the breeding behaviors of a population of R. omeimontis in the Fengtongzhai National Nature Reserve, Baoxing County, Sichuan, China. We conducted paternity analyses using six microsatellite genetic markers. A total of 30 matings were recorded in the field （four monogamous pairs and 26 spawning groups）. Our results revealed high proportions of social polyandry （86.7%） and multiple paternity （70.0%） and the numbers of joining males and genetic fathers among matings ranged from 1 to 8 and from 1 to 4, respectively. There was a significantly positive correlation between the intensities of social and genetic polyandry, indicating that multiple males-one female breeding behaviors could be an important promoter of multiple paternity. We considered the intense social polyandry and multiple paternity as consequences of intense male-male competition under a male-biased sex ratio and genetic benefits pursuing of the females. However, the proportion of genetic fathers in a spawning decreased with the increase of joining male number and most of their offspring belonged to a few males. This might be caused by a ＂making the best of a bad lot＂ reproductive strategy of the inferior male individuals.
基金supported by the National Natural Science Foundation of China (31471964, 31200411)the Chinese Academy of Sciences (Y3C3011100)
文摘Here we provide an example of simultaneous polyandry based on genetic evidence in Feirana kangxianensis. This stream-dwelling species occurs only in Kangxian County, southern Gansu Province, where it is sympatric with its sibling species E quadranus. During the breeding season the sex ratio of E kangxianensis was marginally female- biased （44~：59~） and the encounter rate in a relatively pristine habitat was significantly higher than that in heavily quarried habitats （9.6 ± 4.8 indiv./km vs. 3.2 ± 2.5 indiv./km）. Three egg masses containing an average of 698 eggs were deposited on the underside of one or two adjacent flat rocks, 6.0-10.0 cm under the water surface and 1.0-3.5 cm above the streambed. Using Bayesian sibship clustering of nine polymorphic microsatellite genotypes, two females were detected as group-spawning in one oviposition site, with three males fertilizing each female＇s eggs simultaneously. We also discuss the conservation requirements of this range-restricted species and the evolutionary implication of its unusual reproductive strategy.
