| Abstract: | 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. |
