A study has found that the males die due to increase in stress hormone levels and immune systems failure, News.com.au reported.
The team, which was lead by University of Queensland's Diana Fisher, concluded that this type of "suicide" is an adaptive response to intensified male sexual competition for females.
According to the study, female marsupials accumulate "fitness benefits" by timing peak energy demands of reproduction to coincide with maximum food abundance.
The study explains that in short mating cycles, the competition between males increase, and as they put more energy into copulating, their post-mating survival decrease.
The scientists said that among species with low post-mating male survival, those with suicidal reproduction have shorter mating seasons and larger testes relative to their body size.
Scientists insisted that this indicated a lethal effort of adaptivity in males as females escalate sperm competition by further shortening and synchronising the annual mating period and mating promiscuously.
The research is published in the journal PNAS.
--ANI (Posted on 08-10-2013)