?Scientists at the Monash University have discovered that the production of male sperm may be more difficult for the male than previously thought. The conclusion was reached during research which involved the use of the Australian cricket known as Teleogryllus oceanicus. Male crickets were placed with three types of female crickets: sexually immature, sexually mature/capable and sexually incapable females. During the trial, the male's sperm quality was checked twice and the male's immune function once.

Damian Dowling of Monash University’s School of Biological Sciences states, "This study challenges the traditional view that sex, and sperm production, come cheaply to males. It is typically thought that females must invest heavily into reproduction, whereas males can freely produce millions of high-quality, tiny sperm on demand, with few costs.”

The male crickets who were placed with sexually mature/capable females were able to produce high-quality sperm when they engaged sexually with the females, unlike the males housed with the sexually immature and sexually incapable females. The male cricket's quality sperm production also appeared to have a negative effect on the male's immune system. The negative effect on the immune system is believed to be caused from the male's body investing more energy into its sperm production and less into its immune system. The lowered immune system made the quality sperm producing male cricket more susceptible to bacterial infections.

The scientists at Monash University concluded that the added energy the male invests in high-quality sperm production may lead to health problems in males because of his lowered immune system.