Why is the Japanese quail (Coturnix japonica) such a good model for studying reproductive behaviour? The reason is that it offers numerous pratical advantages. First of all, it is very easy to manipulate in the laboratory and is significantly cheaper than a rat, for instance. Its physiology is also well known and quail have a very short reproductive cycle - sexual maturity is reached after six to seven weeks. Another advantage is that sexual differentiation takes place in the egg and not in the uterus, as is the case in the rats. Consequently, thanks to the techniques currently available, manipulations of the foetus are relatively simple, whereas they are more complicated in the rat and can possibly lead to abortion.

But that’s not all. The sexual behaviour of quail is essentially triggered by visual stimuli. In rats, the stimuli are mainly olfactory, and therefore a lot more difficult to control. Furthermore, contrary to its European equivalent (Coturnix coturnix), which only reproduces once a year, the Japanese quail displays a very active sexual behaviour that is present the whole year round, providing that subjects are maintained in lighting conditions similar to those of spring or summer (more than 12 hours of light a day).

There is a simple reason for this: quail were selected by industry to rapidly and continuously produce eggs and meat – this is the quail you find on menus in restaurants. The artificial selection to which it was subjected means that the female no longer incubates its eggs: it lays eggs on the ground and leaves. If Japanese quail were released into the wild, they would be incapable of reproducing.

According to Professor Jacques Balthazart from ULg's Center for Molecular and Cellular Neurobiology, the Japanese quail constitutes a simplified model for the control of sexual behaviour compared with the rat, and a fortiori man. In quail, this control greatly depends on the reptilian brain, rather than on cortical influences.

Thus, a male and a female that have been deprived of sexual partners for 24 hours, mate almost immediately, whereas rats would take ten to twenty minutes. These rodents pay more attention to the choice of a partner and to environmental factors.