All entries for Saturday 25 March 2006
March 25, 2006
The Sex Life of The Ladybirds: Meeting, Courting, Mating
Follow-up to The Sex Life of the Ladybirds: Introduction from Reverie
Certain breeds of ladybirds bear clear gender distinctions (e.g. with a Siberian, the individuals with black head are male and the ones with a white head with a black spot are female). However, ladybirds inhabiting European lands are somewhat uniform and bear little sexual characteristic features, thus it can be impossible to tell the sex of an individual ladybird. For a human to satisfy his/her curiosity, one has to execute the ladybird and perform an autopsy, or wait till the mating process begins to witness the male ladybird adopt a certain specific position, climbing on top of the female one, to be able to say “it’s a boy! It’s a boy!”
If one isolates the male from the female for a couple of days and then puts them back together on a Petri dish, the mating process may commence in a couple of seconds. The process of identification of the partner happens momentarily. If the female is an experienced one and not a timid virgin, then the courting won’t take long either. When a mature male and a fresh virgin female ladybird are brought together, one can witness some genuinely soulful scenes of seduction, pursuit, struggle and finally deflower-ment of the virgin ladybird.
Below we shall describe the process in greater details using the example of the most common European breed of ladybirds – the Adalia bipunctata with two spots on their backs.
When a male Adalia meets another representative of the same species he inevitably makes a full-hearted attempt to climb on top of the other one. If he later discovers that he has mounted another male he will retreat immediately. But if he was lucky to have met a female he will make an effort to copulate with her.
During the process of mating the female does not actively engage in food hunting, although if offered food, she wouldn’t refuse either. The male Adalia usually remains still during copulation. However with bigger breeds of ladybirds, for example the septi-spotted (seven spots on the back) ladybirds, the male is capable of showing some exceptional temper and passion, rocking bluntly from side to side from time to time. Such scenes of passion are not recommended for small children to observe.
Adalias are perhaps the only species on earth whose male individuals are capable of ejaculating on average 2–3 times per copulation. Adalias like to take their time when it comes to love making. Like other breeds of ladybirds, Adalias can engage in a love-making session for one to up to 8 or 9 hours. In favourable circumstances Adalias can copulate every day and possibly even for a multitude of times during the same day.
One may ask about the point of such prolonged copulation sessions. It seems apparent that extensive copulation, during which the male don’t eat, both individuals don’t move much and are open for attacks are obviously destructive for the breed. Then how come evolution has helped extend their mating sessions for so long? There’s only one answer available at the moment: it is beneficial for the male. While fornicating a female the male individual naturally obstructs other males from engaging in the same business and thus boosts the possibility of passing own his own genes to the offspring. Mammals are known to keep to the tactic of active protection and prevention – they fight off any competitor claiming the same female. Ladybirds are much more of gentlemen – they choose the passive tactic by simply sitting on the females for hours without withdrawing the contact with the female, naturally depriving other males of the bare possibility to copulate with the same female.
The sperm produced with each copulation is enough to fertilize about 550 eggs. On average a female lays 15–20 (maximum of 40) eggs, preserving the rest of semen for about a month. With multiple partners a female is capable of laying up to 1000 eggs per season. If one partner’s sperm can do the job of fertilizing a great number of eggs, then what is the point of repeated copulation with different partners? Again, the benefit for the male is obvious: he gets to materialize his desire to produce as many offspring as possible carrying his genes. The female interest in this business is rather obscure, but can also be explained with the desire to spread one’s genes in a greater multitude of combinations.