Determine dysfunction. Let's take a look at another one. There was a called Bruce Effect. It's a very famous effect. What's Bruce Effect? Actually, it's this lady. That is actually in 1959, she noticed that pregnant mice will abort if they're exposed to another unfamiliar male. What's this mean? It's actually, if one mouse, actually female mouse already carried a baby, and then if there was a another intruder, went in to this colony by a male mouse, and then, there was a program actually built in the newer system. And then will trigger the abortion of these pregnant female mouse. This is called the Bruce Effect. And then, people found later actually that Bruce Effect actually is cost to buy the olfactory cues, his chemical cues. That means actually another intruder male carries some kind of a smell and chemicals, and then this female detected and then will go through the olfactory signaling, and then detect that signal, and will go to the brain, and then control that behavior. Is actually is controlled by the animal you serve. It's the female controls this behavior by herself. Later, people found actually also the Bruce Effect in the monkey. It's is a trove, a science paper. Over there they should be in the colony, in the monarchy of course it's a hierarchy, a dominant. [FOREIGN] The dominant male in this colony actually has all the power to mate with a female in the colony. And there is a observation if this male is weak and there was intruder, another male coming into this colony and the previously dominant male, actually, if you cannot win the fight with another male, then there was trouble. And that means actually he will give up this colony, and then the other one would take over. And when the other male monkey take over this colony, and all those pregnant female monkey will, how is it, abortion, okay? This is quite interesting. Why they needed to do this? It's not actually did a mayor force to do these thing. Again, those actually are behavior controlled by the female. Of course this one, he could argue that's because for this one they can save the energy to not waste any energies for breathing those kind of young baby from the previously father. Because actually you and those baby monkey grew up. And then, the new father will kill all those other young animals. So in this case, and you waste a lot of energy or resource from the female. Because you kind of maybe have a long time pregnancy and then the baby come out. And then, was killed by the new father. Then, it's just a waste. So in this case, as you do in the evolution, the monkey developed a program called Bruce Effect to control this fate by then served, by the female, by the mother. I forgot some quite while your touching behaviors, for example, for the elephant, if they found, actually, a dead one, they will stop there for quite a long time. And sometimes you can see the tears maybe come out. This is really called emotional goodbye. So what controls this kind of behavior? It's quite interesting, I just show a couple of these kind of behaviors and then we still don't know actually most of the genes and [INAUDIBLE] to control these kind of behavior. So talk about this one, then what's the behavior? What's the definition of the behavior?