 Inter-specific interaction, the predation, first the contents, definition of predation, then the predator-pre-population interaction, and the predistribution, effect of predation and the prey distribution. So, first the predation. So, predation is actually the phenomena or the interaction between two animals in which one animal kills other animals and uses its flesh or eats the second animal. So, in such an interaction, one animal interacts with another animal in such a way that the first animal kills the second animal and uses the second animal as food. It uses the food as a death cause. So, if we look at it normally, the animal which is killing the second animal, the animal which is killing the second animal, that is called the predator. And the animal being killed, that is called the prey. The animal being killed is the prey and the killer is actually the predator. The predation is different from parasitism. In parasitism, one animal does not become the victim of the second animal's death. So, it uses the food as a rule, but it does not use its death cause. So, in predation, the food is obtained by killing the other animal. So, what is the effect of predator-prey interaction? If we look at predator-prey interaction in natural environment, it is a very complex interaction. So, predator-prey interaction is very complex in nature. So, if there is a natural environment, if there is a large population of prey, then ultimately this large population of prey can support large population of predators. So, if the prey's population is large, then ultimately this environment can have a lot of predators in it. So, as a result, if there is a large population of prey, then ultimately there is a large population of predators. So, if the population of prey decreases, if the population of prey decreases, the population of the predator will also decrease. So, if the prey's population decreases, then the prey's population will also decrease. So, it means more prey, more predators, less prey, less predators. So, predator and prey's population tell each other that they are mutually controlled or coordinated. So, the predation or the predator, they also control the distribution of prey. So, if the predator is controlling the prey's population, or if the prey's population is large, then the predator will increase and ultimately control the prey. The second one, the important thing is the prey distribution. So, predation, the predator also controls the distribution of the prey. So, what will happen if the prey is in these areas? So, it is a forest. If there is a deer in the forest, then if it starts wandering in open areas, then the predator will easily catch it. So, it is always on safe places. So, the distribution of prey in the safe areas, it will not bring it to you in open areas. The next example is the example of trout. These trout are the trout of the Northlake. It is said that if we study its distribution, then in the Northlake, the North America Lake, the large lakes in Canada, the trout of these great lakes will never enter the fresh waters of Siberia after moving these trout. This means that the water is present. But despite that, it will never enter the fresh waters of Siberia after moving the trout from the Northlake. The reason for that is the lemperies. Predator lemperies are present in the Siberian fresh waters. That is why they never move. And this specific type of trout is present only in the waters of the Northlake or in the water of the North America.