Predator-Prey Relationships The relationship between predators and their prey is a complex and complex relationship; covering a vast area of ​​scientific knowledge. This article will examine the different relationships between predators and prey, focusing on the symbiotic relationships between organisms, the wide range of defense mechanisms used by various examples of prey, and the influence between predators and prey regarding evolution and structure. of the population. Symbiosis is the interaction between organisms forming a long-term relationship with each other. Many organisms become dependent on and need each other or one needs the other to survive. Symbiotic interactions include forms of parasitism, mutualism and commensalism. The first topic of discussion in symbiosis is parasitism. Parasitism occurs when the relationship between two animal populations becomes intimate and individuals from one population use the other population as a food source and can be located in or on the host animal or the animal of the other population ( Boughey 1973). No known organism escapes parasitism (Brum 1989). Parasitism is similar to predation in that the parasite feeds on the host it feeds on and the predator feeds on the prey it feeds on (Nitecki 1983). Parasitism is different from most normal predator situations because many different parasites can feed on a single host, but very few predators can feed on the same prey (1973). In parasite-host relationships, most often the parasite is smaller than the host. This would explain why many parasites can feed on a single host. Another difference in parasite-host relationships is that normally the parasite or a group of parasites does not kill the host by feeding, whereas a predator will kill its prey (1983). Effective parasites will not kill their host at least until their own life cycle is complete (1973). The ideal situation for a parasite is one in which the host animal can live long enough for the parasite to reproduce several times (Arms 1987). Parasites fall into two different categories depending on where they live on the host. Endoparasites are generally the smallest parasites and tend to live inside the host (1973). These internal parasites have certain physiological and anatomical adaptations to make their lives easier (1987). An example of this is the roundworm, which has a protective coating around its body to ensure that it will not be digested. Many internal parasites must have more than one host to reproduce (1989). A parasite can lay eggs inside the host in which it lives, and the eggs are excreted with the host's feces..