Art De Vany starts his Cell Competition and Cooperation, or Why Fat Cells Don’t Go Willingly with some examples of passive aggression in the wild:
Plants that are too easy to eat and are nutritious are attractive to herbivores. So, unless they can respond by limiting the ability of herbivores to digest them or by preventing the reproduction of herbivores, they will not survive the evolutionary race. Consequently, plants have many strategies to disarm, kill, or prevent the reproduction of their predators (herbivores). Grasses and the wheat that we eat that are evolved from them contain mineral sequestering substances that lock up the minerals in an herbivore, preventing mineral metabolism and growth. Phytic acid is one of the most prevalent of these and it binds zinc and calcium so that the herbivore does not develop. Phytic acid does the same thing in the human body so that a child raised on a high grain diet is deprived of the minerals he or she requires to develop. Rice, a relative of grass, does the same thing, which is one reason why northern Chinese are taller than southern Chinese; the northerners eat far less rice and more vegetables and meat.Another trick plants have to keep from being eaten is to chemically castrate male herbivores who consume them. The chemical in this case is a form of plant estrogen that de-masculinizes the male plant eater. This happens to human males too and to females who experience too much estrogen from eating soy beans and wheat.
Yet another trick is outright poison. Plant toxins are among the most dangerous in the biological world. Ricin, the deadly toxin that kills almost instantly, is derived from soy beans. Gluten, the deadly protein that dissolves the gut of celiac disease sufferers, is one of the other protective toxins that wheat and grass related plants use.
The same thing happens inside the body:
When it comes to cancer, strange things happen because cancer tumors compete with one another for the body’s resources. Large cancers secrete substances that limit the growth of smaller cancers. Thus, when a large tumor is removed surgically, the smaller ones are now left unsuppressed and may grow rapidly. This can present a problem for the patient. After a major cancer surgery the patient may face further cancers later because they are no longer suppressed by their larger competitors.
Then he moves on to fat — which is just another organ in the body, competing for resources.