Is eating meat necessary?

Basic biology will tell you that within any given ecosystem you have plants, herbivores and carnivores (with an occasional omnivore). Plants will photosynthesis, taking light from the sun, and turning into nutrition, using it to grow, expand, pollenate etc. Herbivores in turn will eat the plants, using that nutrition to grow, expand, breed etc. Carnivores will then eat herbivores, using that nutrition to grow, expand, breed etc. But what happens when you remove all carnivores from any given ecosystem? The herbivore population explodes they eat all the plants and everyone starves. Eating meat is necessary to the preservation of any given ecosystem. Now many would argue that it's not necessary for people to eat meat. While that's technically true, population control is and has always been necessary. That population control can take the form of predators, killing and eating meat, or by controlled breeding, and by extension eating meat. Either way eating meat is and has always been necessary to the preservation of any given ecosystem.