It is very possible that plants have sensitivities that we do not yet understand. Because plants do not have nervous systems and cannot run away from predators, it has generally been assumed that they do not experience pain and suffering. Recent scientific evidence suggests that the life of plants is more complex than we once thought. However, we do know that birds, mammals and fish have well-developed nervous systems and pain receptors. Like us, they show pleasure and pain and they present comparable evidence of fear and well-being. Animals cry out in pain, they nurse wounded body parts, and they seek to avoid those who have hurt them in the past. In order to live, one has to eat. However, when we eat animal products, we consume many more plants indirectly than if we ate those plants directly, because the animals we eat are fed huge quantities of grasses, grains, and seeds to be converted into meat, milk, and eggs. As a vegan (one who eats no animal products) you cause fewer beings to suffer and die for you.