Well, doesn't it depend on how harsh the environment is? For example, if there's not enough food for the population then only those most capable of acquiring f

Well, doesn't it depend on how harsh the environment is? For example, if there's not enough food for the population then only those most capable of acquiring food will survive. But today, where we have great plenty (in some parts of the world) and advanced medical care etc, what you said is certainly true.