Human beings are currently at the top of food chains, whether it is plant-based (for vegetarian diets) or meat based (for non-vegetarian diets). We should be concerned with the constraints faced by the organisms at the top of food chains. Since food chains show the direction of food and energy, we know that we are dependent on the organisms at the lower levels of the food chain and that we are constrained (in terms of food and energy) by the population of organisms at lower levels. Human population cannot be indefinitely supported by the limited number of plants and organisms at the lower levels of food chain. Ever increasing population is thus a risk. An equally bigger risk is the over-exploitation of organisms at the lower levels (deforestation, over-hunting, etc.), which will not leave enough organisms, at lower levels of the food chain, to support the human population. Thus, we need to be wary of our actions against the lower levels of the food chain, in order to ensure our continued survival.
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