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When talking with people about the physical differences between carnivores and humans it has come up that we have the physical characteristics of both carnivores and herbivores and therefore were meant to eat meat. Even though we have more characteristics of herbivores, it is assumed that since we have a few carnivorous attributes it follows that meat should be included in out diet. How would you tackle this? I have quoted the following differences:

• We do not have a hinged jaw for ripping apart flesh but one that is able to grind sideways.
• We have a longer digestive system so we are better able to get the nutrients from our foods as opposed to the shorter tract that carnivores have to enable them to pass the meat through their body before it becomes rancid.
• It has been put forward that we have incisors for tearing flesh, but I have always thought that these were for cropping the harder vegetables.
• We do not have claws or talons for tearing flesh.
• The enzymes in our saliva that start breaking down the food in our mouths and the early part of our digestive tract are of a low acidity level and in alignment with a plant based diet.

I would greatly appreciate any ideas or thoughts that you may have on this subject.

There has been much dissension among scientists regarding the topic of human physiology and diet, and opinions have spanned the continuum from one end to the other. The fact is, human physiology does not fit neatly into any of the three major categories of mammalian diets: carnivorous, herbivorous, or omnivorous. We have a few traits from each of these classifications, which makes it easy for researchers to "prove" their position merely by pointing out those characteristics that suit their particular opinion.

It is often suggested that specific features of human anatomy or physiology dictate our behavior. However, from the perspective of diet, our physical makeup only prescribes our nutritional requirements, not how specific nutrients must be obtained. For instance, although we have a nutritional need for iron, there are many dietary sources of iron. Nutritionally speaking, it is irrelevant whether we get our iron from plant or animal sources; what matters is simply that we get it.

The argument that "biology is destiny" is typically used to justify a particular eating style. In that light, we must acknowledge that humans are the only species on Earth that appears to have no idea what its ideal diet should be. We are also the only species that has self-inflicted diet-related diseases, caused extensive environmental destruction through basic food production, and created pathogenic infestations that widely infect our food supply.

This type of reasoning also blatantly ignores a critical element of human evolution -- the aspect of choice. The arguments that "humans are meant to eat meat" or " humans have always eaten meat" are certainly no rational defenses for its continuation. If we were to accept this type of twisted logic, we would also have to say that humans have always murdered, raped, enslaved, and committed other heinous acts that our culture today finds reprehensible. Unlike most other animals, humans can choose what foods to eat. Sadly, our poor choices in the past have ravaged our land; fouled our air and waterways; heaped immeasurable suffering upon other species; and undermined our own health.

Our ability to digest a wide variety of foods undoubtedly contributed to our species' survival throughout history. Today, however, our dietary choices have more to do with tradition, culture, economics, politics, and availability than with some predetermined fate. It is time for our species to behave responsibly and select those foods that best sustain the Earth, the animals, and ourselves. Only then can we truly say we that humans have evolved in body, spirit, and wisdom.