As natural is a word with a vast definition, diet is one with almost unlimited scope. Hence, the exploration of a natural diet as the touchstone of optimal health is but a Grail quest.
The omnivorous diet of the San and Hadza interest us because modern hunter-gatherers are largely spared the common degenerative diseases afflicting West and East. They gather wild berries and nuts, hunt insects and small game, not the kind of fare that interests most of us, though nutritious. But do they represent a nutrition that molded our biology and genetics that we ought to imitate today?
Let’s look back in prehistory to when humans were evolving from apes, before they lived in degraded environments. We have lost an immensely rich megafauna that offered humans meaty meals. In a recent review, Tel Aviv researchers conclude that through most of the Stone Age we were apex predators and hypercarnivores (meaning >70% meat).
That we are flesh-eaters by nature (sic) can sound scandalous, implying we are not only responsible for the ongoing Sixth Extinction but a previous one in the Paleolithic era as well. Homo species probably carried as much responsibility for destroying biodiversity as climate change (perhaps more), causing mammoths, aurochs, saber-toothed tigers, cave bears, and other charismatic animals to vanish. I feel even more persuaded after my single experience of practical paleontology cleaning bones of a local Mastodon: our geologist, Jerre Johnson, declared it was killed by hunters.
The first hominids were primary vegetarians, like their ape antecedents. Before we emerged as a distinct species, our lineage was represented for a couple of million years by Homo erectus. By the Upper Paleolithic, a few tens of thousands of years ago, they helped to make large game scarce. We had to switch to a mixed diet of hunting and gathering, fishing and domesticating animals for meat and milk. The hunger for greater food security triggered the first Agricultural Revolution, and crop farming was so successful it created a population boom with social changes we still grapple with.
So, what is the evidence for carnivory? The authors reviewed 25 factors, including genetics and physiology, ecology and paleontology. Here are a few memorable examples, not just from gut and metabolism.
A highly acidic stomach adapted for killing bacteria in stale meat and carrion is absent in obligate plant eaters.
An adaptation for high fat consumption and insulin resistance
Micronutrients from animal sources (vitamin B-12 a top example)
Higher ratio of the length of small intestine to colon
Changes in masticatory apparatus and salivary enzyme genes for starch digestion
Endurance running and excess sweating for catching swift prey
Ability to throw weapons forcefully and accurately (chimps and gorillas can’t throw 100 mph fastballs)
Charles Darwin believed changes in diet shape evolution, famously illustrated by Galapagos finches. Maybe it’s hard for vegetarians and vegans to accept we are still adapted for a low-carb paleo diet, but our evolution creeps slowly because of long generation intervals. Eating mostly plants is no longer just a personal preference or from concern about animal welfare, but a virtue for lowering our impact on the environment. We never worried before about going against the grain by denying our nature of two feet on the ground when we wanted to launch into flight and space. Neither should we now.
In 1871, the now-extinct Hornet magazine published a cartoon of Charles Darwin looking like a human-ape chimera. It was not meant kindly.
We might suppose that progressive Victorian thinkers would have embraced chimps, gorillas, orangs, etc. as newly-found cousins. Perhaps some did, but lonely captivity in bare “prisons,” laboratory experimentation, and hunting continued.
It takes a long time for ingrained attitudes about the “beasts” to change, even when evidence mounts about their cognition and suffering. It’s ironic that medical research which adopted apes for human ends has raised appreciation of them as sentient beings that insists on a higher ethical standard of care not much different to what we demand for ourselves. Jane Goodall, the foremost chimpanzee expert and advocate, urges, “Surely we should treat them with the same consideration and kindness as we show to other humans; and as we recognize human rights, so too should we recognize the rights of the great apes?”
There was a recent instance of how attitudes are changing when the head of the NIH announced that the last 50 chimpanzees in federal laboratories will be retired to a sanctuary for the rest of their lives. The published reasons for freeing the chimps was utilitarian and couched in unemotional waffle (“the need for research has essentially shrunk to zero”), but I’m sure that public opinion influenced the policy. Pictures of apes in cages, separated from their babies, and communicating with people in sign language open our hearts to them as we see more of us in them and vice versa. We are unashamedly sentimental about our pets, and why not for our simian cousins too? This might sound surprising coming from a writer who sometimes used animals in research (never primates), but it’s not shameful to admit a change of heart. The treatment of animals as only subjects of curiosity, cuisine and companionship can evolve to something greater, although I can’t say how far the ineffable feelings can go.
The reason why animals, even apes, never deserved the protection of legal rights was, of course, because they are not human. They don’t have a brain and moral law that in our own estimation justified us as their emperors. The difference between Us and Them is that we regard ourselves as a benevolent species, for that’s what humane means. What a shocking self-deceit!
Most Victorians, irrespective of whether they believed the Creation Story or Evolutionary Theory, thought our species was destined to rule the Earth. The Darwinian revelation that we are a Johnny-come-lately species didn’t puncture that mental outlook, and modern ecology has struggled to fix a truer and more sustainable perspective against the resistance of economic and political forces. The justification for using and abusing animals was the same as that for the mistreatment and malice of other ethnicities of our own species—they were all dehumanized. Lately, I have been musing when the divorce with nature began.
A new breed of eco-theologians, including the late Thomas Berry, admit that the three great monotheistic religions unconsciously helped to vindicate brutal treatment of animals and careless stewardship of the environment. When people lived much closer to the land as a source of production, there could be greater feelings of unity with the rest of creation, and less hubris exploiting its “goods.” The natural world was a divine revelation that preceded the Scriptures. Still today, some native religions teach that the land and its inhabitants, plant and animal, are sacred, and the sacrifice of an animal taken in a hunt was a sacramental act for some North American Indians.
If I try to pinpoint a time and place in history when Western attitudes changed I choose Medieval Europe. As a devotee of Aristotle, Thomas Aquinas taught that humans stand at the apex of nature’s hierarchy, owing no special moral responsibility to animals, which are only instruments for our use. When the Black Death arrived a hundred years later, killing a third to a half of the population, the church tried to soften the horror of temporal existence and the hard Augustinian doctrine of a broken world by focusing the minds of the faithful on the permanent reward of peace in heaven. With eyes fixed on such a great hope why should anyone bother about the Earth and its creatures? Wasn’t the great lover of creation, Francis of Assisi, just a sentimental monk?
Although the tide of faith started ebbing in the Enlightenment, attitudes towards nature and animal life remained harsh. The wild woods, mountains, and oceans, and the creatures they harbored were dangerous, not precious gifts. Beauty and its ally, security, lay in the towns and cities, and urbanization increased the drift from old feelings of communion with nature. Materialism and its goods had arrived. Pressed to choose a historical figure to represent the changing secular attitudes it’s hard to beat Descartes. He drew a metaphysical gulf between Mind and Matter. Since animals were assumed not to have a mind or self-consciousness (now repudiated), they were regarded as biological machines, mere matter not calling for special care.
The promotion of a bunch of chimps to a gentler life as senior citizens is a tiny example of how public sensibilities have evolved, although there is a long way to go before deep-seated religious and secular assumptions are replaced with more open and enlightened feelings that can bring us closer to our spiritual Earth home. We can expect to see more controversy and struggles over our management of animals—for food production, sporting entertainment, medical research—and I have no idea where they will end. But a quotation from Henry Beston holds a guiding light for me. He was a friend of Rachel Carson and like another temporary hermit in Massachusetts, Henry David Thoreau, he spent a solitary year in a cabin, but beside the ocean instead of a pond. He wrote in The Outermost House:
We need another and a wiser and perhaps more mystical concept of animals. Remote from universal nature, and living by complicated artifice, man in civilization surveys the creature through the glass of his knowledge and sees thereby a feather magnified and the whole image in distortion. We patronize them for their incompleteness, for the tragic fate of having taken form so far below ourselves. And therein we err, and greatly err. For the animal world shall not be measured by man. In a world older and more complete than ours they move finished and complete, gifted with senses we have lost or never attained, living by voices we shall never hear. They are not brethren, they are not underlings; they are other nations, caught with ourselves in the net of life and time, fellow prisoners of the splendor and travail of the earth.
I guess old Darwin would have shared those feelings and welcomed the belated rediscovery we are making of caring for our real home, this shrinking world with its creatures whose destiny is more completely in our hands than ever. He might have enjoyed seeing his caricature in magazines, believed there was dignity in a hairy pelt, and reflected on Francis’s dream of an Earth family—Mother Earth, Brother Wind and Air, Sister Water, Brother Donkey, Brother Chimp, Brother Darwin.
Does any vocation have a more open and welcoming door than natural history? To be a naturalist, you don’t need a high school diploma or a university degree; there is neither an age barrier nor a physical fitness test. Plenty of societies exist for fostering interest, but membership is optional because it is okay to belong to your own club of one. It helps to have keen senses and a memory for identifying species, but curiosity and passion about nature are the defining characters of a naturalist. No higher qualifications are required.
“There’s a bunch of naturalists,” someone exclaims at the sight of one straining through binoculars for a bird or flipping through a field guide to identify a plant or butterfly. But they can be recognized in countless other ways and places too. Some volunteer for conservation work, some express their love of nature through art or photography, some compose essays or poetry to celebrate it, while others choose the simple joy of a country walk. Everyone is welcome at nature’s table.
It’s a mystery why this passion germinates in some people but not in everyone. Nature casts its spell over the human psyche at every age, but in childhood it is often nurtured by parents, friends and teachers, and nourished by visits to wildlife parks and the spectacle of museum dioramas. Summer camps may bring it to full bloom in adolescence, but what next? There are jobs for naturalists as conservation officers and rangers, but for most of us it is a lifelong hobby, and there’s the rub.
In an age that prizes academic qualifications and technical know-how, natural history is often regarded as little more than a casual pastime. It deserves greater honor. All the early naturalists were amateurs, but many of them plowed personal wealth into their endeavors, and sometimes took great risks. Naturalists like Alfred Wallace was famous for trotting around the globe describing, collecting, and illustrating specimens; others like Charles Darwin never ventured further than his home turf after disembarking from the Beagle, yet he laid the foundations of modern biology and geology. Some of the greatest minds in history starting with Aristotle were naturalists, and the scientific disciplines most closely-related to natural history today—ecology and evolution—are intellectually rigorous. Aristotle has been called the first naturalist and the first biologist, but are those labels interchangeable? Not exactly.
Naturalist was coined around 1587 whereas the closely-linked words, biologist and scientist, were Victorian inventions. This vintage word is sometimes muddled with metaphysical naturalist (someone who holds a materialistic philosophy), or with naturist (nudist) when someone goofs in a spelling bee!
There is more confusion because of the broad dictionary definition: “the study of living and non-living things, and of how plants and animals are adapted to their environment.” A list of American naturalists expanded the meaning even wider by including the astronomer Carl Sagan, perhaps because he speculated about “little green men” in other worlds! So much diffusion of meaning usually diminishes the value of a word, but I argue the opposite.
The contributions of amateurs to ecology, geology, and astronomy are more important now than ever before. Unlike heroes in fashionable biomedicine who have deep pockets for research and can win Nobel Prizes, amateur naturalists go uncelebrated as they step forward for voluntary conservation work with the satisfaction of “making things good” as their only reward. Last month, our local chapter of the Virginia Master Naturalist program celebrated the graduation of 23 new members. There are 28 other chapters in the State and similar programs nationwide that are growing rapidly. It is quite inspiring to watch these naturalists quietly giving their time and sharing expertise as they survey wildlife, improve habitats, and monitor weather patterns. These unpaid services help to improve the biological quality of nature parks and waterways and make huge contributions to knowledge in an era of environmental stress.
Amateur naturalists and professional biologists look like natural twins to outsiders because they have so much in common. But like twins, they occasionally fall out. The Romantic Poets who idealized nature were early critics of science before the Industrial Age got underway and before the storms over animal vivisection and so much more to come.
Naturalists who regard their role as defenders of the planet can turn scornfully on developments that threaten biodiversity, spread pollution, and release genetically modified organisms. Activists have launched hundreds of environmental organizations—the Ocean Conservancy, Greenpeace, Rainforest Action Network, Sierra Club, and the R.S.P.B. to name a few. Those who straddle as biologists by profession and naturalists by vocation feel uncomfortably dissected, like chimeras with two talking heads. This is not a clash between sentimental naturalism and hard-headed science, but about values and attitudes. Care, respect, even love, characterize the naturalist, whereas honesty, patience and caution are watchwords for the professional biologist.
Wordsworth’s poetry contains faint echoes of pagan deference to nature, but it also nods towards the New Age movement that emerged more recently. There have always been people for whom nature is spiritually refreshing, and some found joy in it when the rest of their world looked desperately bleak.
“The two of us looked out at the blue sky, the bare chestnut tree glistening with dew, the seagulls and other birds glinting with silver as they swooped through the air, and we were so moved and entranced that we couldn’t speak.” Ann Frank writing from a secret annex, February 23, 1944
Since mainstream religions always claimed to be guardians of spirituality and morality leaders, I wonder where they were in the debate about care of the environment. They were stuck in medieval theology for a long time.
When Darwin enrolled in Cambridge University, his intention (at least his father’s) was to enter the priesthood where there were many parson-naturalists. The Church of England offered a comfortable living for gentlemen, and enough spare time to pursue nature studies. Charles’ circumstances changed so he could pursue his first love full-time, but what were the attitudes of his contemporaries who took up holy orders? They rarely used the pulpit to preach stewardship of the creation, nor would Charles had he donned a cassock and surplice because apocalyptic visions of environmental collapse would have sounded bizarre even to ardent naturalists before the 20th Century. The long struggle of civilization to tame wild nature and meet human needs and wants was not yet over. Nature was scary. Besides, both Saints Paul and Augustine had elevated the doctrine of Original Sin to the center of theology, and the whole environment was caught up in this theological “corruption.” Much less attention was paid to the God of Genesis I, who expressed joy in his creation which was “verygood.”
So many years later when Rachel Carson’s Silent Spring (1962) was published and a Green Movement was sprouting, there were young naturalists sitting in the same church pews who wondered if the church had at last a change of heart. It hadn’t. The clergy found so much more biblical exegesis for instructing us on the care of our fellow humans that it forgot to say anything about caring for the natural systems that support us. Perhaps the Commandment Thou shalt not steal comes closest to an environmental ethic, if it is construed as a call to responsibility for the sake of future generations.
As nature and church were dear, I found the clerical vacuity embarrassing and alienating. My frustration exploded in 1989 when I published “What on Earth does the Kirk think about Ecology?” in the Church of Scotland magazine Life and Work. Of course, a layman cannot stir up the church hierarchy, but there was a consolation when invitations to speak at the Women’s Guild meetings rolled in.
There has been dramatic greening of churches since those days, and thoughtful books from writers representing all the Abrahamic religions. This late flurry looks like a rearguard action to critics who suspect that churches are struggling to gain authority on a vital topic, but the new focus is nonetheless welcome. There is even a “Green Patriarch” heading the Orthodox Church, and an encyclical about climate change is anticipated from the Vatican where Pope Francis has already brought fresh attention to the subject.
“The vocation of being a “protector”, however, is not just something involving us Christians alone; it also has a prior dimension which is simply human, involving everyone. It means protecting all creation, the beauty of the created world, as the Book of Genesis tells us and as Saint Francis of Assisi showed us. It means respecting each of God’s creatures and respecting the environment in which we live.” March 19, 2013.
Judging by action and behavior, most of the public is deaf to calls from governments, scientists and activists to live more carefully with nature. A Canadian environmental psychologist, Robert Gifford, calls our excuses the “Dragons of Inaction,” which include: “I’m only one, so my effort is a drop in a bucket/ Why should I bother when richer folk don’t/ I’m tired of the publicity/ I’m too busy in my job…” and twenty-seven other excuses where the pronoun “I” is dominating.
There is plenty of speculation about the future legacy of Pope Francis, but his call to be “protectors” of the earth could be the greatest. It is an appeal to people who have faith and others who have none, to those who are heads of state and industry and others who are powerless. Its scope is global because we face an uncertain future together, although the rich world still insulates itself from disasters that affect others, such as rising sea levels forcing emigration from oceanic islands, depletion of fishery stocks, crop failures, drought and desertification.
We have low expectations of progress or agreement between nations because of the drag of vested interests. When science, our best hope, fails to persuade or is befouled in politics what hope, what straws, are left? Perhaps only spiritual ones.
I hope the Pope will remind us of collective guilt for generations of aggressive handling of this wonderful heritage. If shaming is the first lesson, the second must be preaching the stewardship of care. He needs to inspire spiritual zeal that breaks through the old cynicism and the apologies of the Dragons of Inaction to a vision of a world order that is kinder to the environment, more just to the powerless, and considerate of human needs not only in his flock, but all.
The early church fathers had a Greek word, koinonia, which roughly translated means “communion.” They had in mind a fellowship of believers, but it is an apt expression for the “protectors” who Pope Francis is calling for. There is something deeply spiritual in this idea. At the beginning of this post, I defined the word naturalist in a broad way, not restricting it to a clique of birders or voluntary conservationists, but embracing everyone who loves nature, even if they live their whole lives in the city. My definition includes the ladies I met in the Women’s Guild though they never strung binoculars round their necks, and Ann Frank who never hugged her chestnut tree. Everyone who cares about nature has the heart of a naturalist, because they share a passion for the earth.