Because insects are mostly very small and adaptable, they can occupy a great many ecological niches. Various insects and stages of insects feed on roots and parts of roots, fungi in the soil, buds, plant stems, flowers, fruits, the upper and lower sides of leaves, and on other insects that feed on leaves, roots, flowers, and stems. In the immortal words of Jonathan Swift, in his “On Poetry: A Rhapsody” (which is actually long on parody and short on rhapsody):
So, naturalists observe, a flea
Has smaller fleas that on him prey;
And these have smaller still to bite ’em,
And so proceed ad infinitum.
Consider the Hymenoptera, for instance, which have played essential roles in the evolution of entomophagy and will surely be critical partners in any sustainable future. Xyelid sawflies evolved in the Triassic treetops a couple of hundred million years ago; they mostly ate pollen, buds, or leaves, but became the ancestors of millions of species of bees, ants, and wasps, including the fairy wasps sometimes referred to by their more endearing name of fairyflies (Mymaridae). There are 1,400 known species of these tiny (less than a millimeter in length) wasps. They are parasitoids, meaning that they eat other insects. Like many parasitic wasps, fairy wasps are important predators of plant-feeding insects — a natural and essential form of insect population control, which is important if we are serious about entomophagy. I shall come back to this later, but for now we are just looking at numbers. Fairyfly eggs are inserted by their moms into the eggs of other insects, which provide a fresh food source once they hatch. If you are very, very tiny, the world offers so many options for housing and food! There are also parasitoids of parasitoids, and parasitoids of those, all of which represent the converse of the old saw about a revolution devouring its children. In this case, the insect revolution’s children devour their evolutionary parents. Euceros species, for instance, are hyperparasitoids of the larger Ichneumonidae (more than eighty thousand species) wasp family; the larvae are deposited on leaves, and attach themselves to passing sawflies, wait for a primary parasitoid to emerge from the sawfly, and then move into it and eat it.
Another contributor to the overwhelming insect population numbers is that, most annoyingly to larger predators, many of them learned how to fly early in evolutionary history, seeking out new places to breed and new sources of food. One of my most vivid memories from summer camp on the shores of Lake Winnipeg is the day when huge swarms of what we called fishflies, but were more accurately mayflies, lifted from the water in a cloud of biblical proportions (which was Christian summer-camp language for “big”) and coated all the cabins, trees, shrubs, paths, and campers. What our counselors never told us was that the amazing, exuberantly flittering cloud of bugs was in fact an orgy, the long-legged males transferring spermatophores to their dancing virgin female partners, who then dropped back to the lake, where they dumped their fertilized eggs into the water before a fish or bird could eat them. Oh, had we only known! What lusty adolescent tales we could have imagined! Not believing in evolution, our counselors also never informed us that mayflies are among the most ancient of fliers, having first taken wing more than 300 million years ago. For 150 million years, insects were the only animals to fly.
More than 200 million years ago, insects invented (well, evolved) complete metamorphosis, in which an animal goes through several distinct and very different stages — think caterpillars, pupae, butterflies. For one thing, this means that the immature stages (larvae) don’t look at all like the adults (moths), a problem which we have already identified for naming edible bugs. Ecologically, complete metamorphosis has other implications, perhaps the most important being that larvae don’t compete with adults for the same food sources. In fact, sometimes adults don’t eat anything at all. More than 75 percent of all extant insect species undergo complete metamorphosis. For entomophagists, complete metamorphosis provides a more diverse palate of possible options, but for those concerned with foods other than insects, this multiplicity of forms is more problematic.
Grape phylloxera (Daktulosphaira vitifoliae) is an aphid that nearly destroyed the French wine industry in the nineteenth century and continues to generate consternation and anxiety among vintners and oenophiles the world over. Phylloxera are members of the Hemiptera (true bugs). They are said to have somewhere up to eighteen forms, according to a classification based on sexual and dietary habits as well as whether or not they have wings. We could start anywhere in the reproductively clever tangle of their lives, but let’s start with what one would think is the most straightforward distinction: males and females. Phylloxera are born without digestive systems from eggs laid on the underside of grape leaves, and then proceed to do what any energetic stomach-less males and females would do: they mate. Then they die, but not before the female lays one egg on the trunk of the vine. The egg eventually hatches into a nymph, who then clambers up onto a leaf, creates a gall by injecting her saliva, and then lays eggs in the gall without having had the fun of mating. In any case, the next generation of nymphs may travel to other leaves, or down the stems to the roots, where they inject toxins, suck sap, destroy grape vines, hibernate, and — having read the books on sustainability, thinking ahead and all that — reproduce parthenogenetically for up to seven generations. If the spring weather feels just right after a winter hibernation, they rise with the sap to the leaves. Or wander off to new plants. Or grow wings and fly to new plants.
Some insects, not wishing to go to the bother of actually changing form, are more imaginative in their adaptations. As a class, insects have developed multiple uses for what appear to be simple appendages. In Planet of the Bugs, Scott Richard Shaw reflects on insect legs. “Insects use their legs,” he says “for walking, running, hopping, fighting, grasping food, tasting food, grooming their body, swimming, digging, spinning silk, courtship, sound production, and even hearing.” These multiple uses of jointed limbs are but one of many characteristics that have allowed these animals to diversify, to occupy so many niches and offer so many services to natural systems, including the provision of food for humans.
As well as being small, reproducing like crazy, evolving multiple-use appendages, and undergoing complete metamorphosis, many insects pretend to be something other than what they are, excelling in the arts of camouflage and mimicry much more than Navy SEALs or Bigfoot. We all know about stick insects, but have you seen the lichen-colored katydid, the leaf-litter mantid, the walking flower mantis, or the walking leaf mantis? Even if you had seen them, you likely wouldn’t know it. They look like sticks, lichens, leaf litter, flowers, and leaves. If you are very, very patient, you may see them walk, or fly. That’s usually a giveaway, which they know deep down in their DNA, so that if you are impatient and try to make them move, they usually don’t oblige, having grown up with the story that their mother repeated until it was ingrained in their DNA. “You know your grandpa on Mom’s side? He moved. And then he was eaten.”
Finally, generating large populations is, in evolutionary terms, necessary but not sufficient. Unlike dinosaurs and trilobites, many insects survived major global catastrophes that wiped out other species (to the survivors belong the spoils). Going back a few hundred million years, into the Permian period, beetles have had the lowest family-level extinction rates of any species. This is attributed at least in part to their varied diets and the diverse ecological niches they inhabit. Insects are survivors.
For entomophagists, how these millions are organized is as important as sheer numbers. Some are more appropriate for foraging, or loose semi-management, while others lend themselves better to agriculture. Those insects that produce large numbers within closely organized societies — the so-called eusocial insects such as termites, bees, and ants — are much more difficult to farm intensively than those that have lots of young without being organized into colonies, such as crickets, silkworms, moth larvae, and flies. Bees, which are considered domesticated and are used as inputs for industrial agriculture, are
in fact not so well suited for the economic box into which they have been stuffed, and they suffer for it.
The large number and diversity of insects, and their strategies for having achieved world domination, are impressive — and pertinent to which ones we might like to eat and how we might most efficiently harvest, or grow, them. But before we dive whole-bug into the mealworm bucket and make them part of our daily diet, we may wish to further determine whether eating bugs is good for us. Would persuading more people to eat insects result in a healthier population and a more resilient biosphere?
SHE SOMETIMES GIVES ME HER PROTEIN
Insects as Nutrition
The more we go inside,
the more there is to see.
Recent popular and scientific literature repeats general claims that insects, as a source of human protein and energy, are at least as good as — and probably better than — other livestock, and in terms of their ecological and social impacts, much better. If one examines the bases of these claims, however, the evidence is more ambiguous.
In 2010, FAO published a collection of papers from a workshop that was held in Thailand in 2008, titled Forest Insects as Food: Humans Bite Back.18 The author of one of the report’s chapters repeated a claim, first published in 1960, that whole bee combs, brood (babies) and all, “come close to being the ultimate food and health supplement in terms of calories and a balance of carbohydrates, proteins, fats, minerals, vitamins.” In another chapter of the same report, an author states that dried silkworm pupae (Bombyx mori) have calcium levels equivalent to milk or peas, and might be an alternative source of calcium for people who are milk-intolerant, or in countries such as China where dairy products are not often part of the diet. The author then claims that, with about 50 percent protein and 33 percent fat, it is “commonly said that three silkworm pupae are equivalent to one hen’s egg.” These statements about the nutritional value of eating beehives and silkworm larvae may be true, but if we are going to incorporate them into a global food strategy, we might wish to have evidence that is slightly more reliable than what is “commonly said.”
Much of the enthusiasm for the nutritional value of insects has been based on anecdotes, or on single studies that have not been replicated. The scientific quest since the seventeenth century has been to attain a state of knowledge about the world in which everything we claim to know is falsifiable; that is, we should be able to design a research study that could disprove the claim. If the claim survives many efforts at disproval, we accept it, at least tentatively, as being true. The kinds of studies that are considered acceptable in the conventional scientific world must follow a set of strict protocols. Because of this, many scientists have learned to be skeptical of indigenous or anecdotal claims. For instance, until the claims of effectiveness for traditional Chinese medicine could be replicated under controlled conditions, in which results of treatment were tested against placebos or other treatments, they were often summarily dismissed as folk tales. Similarly, promoters of fermented wasp shochu (made from Asian giant hornets) in Japan tell stories of how drinking it will improve one’s skin and cure fatigue. The stories may be true — or true sometimes, and in some places — but until they are tested under controlled conditions, scientists tend to be skeptical. The effects we hear about in these stories may be “just” placebo effects — people getting better, or losing weight, or being more fit because they thought the medicine or the food was good for them, or because social circumstances quite apart from the medicine or food were what actually produced the effect. The so-called Mediterranean diet, for instance, may promote one’s health not because of some magic chemicals in the wine or olive oil, but because the social context in which many Mediterranean people eat — with friends, at a leisurely pace — may be conducive to reducing stress and promoting health.
Having said that, we may irretrievably lose a lot of important information if we simply and arrogantly dismiss any and all anecdotal claims as “unscientific.” It may not be that a specific chemical in the wine, or the insect, is of value, but we can still learn a lot by paying careful attention to information passed down through many generations of naturalists and healers. Without some replicated evidence that they are “bad” for us or for the planet, we are fools to simply dismiss traditional cures and stories.
The lack of replication is not peculiar to entomophagy; as formal reviews of the scientific literature in the twenty-first century have discovered, many scholarly studies — including many of those assessing the effectiveness of drugs we use in our medical system — have never been replicated. What this means is that the humility and uncertainty with which we approach entomophagy’s claims should be applied to all claims of cures and panaceas, including those endorsed by scientists.
One of the ways to come to grips with this is to look at a variety of sources of information, to see if they agree. This is called triangulation, and it is one of the better ways of drawing on multiple, very different, sources of information. We may not be able to conduct a randomized clinical trial on claims of sustainability and health, but we can have greater confidence if the information we are using is verified by several sources and from a number of different perspectives. In doing this, we need to pay careful attention to some details. Are the reports of nutrient content on a dry-weight basis (which makes it easier to compare across species of animals — crickets to cows, for instance) or on an as-eaten basis (which allows us to better assess how nutritious the food is on the plate)? Was the research based on using different laboratory tests and under different conditions? Does the nutritional content of insects vary from season to season and ecosystem to ecosystem? While we can draw some general, and useful, conclusions about the value of bugs as food, we should certainly back off from making grand statements of unwarranted precision (decimal points in food values always make me suspicious).
Recognizing these problems, some authors have attempted to formally bring together information on the nutritional value of insects. In the absence of specific breeding and feeding programs, we would expect this information to remain stable. Certainly if we wish to make food-guide recommendations, we must assume this level of stability. Even for animals that have been intensively manipulated, such as chickens and cows, generalizations about protein, fat, and micronutrients are more or less stable over time, although these vary by breed, diet, and cut of meat. This leads us to expect that we might see general patterns, and variations within those, among insects according to species and feed sources as well.
A 1997 review by Sandra Bukkens at the National Institute of Nutrition in Rome seems to have set the baseline and the tone for pretty much everything that followed. Bukkens concluded that, in general, as a group, insects “appear to be nutritious. They are rich in protein and fat and provide ample quantities of minerals and vitamins. The amino acid composition of the insect protein is in most of the cases better than that of grains or legumes and in several cases the food insects may be of importance in complementing the protein of commonly consumed grain staples among indigenous populations.”19 In the two decades between 1997 and 2017, the number of reports, claims, and original research studies has multiplied faster than a room full of bugs. Most would concur with Bukkens.
Julieta Ramos-Elorduy, a long-time researcher into, and advocate for, edible insects in Mexico, has published some of the more carefully designed studies. She and two other researchers reported in a 2012 paper that the edible Orthoptera (chapulines) of Mexico that they sampled had protein levels ranging from about 44 to 77 percent (note the big range). These protein levels were similar to soybeans (about 40 percent), eggs (about 46 percent), beef (about 54 percent), and chicken (about 43 percent), but lower than fish (about 81 percent). The chapulines contained more energy on a per weight basis than vegetables, cereals, and meats, with the exception of soybeans and pork. “The quantity and quality of the nutrients [of] these edible orthopterans,” the authors asserted, “provides a significant cont
ribution to the nutrition of the peasants who eat them.”20
Much of this material sounds promising, although the claim that eating insects was good for “the peasants” makes me uncomfortable. Just the peasants? Prospective entomophagists, walking into the data on the nutritional value of eating insects, can feel as if they have stumbled into the Fire Swamp in The Princess Bride. How should they interpret all these numbers?
Fortunately, I had not quite sunk irretrievably into the Fire Swamp’s lightning sand when, at the end of 2015 and the beginning of 2016, I was rescued by two rigorous scholarly reviews that brought together and evaluated all the information available (at least in English) on the nutrient composition of edible insects.
In a 2015 paper, Charlotte Payne and her colleagues from the UK and Japan asked the question, “Are Edible Insects More or Less ‘Healthy’ than Commonly Consumed Meats?”21 To answer this, they conducted a systematic review of the scholarly literature and focused on six categories of edible insects:
Species gathered from the wild and sold commercially as human food: Vespula spp (wasps) in Southeast Asia; Macrotermes spp (termites) in sub-Saharan Africa.
Agricultural pests harvested for human consumption: Encosternum spp (stink bugs) in Southeast Asia and sub-Saharan Africa; Oxya spp (rice grasshoppers) in Southeast Asia.
Traditionally wild-gathered species, sold commercially as food, for which farming methods are being developed: Rhynchophorus phoenicius (palm weevils) in Asia, Africa, and Latin America; Oecyphylla smaragdina (weaver ants) in Southeast Asia.
Eat the Beetles!: An Exploration into Our Conflicted Relationship with Insects Page 4
