Minilivestock: an ecologically sound food source

Are humans herbivores? Heck no, is the short answer. Even most herbivores aren’t exclusively herbivores. For example, deer are known to eat the nestlings of ground-nesting birds, if they are deficient in certain minerals that they need to grow antlers. Most primates eat insects as a supplement to plants, along with occasional meat. Human digestive systems and teeth are obviously designed for an omnivorous diet.

What started this line of thinking is that I just spent a little too much time responding to some ill-considered comments on a vegetarian message board. I was surfing for good recipes to feed my cheese-itarian fiancé. When I ran into ridiculous assertions that humans can’t digest meat and have herbivore teeth, I felt compelled to respond.

There are excellent arguments for a vegetarian lifestyle, but “humans are biologically herbivores” is simply not one of them. Basic palentology shows that we have what are called “bunodont teeth,” a type of tooth found in omnivorous animals. Herbivore mammals have much taller “hyposdont” teeth that can last longer when worn down by a gritty, plant-dominant diet. Primitive stone tools tell us that 2.5 million years ago early hominids were using stone implements to cut the flesh off the bones of large animals that they had either hunted or whose carcasses they had scavenged. Our digestive systems are clearly designed to digest animal proteins, beginning with pepsin in the stomach. The bottom line is that, historically and biologically speaking, we are omnivores.

What many of us in developed countries have “forgotten” is that an omnivorous diet can include insects. And it just might be a good idea for the environment.

Entomo-what?

Honeypot ant

Entomophagy–eating insects, arachnids, and myriapods–has been a successful dietary strategy for humans for tens of thousands of years (at least). Insect foods remain a popular in Central and South America, Africa, and Asia. There are an estimated 1,462 species of edible arthropods including crickets, cicadas, grasshoppers, ants, beetle grubs, caterpillars, scorpions, and tarantulas. Depending on the culture and customs, insects may be skewered, fried, smoked, baked, or eaten raw. In Australia, aboriginal peoples consider honeypot ants, whose grape-sized abdomens are filled with with sweet liquid, a delicacy.

OK, now you’ve really grossed me out!

Why bring up this topic that is likely to turn your stomach? If you’ll permit me a moment on my soapbox, I think a thoughtful semi-vegetarian and low-dairy diet is a moral imperative for everyone on the planet. We need to reverse the trend of large, specialized farms for meat or dairy, because they have a significant environmental impact. A  study on the environmental impacts of dairy in the UK found that intensive dairy farms overwhelm the local ecosystems to damage habitat, reduce biodiversity, damage soil, increase use of fertilizers, medications and hormones, and pollute groundwater (skip to page 151 to read the conclusions for yourself). So ovo-lacto vegetarians are not off the hook. They are contributing to the problem.

But you just said we were omnivores. Don’t we all need protein?

Grasshoppers on a skewer

Of course we all need protein (more specifically their building blocks, amino acids). Plant sources are unlikely to provide enough. Unless we can each return to keeping chickens and a cow on family farms, where we would live with the immediate environmental impacts of our dietary choices, we need to develop a cultural solution. One promising solution–if we can just get over the ick-factor–is minilivestock, or the cultivation of insects for food.

Some of the benefits:

  • Insects generally contain more protein and less fat than traditional meats, according to the Entomological Society of America.
  • They also have about 20 times higher food conversion efficiency than traditional meats, meaning they have a higher meat-to-feed ratio than beef, pork, lamb or chicken.
  • Insects can be a good source of not only protein, but also vitamins, minerals, and fats. For example, crickets are high in calcium, and termites are rich in iron. Giant silkworm moth larvae provide copper, zinc, iron, thiamin, and riboflavin.
  • One study noted that food collection of a crop pest grasshopper, Sphenarium purpurascens, may be a viable alternative to pesticide use in Mexico’s Puebla–Tlaxcala Valley. Collection of pest insects for food has a long history.
  • We eat them anyway. Some estimates suggest that we eat from one to two pounds of insects each year, and without knowing it. We might as well make it a conscious part of caring for the environment.

Some interesting reads:

For Most People, Eating Bugs Is Only Natural

Edible Insects

Entomophagy and space agriculture

Buggy recipes

Feeling brave? You can buy insect foods online.

Media Worth Watching: Insect News Network

Insects can use more friends on the Web. Emmet Brady is one such guy. A little bit hipster, a lot bug geek, Emmet is a dedicated promoter of cultural entomology. Cultural entomology studies the intersections between humans and insects, many of which are likely to have important implications as the climate changes, food production is threatened by the loss of pollinators, and more people on the planet require more protein. So, kudos to you, Emmet. We’ll have our eyes on your work!

http://www.insectnewsnetwork.com/

Beautiful Bug Art

Looking at insects through a dissecting scope is one of my favorite activities. I love seeing the gorgeous textures and colors up close–it’s like entering a secret sci-fi wonderland, where you can get intimate with the alien without it eating your head. I especially like this “fantasy” world because it’s real–and because human lives are entwined with these marvelous tiny beings, even if we aren’t generally aware of it.

Not everyone has the equipment or inclination to gaze at insects through a scope, however. For them, artists can provide an accessible aesthetic for enjoying insect beauty. Mielle Harvey is my latest find. (Actually, she found me on this blog–thanks Mielle!) Her HEXAPODA collection is both artistically sophisticated and scientifically accurate enough to suit both art aficionados and entomology buffs. Check it out!

http://www.mielleharvey.com/the-hexapoda-collection

CicadaeGoldenEgg400 Cicadae and Golden Egg

Cicadae and Golden Egg, by Mielle Harvey

Starvation-sleep link?

Recent research suggests that sleep may not be an absolute necessity–if starvation looms. An August 31 study published online in PLoS Biology shows that fruit flies remain active and alert when in a foodless environment. The research team speculates that the lack of consequences from sleep deprivation may be tied to lipid metabolism.

But don’t stop eating to burn the midnight oil–another recent study links late nights to Alzheimer’s.

Read more here: Hungry flies ok with less sleep.

Aphids hate goat breath

The aphids don’t want to be lunch–so how do they avoid becoming a mouthful when an herbivorous animal tries to eat the plant they live on? A new study published in Current Biology finds a simple solution–the heat and the humidity of the goat’s breath triggers the insects to drop off the plant.

via ScienceShot: Humid Breath Fells Insects – ScienceNOW.

Big girls + little boys = gravity defying spider action

Spanish researchers have found evidence that the combination of behavior and gravity may determine the itty-bitty body size of some orb weaver males. The males use “bridging”, or crawling along a single strand of silk to another location, to get around, a behavior that appears to favor smaller size. Females, however, are larger because this gives them a reproductive advantage: producing more eggs. This has led to what is called extreme sexual dimorphism, or large differences in size between males and females.

Source: BBC News – Spider size is a question of gravity.

WebMD helps you identify bugs and their bites

Adult flea

Are you ready for a summer of no-see-ums and bloodsuckers? If you feel a little unprepared, here’s something to inspire you, courtesy of WebMd.com: health education, dermatology, and nice macro photography, all rolled into an informative slideshow.

Bad Bugs Slideshow: Identifying Bugs and Their Bites

After you’re through, you may want to read this:

6 Insect Repellents Get High Marks

For you lovers of natural products, one repellent uses lemon eucalyptus oil. For the rest of you, remember: never use a repellent with more than 30% DEET.

Here’s to a happy and healthy summer!

Arts: Swiss Artist Catalogs Mutant Insects Around Nuke Plants

Illustrations by Cornelia Hesse-Honegger

Arts: Swiss Artist Catalogs Mutant Insects Around Nuke Plants

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First pigment-making animal is an aphid!

How cool is this? A species of pea aphid appears to have picked up the genes for making carotenoids from fungi–making it the first known animal to manufacture their own. This adds to the evidence that DNA can transfer laterally from bacteria, yeast, or fungi to animals. The evolutionary story is just getting more and more interesting!

N.A. Moran and T. Jarvik, “Lateral transfer of genes from fungi underlies carotenoid production in aphids,” Science:328:624-7, 2010.

More on lacewing eggs and mystical flowers

A friend of mine commented on my previous post regarding the lacewing eggs mistaken for a “rare Buddhist flower” by referring me to this article on EnvironmentalGraffiti.com, which unfortunately demonstrates some bad journalism. The article purports to “dig deeper” into the issue, but it merely muddles it with some incorrect assertions. My take on it: they want to keep all their readers happy, including those who believe in miracles–an unfortunate trait for an environmental publication.

Ficus racemosa, one of the plants traditionally considered an udumbara flower.

First, the article does little to debunk the idea that tiny flowers can grow on nun’s washing machines. It proposes several types of real flowers that are traditionally called udumbara, all of which are trees or lotuses (see above photo). Somehow, however, the author misses that that small “flowers” growing off of metal surfaces or Buddha statues could not be any of these udumbara. The bottom line: plants need accessible nutrients to grow. Washing machines are not generally a good place to grow roots and absorb nitrogen. To believe otherwise demonstrates, in my mind, a lack of any sort of desire to use rational thought. The Hindu concept of Maya applies here–humans’ fundamental illusion is that we are somehow separate from the universe (and nature). This separation, reinforced by a lack of education, is what makes us believe in the necessity of miracles. The irony is the world is plenty fabulous without magical thinking.

Second, the author’s assertion that lacewings are not common in China is simply not true. There are at least two lineages, each with multiple species, that occur in China. For instance, the Chinese green lacewing (Chrysopa sinica) is an important predator for aphids affecting the Chinese cotton crop.

OK, enough of my rant. For your reading pleasure, here’s a link to some interesting lacewing information, including more about the properties of the egg stalks and research about whether they could be used to produce silk: http://biocontrolbeat.wordpress.com/2009/09/28/lacewing-silk/ . Cool, huh?