The Energy Chain
Ever wondered why we don’t go around hunting mountain lions for dinner? Obviously, there might not be many lurking around your part of the world, but this applies to practically all carnivores. Bears, big cats, small cats, we haven’t made a habit of eating animals on the upper echelons of the food chain. Even when winding the clock back to a time when they roamed the land in significant numbers, before we competed them off the map.
The answer for the lack of lion on the menu, lies in the bioenergetics of the animal food chain. Also known as trophic level. Energy has to start somewhere, and it all originates from solar energy beating down on mother earth. Animals are closed off at this stage, but plants can take in and convert that energy through photosynthesis. Then animals that have the ability to digest plants, eat the greens and enter the energy chain.
At this point, carnivorous animals can join in by eating the animals that can absorb plants. And there you’ve reached the top of the food chain with three steps. There can be more levels to this, like an eagle catching a snake that’s recently gorged on a baby rabbit that likes munching on grass. The trophic level, which determines the steps an animal has to take to receive energy, caps out at 5.
In case you’re wondering, modern estimates of our place in the energy chain puts us at a trophic level of 2.21. Right around the diet of pigs and anchovies. It’s more of a reflection of the current diet than an actual species-appropriate one. All the signs point to a higher trophic level during the Pleistocene, the period that spanned the vast bulk of humanity’s existence.
So Why Eat Ruminants?
Looking at the energy chain in its basic form, two thoughts might pop into your head.
- Why don’t we just skip the middle-men and eat plants?
- If we are meant to be apex predators, why don’t we make a regular habit of eating other carnivores?
The Second Trophic Level
Here’s the thing, we gave up the right, or I should say ability, to eat plants a long time ago. Several million years back in the distant past. We traded gut space for brain size, and with that our cognitive capabilities took a drastic turn for the better. But with the cutbacks along the digestive tract, with the colon taking a big hit, we lost out on plant power. Cellulose, an insoluble fiber, is the most abundant organic compound across the planet. Gorillas get to use cellulose, but humans cannot. In fact, fiber can only support up to 4% of our energy needs.
If you go back far enough, you would find a time where we’d be happily munching on leaves and twigs. But at that point, our ancestors hadn’t stepped into the human line, they still functioned and ate like standard tree-hopping primates.
As it is, our digestive system just doesn’t have the capabilities to enter in at the second trophic level. That’s exhibited by terrible absorption rates of plant nutrients. There’s little to no chance you’re getting enough Omega 3 by drowning in flaxseed oil. That alpha-linoleic acid still has to convert over to usable EHA and DHA, which doesn’t go very well. Its effect on brain-boosting DHA is minimal at best.
The Fifth Trophic Level
There’s strong evidence pointing to the status of early humans as master hunters. We came in as omnivores, found a taste for meat in leftover carcasses, then developed the tools to do the job ourselves. Business continued to pick up, we couldn’t help ourselves, and we wiped out a huge chunk of the world’s megafauna. Carnivores like cave bears and cave lions were among the casualties of the Quaternary Extinction Event. But while there is some evidence of humans hunting carnivorous animals, they are rare finds compared to the herbivore contingent. More than likely, early humans only hunted carnivores during times of scarcity, and as part of rituals. Competition for resources did the rest, and it’s worth remembering that we did a great job exterminating their prey.
Beyond that, carnivorous animals aren’t exactly prime Sunday roast material. The meat is tougher, leaner, often toxic, and isn’t the easiest to get hold of. Whereas the herbivore meat packs on the fat, rarely have toxins, and is far more abundant. Protein is great for building critical structures in the body, not so great when leaned on as a fuel source. We weren’t so much meat hunters, as we were fat hunters. So while our stone-age ancestors were apex predators in the sense that they dominated the competition, they wouldn’t have been anywhere near level 5.
The issue here, is that with each hoop that solar energy has to go through, huge chunks get lost. Some get used for sustaining life, some get flat-out wasted. The net effect is that up to 90% of the inbound energy doesn’t make it up to the next trophic level. Animals on the higher echelons of the food chain are left with scraps, and that in turn keeps their numbers in check. There simply isn’t enough energy to go round when you’re operating as an apex predator.
For 7 odd billion humans, the lower down the trophic ladder we go, the more sustainable our population becomes. For the record, we’re already running on red when it comes to feeding the people, but let’s say we make the best of a bad situation.
The Masters Of Fiber
Since we don’t have the digestive tract to come in at level 2 and nibble on grass stalks all day, we need an animal that can slot in and perform that role for us. Monogastric animals like pigs can certainly eat grass, but there’s a cap on their ability to use fiber. Kunekune pigs being a notable exception.
Ruminants on the other hand, are more than capable of taking on fiber. In fact, it’s their specialty. This group includes cows, sheep, goats, and deer. They all share in the uniqueness of having four stomachs. The foremost chamber in the stomach, the rumen, contains bacteria that feed on fibrous food. As a result, the hosting ruminants can easily breakdown and convert plants that are otherwise inedible for humans.
This rumen isn’t restricted to turning fiber into digestible glucose. It also is perfectly adept at turning glucose into saturated fats, and unsaturated fats into saturated fats. The implication here is huge. Throw whatever you want at the cow, and it’s going to turn it into money. Saturated fat is resistant to oxidation and extremely stable. It provides us with clean bioavailable fuel, that can also go towards the cement that makes up your cell structure. Then there’s the whole appetite-suppressing mechanism that prevents overeating. To sum that all up, saturated fat is a highly efficient source of energy, and ruminants specialise in its production.
This is shown by the following facts.
1. Pigs and chickens, as monogastric animals, have high amounts of polyunsaturated fats in their meat, especially when fed a high PUFA diet (polyunsaturated fatty acids). Grain feed, despite being seen as a carb source, contains plenty of PUFA. Neither animal is able to convert PUFA into saturated fat, and therefore stores it in its original form.
Which is highly inflammatory, prone to oxidation, and nutritionally bereft. Along with the complete lack of appetite suppression, and a potential source for pathological insulin resistance. The bad kind.
2. Cows fed grain, and therefore a high PUFA diet, still show up with negligible differences to their compatriots reared on grass. A little less Omega 3, a touch more fat, and that’s it. The meat is still packed with saturated fat, showcasing a rumen that’s done an incredible job of converting toxic waste into prime nutrition.
It’s Not Just A Matter Of Nutrition
By focusing on ruminant meat, we’re slotting in nicely at a highly efficient level 3. Ruminants are capable of digesting many different plant compounds, and humans are equally capable of breaking down meat. Hence the penchant for fire, highly acidic stomachs, and enlarged small intestines for absorbing fats and proteins. We’re making the absolute most of the energy chain, with minimal casualties.
Beef, as long as you’re bringing organs into mix, contains the full spectrum of nutrients needed to sustain optimal health. All this is the result of a system that specialises in converting plant nutrition into animal-friendly compounds.
In this partnership, we get more than nutrition. It sketches out a model for sustainable agriculture, that could be our best shot at keeping food production from buckling under the needs of runaway population growth. Plant resources get used to their maximum potential, the organisms that inhabit the soil are fed by energy returned by the ruminants. Those little creatures in turn are able to power the plants. It’s a loop where energy is used to its full potential.
It’s worth adding an asterisk to this model. The meat industry doesn’t widely practice this method of regenerative agriculture, as factory farming provides better profits. But even in the case of factory farming, grain-feed only makes up a fraction, and grass still takes up the bulk of their diet. United Nations FAO research has shown that only 13% of global animal feed was made up of grain. When looking at cattle, that number came down to 10%. Leaving 90% of cattle feed to be made of matter inedible for humans. And yet vegans will continue to claim that livestock are stealing their dinner.
Monocropping, on the other hand, is rapidly depleted the world’s topsoil, and in the US it’s receding 10 times faster than it can be replenished. The global topsoil, according to the FAO, will run out within 60 years. At which point, we’re deeply screwed. No topsoil, no plants, no food.
The same UN study on animal feed also concluded that 80% of the global agricultural land allocated to feed production consists of grassland and that over half of the grassland cannot be converted to cropland. So would those areas be best served for inefficient grain production that’s hurtling towards ecological disaster, or for rearing cattle that can actually improve the topsoil?
Naturally, and this continues to be a hot-button topic, the problem of cow farts gets brought up. This is because livestock accounts for up to 14% of all human greenhouse emissions. Cows get the brunt of the stick for their methane burps. It’s an imposing statistic, as long as you’re willing to ignore the fact that these carbon emissions are part of a biological cycle. Grass has the carbon, cow eats the carbon, out goes the methane into the atmosphere. Then 10 years later, the methane gets broken down into carbon dioxide and water, and is eaten up by the plants again.
If this chain is happening without nature-breaking human intervention, it’s reasonably safe to assume that the planet can handle it.
But what if we extracted ancient carbons from deep underground, releasing them into the atmosphere, where they remain for thousands of years? That’s what we’re doing with fossil fuels.
Ruminants aren’t just the ideal form of nutrition, they are a critical part of the ecological chain that we literally can’t afford to pass up.
The Ruminant Package
- Limits wasted energy
- Converts inedible matter into prime nutrition
- High saturated fat content
- Lowered Omega 6 content
- Contain the full spectrum of nutrients needed to live an optimal lifestyle
- Environmentally sustainable
- Crucial for retaining the topsoil
- Necessary to feed the global population
This isn’t a discussion of the ethics of eating meat, that deserves its own topic. Instead, this article is a simple look into the bioenergetics of the food chain, and just where humans might slot into it.
There’s a very good case to be made that humans evolved to be meat-eaters, and fat was clearly a prized part of the menu. While the megafauna of old are long extinct, ruminants linger on as the next best option. Ecologically appropriates, evolutionarily compatible. It all appears to sync up rather nicely.