Many years ago, I interviewed a nutrition scientist who gave me the most cogent explanation I ever heard – before or since – for our obesity epidemic.
He’d done some work at a zoo, and he had a problem with overweight orangutans. They’d gotten used to eating foods other than the fruits and greens that are their native diet, in part because well-meaning people wanted to donate food to the zoo rather than let it go to waste. Give orangutans papayas and tree bark, and they regulate their own diet. Give them donuts, and they get fat.
Like us, the apes recognize that donuts taste better than what the rainforest has on offer, and the genes that evolved to give them a preference for fruit go into overdrive when presented with a chocolate cruller. Not only that, when you try and get them to go back to tree bark, they throw tantrums and start winging poop around.
Humans evolved to eat a diet not dissimilar from that of our closest cousins, and Krispy Kreme has been our undoing just as surely as it ruined the girlish figures of apes in captivity.
We’re orangutans with donuts, and the ready availability of high-fat, high-salt, high-sugar (read: delicious) food seems to throw all our self-regulatory mechanisms out of whack.
Small children have been shown to regulate their own intake, and can effectively keep their energy intake and output in balance. Once they hit the ripe old age of three, though, all bets are off. From toddlerhood on, food palatability (and its partner in crime, portion size) strongly influences how much we eat.
Animals, by contrast, are pretty good at self-regulation. Fat chickens are a product of science, not gluttony. The birds had to be genetically manipulated to eat a lot and grow quickly. Even so, the only way to grow meat birds economically is to keep them confined and feed them high-protein, high-calorie food. If you let them out, they’ll revert to their calorie-burning, grass-eating selves and self-regulate you right out of economic feasibility.
I’m worried about precisely the reverse. Our chickens free-ranged all summer and fall and, although they always had pellets, I trusted their chicken instincts to eat what they needed. I didn’t have to pay attention to their diet because they did.
Because it’s winter now, we keep our chickens locked in their run almost all the time. The smorgasbord that is our property is barren – no bugs, no greens – so there’s no point in exposing them to do the danger of predators. That means it’s up to us to make sure they have everything they need.
In theory, the layer pellets we feed them provide the full nutritional complement. In practice, I worry. I’m sure they’re getting plenty of protein and calories, but I’m concerned about calcium.
Humans need calcium for (among other things) strong bones. While chickens also need strong bones, they also need strong eggshells. Kevin thought that our chickens’ shells seemed to be getting a little fragile, so we decided to give them a calcium supplement.
The calcium supplement of choice is crushed oyster shells, and it runs about $8. for a small bag at our local feed store. Uncrushed oyster shells, by contrast, are free for the taking in the giant shell pile that we’re amassing behind the compost.
Kevin dug through the pile to pick some oyster shells out from among the clam shells. Although I don’t know why people don’t use clam shells for calcium supplementation (Lower calcium content? Difficulty in processing?) we went for oyster shells because that’s what everyone uses. There must be a reason.
Kevin, having long anticipated the day we’d want to crush oyster shells for our chickens, had been keeping his eye out for items that would function as a giant mortar and pestle. When the window-treatment store downstairs in his office building closed, he appropriated a steep-sided concrete planter that was left behind.
Here’s where it gets embarrassing. All my life, I’ve been under the impression that the bowl was the pestle and the stick was the mortar. I even told Kevin, and he came up with an easy way to remember it: “The pestle is the vessel.” Turns out, though, that the pestle isn’t the vessel. The mortar is the vessel. The pestle is the stick. Sigh.
Anyway, we had a mortar, but we needed a pestle. Ideally, it would be a foot-long stick with a hard, rounded, heavy end. Kevin couldn’t find one of those, though, so he went the Paleolithic route and used a rock.
We put a handful of shells in the mortar and took turns pounding them with the pestle. Before long, they were a mix of crumbs, pebbles, and shards. Some of the particles were very small. Others were still quite large.
I was in favor of more pounding. “Some of those pieces look too big for them,” I said.
“They can swallow pretty big stuff,” Kevin answered.
I was still concerned. “I don’t know,” I ventured, “I think some of them could be a choking hazard.”
“A choking hazard?” My husband looked at me incredulously.
“Like with babies,” I said.
“You realize that they free-range all summer,” he said, clearly referring not to babies but to chickens. “And they encounter particles of all sizes, yet manage not to peck at things that will choke them.”
Oh yeah. I’d forgotten about that.
We mixed the shell with corn and some cooking oil we’d used to fry shrimp fritters, and brought it up to the coop. The chickens wolfed it down, big pieces and small. I subsequently learned that larger shell particles are better for eggshells, apparently because they spend more time in the chickens’ digestive tract, giving the birds more opportunity for calcium absorption.
All in all, I’ve been struck by the chickens’ ability to figure things out for themselves. They know what to eat, and eat the right amount. Once we configured the nestboxes correctly (our bad), our flock laid almost all their eggs in them. They know enough to come into their coop at night and roost up high, where they’d be safe from predation. As long as they’ve got an appropriate habitat – lots of space, the right kind of food, plenty of water – they know what to do.
I, by contrast, am an orangutan with donuts. I’m still trying to ditch the ten extra pounds I’ve acquired over the last year or so, but it’s very hard to do in a world full of things like the chicken liver mousse Kevin made for the Super Bowl party we went to. Any day now, I’ll hit the poop-winging stage.