Dear Science

Can You Make a Venus Flytrap Go Vegan?

Tom Dougherty

Dear Science,

I recently became a vegetarian. While I was at Whole Foods buying my protein powder, I found the perfect apartment companion: a Venus flytrap. My question is, assuming I do not have enough bugs in my apartment to feed this carnivorous plant, can I keep my new-found pet alive on a vegetarian diet? Can I feed it tofu and rice? Thank you for your help,

Vegetarian Venus Lover

Dear VVL,

Science has been vegetarian, well mostly vegetarian, since age 2. So, congratulations for the switch; the environment thanks you for your much lower carbon impact. As omnivores, we can get away with a vegan diet so long as we include enough balanced protein sources—like the combination of tofu and rice—to keep our eyes bright, our coats shiny, and our tails bushy.

Your carnivorous plant isn't so lucky. Here's why: Most plants need nitrogen and mineral-packed soil to grow, goodies that generally come from decaying plants and animals. The problem is, in places with an abundance of everything plants need—air, sun, water, nitrogen, and minerals—vicious competition ensues. Carnivorous plants get away from the crowd by growing in soil too crappy for other plants and instead grab the iron, calcium, phosphates, and nitrogen they need from living insects. In places where water and sun are abundant, but the soil nitrogen and nutrient poor—like the Carolina coast—carnivorous plants have a huge advantage. Yet another reason to avoid South Carolina.

The specialized skill of capturing insects makes most carnivorous plants fussy, so keeping a Venus flytrap alive is a tricky business. You'll need copious amounts of acidified water, a terrarium to keep things humid, plenty of sunlight, and some nutrient-poor soil. Dump in a bunch of fertilizer and the plant will promptly die; in the acidic water, the fixed nitrogen in the fertilizer becomes toxic ammonium. That'll kill your plant. Your flytrap wants what it evolved to consume: insects. Your new studio must have some pests you don't like. Cockroaches? Check under the fridge. If not, buy some crickets or mealworms from the pet store. Just think of it this way: You're outsourcing the meat eating in your apartment.

As for tofu—well, tofu is not made from insect viscera, despite appearances. So, no tofu and rice. Put the wrong foods in the flytrap and they'll rot, and your poor plant will kick it. It would be like feeding spinach to a cat; no good can come of it. Even bits of hamburger aren't right. If feeding prey to your carnivorous plant is too abhorrent for you, don't feed it anything. It has a better chance of living with just sunlight and water.

Even for an omnivore, becoming vegetarian is tricky. Your carnivorous flytrap is even fussier than you are. Good luck with your Venus flytrap, and with your vegetarianism. Do you know about the Society for DNA Free Food?recommended

Karmically Yours,


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Comments (4) RSS

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Venus flytraps are retarded.
Posted by Mr. Poe on October 27, 2008 at 1:23 PM · Report this
Venus flytraps are cool.
Posted by VDD on November 11, 2008 at 8:29 AM · Report this
we're not omnivores. we can't eat raw food because we're not meant to be predators. true predators have the enzymes necessary to kill the bacteria colonizing raw meat. we get sick. additionally, we're not fast enough to hunt without artificial tools and our teeth match herbivores more closely.

finally, protein is the least of a vegan's worry. protein is very easy to come by. this myth that it is difficult to get protein comes from the popularization of vegetarianism in the 1800s when people were getting sick and everyone assumed it was a lack of protein when it was most likely a lack of b12. b12 and omega 3 fatty acids are nutrients that need to be watched, but these are pretty easy to come by as well.
Posted by oh hai on March 30, 2009 at 4:29 PM · Report this
Oh hai, some notes on what we're "meant" to be:

Both of the species we are most closely related to, chimpanzees and bonobos, regularly consume raw meat. We come from omnivores, and likely evolved as omnivores in the 6 million years since we split from these lineages. Much of what prevents illness from consuming raw meat is immune response from previous exposure to such things and the community of microbes that symbiotically chill out in our guts, eating stuff so we don't have to. By cooking our food we reduce our immune exposure and don't foster happy homes for all the same microbes. But, lucky for us, our morphological adaptations correlate well with behavioral adaptations! Just because we need tools to do something, or need to cook something doesn't mean we're not adapted to eat it; we just might be adapted to both process it both outside and inside our bodies! We've been cooking meat for millennia, if not longer, and the morphological consequences (small mouths and guts from reduced internal processing needs) are pretty obvious.

Also, there are many different types of meat-eating. Humans are certainly fast enough to scavenge food others kill. What's more, a prominent argument by human evolutionary biologists is that humans actually evolved to run over long distances, possibly to run prey to exhaustion. See this paper from the journal Nature:…

This is not to say that vegetarianism isn't a great social and moral philosophy, but lets not act as though you're somehow returning to nature. What we do adaptively is not necessarily what ought to do morally. Hell, I might be "meant" in an evolutionary sense to try and sneak copulations behind my spouse's back and kill off my enemies, but that doesn't make it moral.
Posted by beak3chimps on April 29, 2009 at 1:54 PM · Report this

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