06 April 2010

Carnivorous Plant May be Vegetarian (but not vegan). Eating them, not so much.

A cultivated Nepenthes rajah
Note:  You also may be interested in another post:  A Partial List of Edible Carnivorous Plants and Fungi.

I read recently about a new study: Trap geometry in three giant montane pitcher plant species from Borneo is a function of tree shrew body size. The study describes how one of the largest carnivorous plants in the world, Nepenthes rajah, may have evolved not to eat animals, but to eat poo. And you thought that it was just a coincidence that it looks like a toilet. Though I guess in Borneo they use squat toilets, but whatever. The study shows that the distance between the 'seat' and a gland that extrudes a nectar-like substance on the 'lid' is the exact height of a local tree shrew, Tupaia montana. Now before you think they just were measuring animals at random, these critters poop where they eat (despite any advice to the contrary), to mark their territory and keep away any competitors. However, when feeding from this pitcher plant, the feces fall in the 'bowl' of the plant, and the plant becomes a coprophage.  And if anything needs a picture it's a tree shrew pooping in a toilet plant, so if anyone has one, please send it my way.

I'm sure that N. rajah is not picky about what ends up in it's bowl for it to 'eat,' so it's not really 100% vegetarian (some treeshrews and mice do fall in and die).  It does make the whole diet nomenclature seem kind of silly.  'Vegetarian plant' sounds weird to me (though admittedly 'vegetarian' is not a very specific term to say the least).  Especially for eating feces.  And especially since I put manure on my vegetables in my garden, and they 'eat' that.  Sure a special organ made to trap animals and/or animal byproducts is a little more advanced than just sucking up whatever from the roots, but many plants excrete enzymes from their roots to digest organic material before it is absorbed by the roots.  But again, that is even less specificity than just having a bowl for stuff to fall in, and definitely less than having one set up to be a treeshrew rest stop. 

Capsella bursa-pastoris
Would you eat a carnivorous plant?  How about a vegetarian plant?  Or a hypothetical vegan plant?  The only example of the former that I've seen for sale as food is the possibly protocarnivorous plant Capsella bursa-pastoris, commonly known as shepherd's purse.  I have eaten this before I knew what it was, in frozen steam buns I got at an East Asian grocery store.  I now avoid it, because it's just as easy to do so, and then my conscience is clear.

Another edible protocarnivorous plant is Proboscidea spp., or devil's claw.  Here is a blurb on it from Southwestern Endangered Aridlands Resource Clearing House:

Proboscidea parviflora seed pods
Cultivated by many Southwest tribes, the seed is rich in oil and protein.[...] Dried seeds can be peeled and eaten[...]. The young fruits, when still tender, can be cooked as an okra-like vegetable.
Drosera rotundifolia
Proboscidea are also used to make baskets, which you may or may not consider vegan.  I read some chatter that that Sarracenia purpurea (purple pitcher plant) and Drosera rotundifolia (common sundew) are used in traditional medicines, and the latter possibly in some modern ones.  Would it be ethical/vegan to use these medicines?

I'm not sure if N. rajah is edible, or even if anyone has tried eating it, though I can't see how the treeshrews are being particularly exploited.  Undoubtedly if the toilet plants were commercially cultivated I can imagine some horrible fate for the treeshrews akin to foie gras ducks.

So as always, let me know what you think.  Where do you draw the line?


04 February 2010

The 'Natural' Human Diet

Creation Museum - Kentucky
Oftentimes, I have an idea for a post and I procrastinate. Then something else comes to my attention that dovetails with the original idea.

Such is the case now when I watched the Daily Colbert tonight, where the guest was John Durant. He spoke about his new "caveman" diet/way-of-life that he thinks is our one true diet. We should be eating more meat, and no bread. People in paleolithic societies live to ripe old ages as long as they don't die in early childhood. All our diseases are due to our eating "modern" (read: 'processed') foods. And other such nuggets of folk wisdom.

Now you may think that the whole fAtkins diet rebranding gets my knickers in a twist because it's contrary to the vegan thing you heard I like. But that's only a small reason, if any. Mainly it's this whole nostalgia for the past that never was. The cartoon version of primitive humans taking a bite out of a mammoth simply isn't true. I think Wikipedia has a good summary. The concept is just a continuation of the whole natural-is-automatically-good-for-you mantra that just bugs the heck out of me (arsenic, uranium, strychnine, poliovirus, all natural! they must be good for you!)

Durant's main point seems to be that we should eat the diet we have evolved to eat. He just thinks that in the 10,000 years since the dawn of agriculture humans have not evolved.

This brings me to the original item I was going to post, that shows that we have evolved since then. It points to an event that changed our bodies more than agriculture has, that being that Promethean moment we started cooking. Primatologist Richard Wrangham has many interesting points in the podcast, and I plan on digging in to his book (pun intended) for more.

The point that stuck out for me, especially as someone who has done more polyacrylamide gel electrophoresis (PAGE) than is probably good for them. As anyone who has poured their own gels, or had to dispose of used gels knows (or perhaps, only those of the above who read the MSDS), the acrylamide monomer of the gel is described as a potent neurotoxin (atleast when tested on cats).

Yet our friend C3H5NO is found in starchy cooked foods that most of us eat every day. Those very same unnatural breads and pastas and baked potatoes that raw-foodists and paleo-dieters flee from. How can this be? Richard Wrangham and others (including your humble narrator) think this is one of many evolutionary adaptations that modern H. sapiens has gained since cooking and processing food.

And I find it especially funny (if morbidly) that much of the negative health indications derive from animal tests, as in the aforementioned one with the poor kitties. If we tested chocolate on dogs, we'd never be able to eat that either (and that's a processed food too). But if we tested all-natural raw strychnine in guinea pigs we'd be in for a shock when that product hit the shelves.

Im not saying we should all load up on deep-fried vegan twinkies, I just think we should eat healthy, and not eat something because it's natural. And of course, eat without killing animals. But you knew that.

24 January 2010

If we Find out What we Eat, Do we Find out What we are?

A few new techniques have popped up that are illuminating the food web a little more clearly.

The first caught my ear through the Science Friday weekly video. Two NYC high schoolers, Brenda Tan and Matt Cost, took samples of a number of food items (as well as some amusing non-food specimens) sequenced thw COI gene in the mitochondrial DNA, and checked the 'barcodes.' This method is fairly robust, because using mitochondria you can type from hair and other non-cellular samples, and "even sequences as short as 20 nucleotides could be used to match to just one of the tens of thousands of species in the database."

The project is billed as this general interest science piece, but it has implications for the target demographic of this blog in a few ways, mainly relating to proper labeling. In this project and in a previous project done by the same mentor, many mislabeled products. A few were engangered species, including Sebastes fasciatus, or the Acadian redfish. Though the main trend was to 'downpour' and sell cheaper, more common species in place of rarer and more expensive ones. Even so there is an impact on the environment. Depending on who is doing the mislabeling, as it could be the original fisherman or harvester, this would be skewing much of the data being collected on sustainable wild harvesting of many foods. As this technology becomes more readily available it will be easier to have more accurate and less obfuscated information at the disposal of conversation groups and so forth.

Another point of interest I saw in this project was that this approach can easily be used by vegans in more focused truth-in-labeling tests, similar to those mentioned previously here. And in fact, would be cheaper and more accurate than the specific tests performed in that instance. I think I shall email those folks and see if they are game for it. They clearly have better funding than I.

The second item in my foodweb amalgam post is concerning a technique used to tell diet of an animal (or person) from samples of bone collagen and hair keratin, using ratios of radioactive carbon and nitrogen isotopes present. The study comes via the recently-moved NCBI-ROFL, and is a test on the extent of the infamous Maneaters of Tsavo horrible diet. The study seems like a proof-of-concept of the technique on a flashy general-interest subject to drum up support (nothing wrong with that). I can also see this technique being used to clear up some things of interest to us folk. Were primitive humans mainly meat-eaters? Was Hitler a vegetarian? And for the vegetarians, it could perhaps verify if the milk and eggs are from animals that were not fed other animals.

23 January 2010

French Stop Testing Oysters on Mice

Oyster photo by Alain Feulvarch
Yes, you read that right. I heard this first on the radio, but there are better text versions here in English and here en français.

The gist is that since oysters are filter-feeders in the big wide ocean, and not raised in a closed system of a farm, and they can pick up pathogens pretty easy. So there are naturally food-safety concerns (ignoring the heavy metals and toxins). So many governments started testing digestive fluid from the oysters by injecting it into mice and seeing if they died (the mouse bioassay, or test de la souris). Very base test. Fast forward a few decades, and most governments find faster, cheaper, more reliable, less cruel ways to test the pathogenicity of oysters. Yet up until recently, France was shelling out money (yuk-yuk) for the old muricidal method. Finally, they have switched to the better-in-almost-every-way chemical test.

Why did this happen? Seems many French oyster farmers were upset that mice oftentimes die even if the oysters were 'clean.' This would mean whole regions of coast would be banned from selling oysters, and many people went bankrupt and so forth. So the oysterfolk complained, and eventually got the change they wanted. I can find no indication that any animal-rights groups were involved (they dropped the ball)

Now I am glad that more mice are living, but upset that perhaps more oysters will die. I am more glad that another unreliable animal test has been ditched in favor of a more reliable cruelty-free test. Though I can not find out precisely which test they are using now, it is a good point to bring up when people tell you that animal testing is 'needed.'