Cochineal Taxonomy Fail

Alas, Starbucks has backpedaled and decided to remove cochineal from all its food and drink products. This is a shame, since as I mentioned a couple of weeks ago, cochineal is an insect-derived dye that provides an important source of cash for a lot of rural Central and South American people. There is also evidence the culture and sale of cochineal leads to more independence and higher female literacy in Mexico. The news coverage of this story is also a shame, because once again the myth that the cochineal insect is a beetle is on the rounds.

Not. A. Beetle.

Not even closely related to a beetle.  In fact, the closest common ancestor shared by a scale insect and a beetle would be around 372 Million Years Ago.

Obviously, as an entomologist, I can be expected to get upset about things like taxonomic mistakes. But for the average news reader, does it really matter that cochineal isn't accurately identified?  I think it does, and that's because the error is one that we would not tolerate, or would mock, if it happened with a vertebrate animal.

Einstein and a chimpLet's say Wikipedia replaced Einstein's photo with that of a chimpanzee. We would immediately recognize this mistake, since chimps are not the same as humans. We last shared a common ancestor 6.4 million years ago.

Alex Wild uses this comparison as the baseline for his calculation of the excellent Taxonomy Fail Index:

A = the actual taxon of the pictured organism
B = the taxon as misidentified
T = the number of million years since A and B shared a common ancestor
H = the number of million years since humans and our closest relatives, the chimps, shared a common ancestor.

Taxonomy Fail Index (TFI) = T/H

In other words, the Taxonomy Fail Index scales the amount of error in absolute time against the error of misidentifying a human with a chimp.

Einstein and a cat So, in my example of Einstein and a chimp, the Taxonomy Fail Index = 1.

Let's look at another example: say Einstein's photo is confused with one of a cat. That error has a Taxonomy Fail Index of 15; over 94 million years separate the common ancestors of humans and kitties.

Using this scale, how big is the error of mistaking a cochineal scale insect for a beetle? That's a Taxonomy Fail Index of 58.

A mistake in classification that large would mean that a photo of a human would have to be replaced with a….FROG.

Einstein and a frog

That is a rather large mistake.

Confusing a highly social placental mammal with a large brain for an amphibian.  An egg laying animal that breeds in water, grows through a tadpole stage, and breathes through its skin.

THAT is why I get really aggravated with the taxonomic mistake of calling a scale insect a beetle.  It is a huge error.   It's not just that I'm being an anal-retentive entomologist that insists that my obscure disciplinary taxonomic language be recognized by all.  (Ok, maybe a little of that. But not only that.)

This sort of taxonomic carelessness is why some really amazing mistakes are made, and leads to news organizations pretty much tossing random photos of any old beetle on their stories. It also leads to misinformation about cochineal itself–this story, for example, mentions "smashed up wings and finely ground tiny legs."  

There won't be any wings or legs in the dye, primarily because the insects are crushed and the pigment extracted. No parts are left behind.  The other main reason is that the dye-producing female insects  don't have wings.  They hardly have any legs, either.

Scale insects don’t undergo complete metamorphosis as a beetle would, so they don’t have larvae and pupae.  In fact, scales have their own special freaky system of growth and reproduction in which the females loose their legs and turn into a sort of tiny insect Jabba the Hutt, and even tinier males fertilize them and die.

News stories like the one I quoted above referring to wings and legs are just feeding the OMGINSECTSINMAIFOODZ freakout.  It's not accurate, and it's sloppy journalism.

Careless sourcing of images on news stories results in lots of Taxonomy Fails; in some cases, it can be a public health issue.  This news article about bed bugs actually had a photo of a flea right above the caption "many people cannot identify bed bugs."  Gosh, you think the fact that incorrect photos are all over the web might have something to do with that?

And now I'm going to stomp off in an entomological huff. Exit stage right.

More information about cochineal and edible insects:


Bug_girl has a PhD in Entomology, and is a pointy-headed former academic living in Ohio. She is obsessed with insects, but otherwise perfectly normal. Really! If you want a daily stream of cool info about bugs, follow her Facebook page or find her on Twitter.

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      1. You're one of those people who insists on Rs B I, amirite?
        BTW, Bug Girl, were you at NECSS?  I did see a water buffalo (or maybe a Gnu, I'm not that good at taxonomy), but no obvious arthropods.  Not even any bedbugs in my hotel.  

  1. This was a really fascinating article, thank you. It astonishes me that the cochineal is being so widely called a beetle by the media, since even Wikipedia doesn't misidentify them. 
    It reminds me of going to the zoo and seeing parents with small children, standing at the tortoise enclosure, with a sign saying "tortoise" right in their face, with a zookeeper giving a lecture about tortoises, and yet they'll turn to their kids and say, "look at the turtle!" 

    1. A few months ago I was in the botanical gardens looking at a sculpture which vaguely resembled a hedgehog or porcupine. A school group was also looking at the sculpture and their teacher asked them what it was a sculpture of. One kid said that it was a hedgehog and then the teacher asked what another name for a hedgehog was. When none of them answered she told them that porcupine is another name for a hedgehog. That is a Taxonomy Fail Index of 15. Porcupines are as closely related to hedgehogs as humans are to cats.

    2. On the other hand, if they are anything like my nieces and nephews, they'll instantly correct the parental units and file this away under "My parents are idiots".

  2. This was really funny. Thanks for writing it since it is great to have a resource where people can hear thoughts from actual scientists. I'm afraid I'm a vegetarian though so no bug dye for me. I really need to be more careful about making sure things don't have meat in them. I never thought my delicious strawberry smoothie would have bug meat in it. (another existential crisis I'm going through is that I've just won a ham. I can't just discard my ham rights like so much garbage, but how can this upstanding vegetarian utilize a ham? Still, solutions will be forthcoming, I'm sure.)
    The middle class outrage is kind of ridiculous though (looking at the petition referenced in the article you linked). Like I can barely afford to get one of those drinks- I'm a vegetarian partly to save money. If you have to get a different flavor it's not some huge affront to your lifestyle.
    I also feel like the "eww bugs" reaction was a pivotal thing in this. It reminds me of the whole "pink slime" thing… apparently people were upset because the meat wouldn't be safe to eat if people hadn't made it safe to eat? That kind of reminds me of all meat. You guys are the ones who eat that stuff!
    It is not such a great sign about society's future if "eww gross" is one of the most powerful social forces for change.
    Oh now I found your other article about this. Coal tar huh? If that's our other choice maybe us vegetarian folk should just stop going to starbucks and use some of the money we save to buy a blender. Protip vegans: almond milk is better than soy milk. Trust me. 
    PS: I think it's really cool that you study bugs. I wanted to do that at one point but then I realized I'd eventually end up hurting the bugs and that would just make me sad. I'm glad there are people like you though.

    1. We went through all that last week.  Don't apologize for being a vegetarian.  It is your right.  I won't mock you for being a privileged rich person who can afford Starbucks and Whole Foods for all their meals, and won't wave strips of bacon under your nose or try to sneak bits of sausage into your vegetable stew if you won't call me a murder or throw paint on my sheepskin hat.  Rational discussion of the pros and cons of veg*anism (is that a wild-card string to replace both veganism and vegetarianism?) and eating bugs and other ewwie things and meat production and factory farms vs traditional farms and coronary artery disease are all fine.  At least, that's my take on the discussion.  Oh, and no straw men, please.
      As for the ham problem, maybe you could replicate a Mythbusters experiment or invent your own?  I noticed they always send Kari to pick up the pig carcasses for ballistics tests, so maybe that's a tradition in science: "Always make the vegetarian provide the dead meat"?  Maybe there's a practial reason, that they won't devour it on the way back to to the lab?

      1. Back on the vegan/vegetarians are all rich thing again?  You guys, as they say "got a bug up your butt"
        As far as cochineal, I get how it's a bummer to lose it economically, considering that people are still eating animals products in starbucks anyways, just from cows and what not.  So yeah, the media's selective outrage machine once again obfuscates the truth.

        1. Sorry if I wasn't clear, but I was trying to snarkily call out the "rich, privileged Starbucks & Whole Foods" meme as a strawman, particularly because panchoruiz was pointing one reason for being a vegetarian is vegetables are cheaper than meat.

          1. hey buzz.
            I wasn't seriously appologizing for being a vegetarian. It is a choice I am really happy with and have been for a long time. I am just saying that I think most of the objections to carmine are not very reasonable and Bug Girl pointed out some of the benefits to using carmine that I agree with. I think it would be nice if I was okay with eating it and I feel a little bad (just a tiny bit!) that I don't want to use it. But like I said, I am okay with my choices/lifestyle.
            Also, I wasn't saying ALL vegetarians or even most are privilaged, stuck up, etc, but when I read the comments of people on that petition I felt alienated from them. I felt like, at least about this one thing, they were behaving in a privilaged/short sighted way and I can't personally relate to someone who feels like whether or not they can drink a starbucks drink is a big deal.

    2. Actually you eat animals all the time. You drink tap water, right? Copepods are common in tap water. The only way to get rid of them is to drink distilled water and that isn't a good idea (it tastes awful, because it tastes like nothing, to say nothing of its effect on your electrolyte balance). Ever eat a red velvet cake? Insects in there too, unless you want to eat unsustainable and probably toxic-in-large-enough amounts artificial colors.
       No, I don't wave bacon under your nose and I don't judge people for being vegetarians. But I ask y'all to choose your words carfully in a discussion about insects :-)

  3. TFI FTW!
    Hope some more examples of this are forthcoming to be held up for our amusement and mockery!
    On a related note, a TV celebrity cook called Luke Nguyen has been popularising fried insects like locusts on TV here in Oz – he reckons they taste just like French Fries!
    OTOH, there was the recent episode of QI where Stephen Fry was all set to gobble some assorted insect lollies but gagged and came over all wobbly after swallowing a candy ant. He remains one of my heroes though.
    Me, I love me some food colouring – dieticians recommend a varied diet after all. Cochineal, tiny legs and all, if present, even better. Synthetic colourings – I ingest bucketloads of Tartrazine and Brilliant Blue FCF with no ill effect. Maybe not for everybody though.
    Did you know that the list of allowable synthetic food colours is different in the US, Europe and OZ and that there is not a single one not banned somwhere in one of the 3 regions? Makes you think.

  4. Good article. It's good to know these things! 
    Though I am sorry to say I'm one of those bad people who is glad when it isn't used in food. Just another thing in the long list of things I am allergic to. :(

  5. Oh, believe me, I know how you feel. Only the other day I saw a quiz qhow in which a question was asked about bees, and they showed a picture of a gorram hoverfly.  I mean, seriously, NO… Just NO.  Flies and bees do not look alike, dammit.

  6. Bug Girl, you might be happy to know that entomophagy is alive and well in San Francisco. The gourmet food truck fad has definitely taken hold here. So much so that there is a food truck devoted to serving food made from bugs. It's called Don Bugito, and a lot of their recipes have a central or south American influence. One of the trendy taquerias in San Francisco has even started serving Don Bugito menu items on Mondays. I will actually be heading over there next Monday to try it out. It will be a first for me.

  7. Since the rate of evolution is not constant, is it really accurate to measure the difference between taxons by the how many years ago they diverged? You could theoretically have have two species that are closely related who diverged about 12 million years ago, but who haven't evolved much, leading to an error index of about 2 despite the mistake not being all that large (though of course still unforgivable). 

    1. Except that "not evolving" is, in fact, evolving. That's a common misconception about evolution.  Even though it may look like a species hasn't changed much, they are still being acted upon by natural selection, and mutating, and experiencing genetic drift. It is evolution that keeps them visibly the same–but they are changing at the molecular level.
      Any organism that "stopped" evolving would be in trouble, since mutations and other random variation would change the genetics of the population very quickly to something sub-optimal.
      As for the technique of molecular dating–

      1. whoops–cut myself off! Molecular clocks:
        Usually they are looking at proteins that are not structural, but functional–cytochrome c, for example.  Different genes change at different rates, so you can cross calibrate your dates.
        All of this is a long way of saying the dates are accepted as fairly solid by most scientists, although they are estimates, of course.

    2. What does the "rate of evolution" actually mean?  The rate of mutations?  That is, actually, relatively constant over a long period of time.
      If you're instead talking about rapid environmental changes, that modifies the perceived rate of natural selection only.  Evolution doesn't stop just because we're not on the precipice of an ice age or asteroid impact.

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