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.
Let’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.
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.
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.
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.)
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 over cochineal. 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:
- Greenfield, Amy Butler. 2005. A Perfect Red: Empire, Espionage, and the Quest for the Color of Desire. HarperCollins Publishers Inc., New York.
- Cochineal: it’s a bug AND a feature
- Are there roaches in your coffee and chocolate? Um. Yes.
- Shellac: It’s a bug AND a feature
- Nutritional value of insects
I can’t remember who pointed this out to me, but it made me laugh. I present: The photo of a “wasp nest” that is actually a mantis ootheca.
Ootheca is a fancy way of saying “egg case.” Both roaches and mantids create egg cases, which is one of the reasons they are sometimes grouped together.
Check out this fascinating video of a mantis creating an egg case. (Interestingly, mantid egg cases are used in Chinese traditional medicine to treat urinary system problems. I have no idea how that connection came about.)
A mantis ootheca is not in any way like a wasp nest. The maximum size is about 1 inch in length (2.5cm). Yellowjacket and hornet nests can get very big–this one was about 6ft by 5 foot.
That’s hardly average–the nests I tend to get on my house seem to be about a foot or so before I clue in they are there–but big enough that using this photo deserves a bit of mockery.
I usually like Lifehacker, but in this case, FAIL. Here’s a story they ran 2 weeks ago:
Bounce Fabric Softener Keeps Mosquitoes and Gnats Away
Some people have sworn by the power of Bounce dryer sheets—and specifically Bounce, too—to keep mosquitoes away from them, and gnats out of their garden. Now scientists have proven the power of fluffy white sheets as an insect repellent.
Lifehacker wasn’t the only media group that picked up on this story; and pretty much all of them made the same mistake.
When you look at the actual research paper, what you see is that some of what was reported was correct. There actually WAS a paper that examined the repellency of Bounce dryer sheets to insects.
Raymond A. Cloyd, et al. (2010). Bounce® Fabric Softener Dryer Sheets Repel Fungus Gnat, Bradysia sp. nr. coprophila (Diptera: Sciaridae), Adults.
HortScience, 45, 1830-1833
There is a very large difference between a fungus gnat and a mosquito. That’s rather like reporting that the care and feeding of cats and humans are interchangeable. Since, you know, we’re all mammals, right?
Let’s start with what a fungus gnat is, and when you’d be likely to encounter them.
Basically, fungus gnats don’t bite. They just annoy. They’re likely to be the tiny things flitting around the soil of your potted plants. They can be a commercial pest in greenhouses, but generally they are just a nuisance. They breed in moist soil and nibble on roots.
I think everyone knows what mosquitoes are–a biting fly that can carry major human diseases. They breed in water and adult females require a blood meal from a host to reproduce.
Not. The. Same.
This is an important difference, and it is a difference that has human health implications. If you go out in an area where there are disease-carrying mosquitoes with just a pocket full of dryer sheets as your protection, you are taking a risk with your health.
Media make mistakes covering science news all the time–but in this case, it’s a taxonomic mistake that could literally cost someone their life. (Ok, I’m overstating it a bit. But, in THEORY, I’m right.)
Now that I’ve impressed upon you what’s at stake, let’s look at the actual experiment, shall we?
The authors tested the repellency of the dryer sheets in a very controlled situation, and were successful at reducing the number of fungus gnats in test chambers containing a dryer sheet. At the end of their paper there is this caveat:
However, there are still important issues that need to be resolved, including the residual effects (based on age of dryer sheets) and effective distance of repellency, response in a no-choice situation (if dryer sheets are placed into each petri dish), impact on fungus gnat larval populations, and ultimately plant damage.
Now, every scientific paper ends this way. Here’s what we did, and here’s how it’s uncovered a whole host of new questions for us to answer! Continued employment, yay!
What I, as a gardener, would draw from this experiment is that it certainly couldn’t hurt to put a Bounce fabric sheet near my potted plants, if I happened to have a fabric sheet laying around.
But I would not, in a bajilion years, jump to the conclusion that it would protect me from all biting insects.
Long link to the paper, since the Researchblogging code keeps messing up blog code
Raymond A. Cloyd, et al. (2010). Bounce® Fabric Softener Dryer Sheets Repel Fungus Gnat, Bradysia sp. nr. coprophila (Diptera: Sciaridae), Adults. HortScience, 45, 1830-1833
I got Bill Bryson’s new book “At Home” from my library, and have been happily reading about the history of houses.
When I got to the chapter “The Drawing Room”, I discovered a rather depressing mistake:
“Shellac is a hard resinous secretion from the Indian lac beetle. Lac beetles emerge in swarms in parts of India at certain times of the year, and their secretions make varnish that is odorless, nontoxic, brilliantly shiny, and highly resistant to scratches and fading.”
Shellac is made from Laccifer lacca, the lac scale. Scale insects look quite different from typical insects. Tiny, with no visible legs or antennae, they kind of look like plant pimples. Like many of their relatives (mealybugs, for example), Lac scales secrete a waxy covering for both protection and waterproofing. That’s what’s harvested to make shellac; it is not a happy process for the insects.
I tried to figure out how Bryson got the wrong end of this taxonomic stick, but wasn’t able to sort it out.
The reference listed in Bryson’s book does correctly identify the insect as a scale; although it also talks about larvae. A lot of internet stories use the name Coccus lacca, or suggest that it’s an insect that has a pupa and full metabolism.
Scale insects don’t undergo complete metamorphosis, 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.
Clearly, there is a need for a short epistle on Shellac, it’s insecty creators, and its many uses! (including your food!)
Look for it soon!
[image from Project Gutenberg]