What is a phoretic mite? As many of you know, I am passionate about words. Words are meant to convey meaning, and the right word allows us to communicate with clarity and brevity. On the other hand, sloppy vocabulary leads to mushy thinking.
Part of the reason ten beekeepers give fifteen different answers to the same question is the lack of standardized vocabulary. The use of inaccurate terms makes the listener think he is hearing more answers than he actually is.
The vocabulary of beekeeping
I have written many posts about the vocabulary of beekeeping, and I try to remain consistent within my posts and in my answers to questions. Sometimes though, especially when I’m tired, I write bad things that need to be deleted. For example, when someone recently explained that their hive swarmed into a tree, I wrote, “That’s amazing! And what about the bees? Where did they go?” Delete.
Of course, I understood what she meant, but it was imprecise. Most bee books will tell you a hive is a man-made structure designed to house managed honey bees. It doesn’t fly away. It doesn’t starve. And if you like to verb your nouns, you can hive a colony or you can hive a swarm, but you can’t hive a hive. So why go there?
Are phoretic mites really phoretic?
By now you’re probably wondering what this tirade has to do with phoretic mites. Well, another beekeeper asked a great question. She said that the word “phoretic” implies a symbiotic relationship, but she has never heard of any benefit to bees from having mites. Hmm.
A phoretic mite is simply a mite that attaches itself to an adult bee. It is an easy way for the mite to move around on the inside of the hive, and it can jump off whenever it pleases. Likewise, a phoretic mite can ride to a place outside of the hive. It can land on a flower, for example, where it can wait for a connecting flight. Some lucky mites ride on a robbing bee or a drifting bee and end up in a completely different hive.
One of the books on my shelf, A Dictionary of Ecology, Evolution and Systematics (Cambridge University Press) defines phoresy as “a symbiosis in which one organism is merely transported on the body of an individual of a different species.” After reading that, I was pretty sure that phoretic was the wrong word because even if phoretic mites are simply riding on adult bees (and not feeding) they are still basically parasites. Furthermore, I didn’t know for sure whether the mites were feeding while they rode or not.
So I asked Katie Lee of Bee Informed Partnership, a mite specialist. She suspects phoretic mites do feed on their rides. Since adult mites can overwinter in a hive even when brood are not present, they must be feeding on something, and that something is most likely adult bees.
After hearing from Katie, I was ready to declare that phoresy was the wrong word because the mites are not merely being transported at that stage, they are probably getting fed.
Obsessing over the wrong word
But then I changed my mind again. An entry in Wikipedia tells us that “The definition of symbiosis has varied among scientists. Some believe symbiosis should only refer to persistent mutualisms, while others believe it should apply to any type of persistent biological interaction (in other words mutualistic, commensalistic, or parasitic). After 130 years of debate, current biology and ecology textbooks now use the latter definition or an even broader definition (where symbiosis means all species interactions), with the restrictive definition (where symbiosis means mutualism only) no longer used.”
That is certainly different than the definition I learned in school, but if the standard definition has changed, then so must I. One more check sent me back to The Dictionary of Ecology, Evolution and Systematics. It defines symbiosis as, “The living together of two organisms; the relationship between two interacting organisms or populations, commonly used to describe all relationships between members of two different species, and also to include intraspecific associations, sometimes restricted to those associations that are mutually beneficial.”
The key phrase here is “sometimes restricted to those associations that are mutually beneficial.” In other words, sometimes it’s not.
Full circle back to the right word
So in just a few days I went full circle from thinking phoretic is the right word, to thinking it is the wrong word, and back to thinking it’s probably right. But during that journey, I developed a picture of current scientific thought on symbiotic relationships which helps me understand and explain science to others.
As scientific beekeepers, we must be sure of our vocabulary before we make statements that may confuse rather than illuminate. In this case, I was concentrating on the word “phoresy,” all the while assuming I knew the meaning of “symbiosis,” but it was the word “symbiosis” that had evolved while I wasn’t paying attention. Lesson learned.
Honey Bee Suite