Beekeeping Today Podcast - Presented by Betterbee
Feb. 12, 2024

Drones and Purdue's Harpur Lab with Dr. Brock Harpur (S6, E35)

(#264) In this week’s episode, we explore into the fascinating world of drones with Dr. Brock Harpur from Purdue University. Listen and discover the critical role drones play in bee colony health and how current research is challenging previous...

Dr. Brock Harpur(#264) In this week’s episode, we explore into the fascinating world of drones with Dr. Brock Harpur from Purdue University. Listen and discover the critical role drones play in bee colony health and how current research is challenging previous misconceptions about these maligned members of the hive.

Dr. Harpur shares his journey from a studious kid in Northern British Columbia to leading groundbreaking research in bee genetics and evolutionary biology. Learn about the innovative projects underway at the Harpur Lab, including a deep dive into drone nutrition and the quest for understanding the genetic diversity among drones.

This episode is a treasure trove of insights for beekeepers eager to deepen their knowledge and improve their beekeeping practices.

Featured Topics Include:

  • Dr. Harpur's personal journey into bee research.
  • The underestimated importance of drones in bee colonies.
  • The Harpur Lab's cutting-edge drone research projects.
  • The potential impact of drone nutrition and genetics on beekeeping.

Links and websites mentioned in this episode:

Leave comments and questions in the Comments Section of the episode's website.

 

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This episode is brought to you by Global Patties! Global offers a variety of standard and custom patties. Visit them today at http://globalpatties.com and let them know you appreciate them sponsoring this episode! 

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Thank you for listening! 

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Beekeeping Today Podcast is an audio production of Growing Planet Media, LLC

Copyright © 2024 by Growing Planet Media, LLC

Transcript

 

S6, E35 - Drones and Purdue's Harpur Lab with Dr. Brock Harpur

 

Brian: Hello, this is Brian.

Kathy: This is Kathy and we're from Baker Bees-

Brian: -in Pride, Louisiana.

Kathy: Welcome to  Beekeeping Today Podcast.

Jeff Ott: Welcome to  Beekeeping Today Podcast presented by Betterbee, your source for beekeeping news, information, and entertainment. I'm Jeff Ott.

Becky Masterman: I'm Becky Masterman.

Global Patties: Today's episode is brought to you by the bee nutrition superheroes at Global Patties. Family-operated and buzzing with passion, Global Patties crafts protein-packed patties that'll turn your hives into powerhouse production. Picture this. Strong colonies, booming brood, and honey flowing like a sweet river. It's super protein for your bees and they love it. Check out their buffet of patties tailor-made for your bees in your specific area. Head over to www.globalpatties.com and give your bees the nutrition they deserve.

Jeff: Hey, a quick shout-out to all of our sponsors whose support allows us to bring you this podcast each week without resorting to a fee-based subscription. We don't want that and we know you don't either. Be sure to check out all of our content on the website. There, you can read up on all of our guests, read our blog on the various aspects and observations about beekeeping, search for Download, and listen to over 250 past episodes, read episode transcripts, leave comments and feedback on each episode, and check on podcast specials from our sponsors. You can find it all at www.beekeepingtodaypodcast.com. Thank you, Brian and Kathy from Baker Bees. They're in Louisiana.

Becky: Pride, Louisiana.

Jeff: Pride, Louisiana. Fantastic. I remember meeting them at the NAHBE show. Great opening. Becky, for the next couple of weeks, we do have many guests that stop by at our booth in Louisville at the North American Honey Bee Expo to talk to us, so look forward to that.

Becky: I can't wait. I love hearing every opening that the listeners do for us. Since you're not sharing them with me ahead of time, I'm just going to be in anticipation for the next one.

Jeff: I like being like Santa Claus, surprising everyone.

Becky: Is there a Minnesota in the group, Jeff?

Jeff: No Minnesota in the group.

Becky: [laughs]

Jeff: I will tell you that right now.

[laughter]

Becky: You could have just teased me a little bit. [chuckles] Come on, Minnesota. [laughs]

Jeff: Maybe someone from Minnesota will jump up and contribute here. Well, we do have a very busy month. Finally, through January is a long month. Always is. This month, people are starting to think about bees. I know people are combing through the catalog. I'm sure they've got their Betterbee catalog out there buying stuff from Betterbee.

Becky: Marking their new technology that they need or maybe their new deeps because they're going to get more colonies this year.

Jeff: Honey supers, thinking ahead, planning ahead.

Becky: There you go, or they're taking classes because 'tis the season to learn how to become a beekeeper.

Jeff: Check out your local club, your association. There's online courses. Betterbee, of course. It's a busy month. People are starting to think about that. Do check out our sponsors. Buy books. Buy books from Northern Bee Books.

Becky: Northern Bee Books. If you want to learn how to make more honey, if you want to learn how to fight Varroa, search their site because you're going to find lots of opportunities to become a better beekeeper.

Jeff: Also, we got Strong Microbials. You want to get your bee's gut healthy with the probiotics and Global Patties. Stop by the sponsors, let them know you listen, and buy their products. Enough for the unpaid advertisement there, Becky.

[laughter]

Becky: I was going to launch into bee nutrition, but I'll stop right there. Hey, can we advertise what we're doing as far as instruction? Do we have to pay for our own blog?

Jeff: We're paying for it. Believe me.

Becky: Okay.

[laughter]

Becky: I'm excited because we've been working hard at putting together a new, I guess, series of getting started in bees to go with the old series. We've been putting together some great information for brand-new beekeepers and also beekeepers who want a refresher or to get some good ideas.

Jeff: It is an exciting series we're building back in what I believe 2020 when Kim, Jim, and I did the original  How to Get Started series. We couldn't cover everything we really wanted to. We're just updating and adding to that content. We're not replacing it. This is just additional chapters in that book of information. It's been fun to prepare.

Becky: It's exciting, yes. I think that listeners are going to be happy to listen, to share, and further their beekeeping talents by downloading the episodes as soon as they're ready. How many more weeks do we have, Jeff?

Jeff: They start releasing on February 19th. It would be  How to Get Started, Part 1A. I'm not sure how we're going to name them, but it's the second part one, and then the 26th and then we move into March, the first two Mondays in March, which are the 4th and the 11th if I have the dates right. It's going to be a fun series. We hope our listeners enjoy it. Also, I wanted to mention that later in April, April 13th, Kathy Summers is holding a memorial for Kim Flottum in Medina, Ohio. If anybody wants to participate or attend Kim's memorial, you can find additional information on our website, and that link will be in the show notes.

Becky: Today, we have another agenda item and that's that we get to talk about drones with Dr. Brock Harpur from Purdue. Are you all set for all your drone questions?

Jeff: I am. Drones are so maligned in the bee world. If we were to have the cartoonist draw us a picture of a drone, he'd probably be standing there with his legs crossed, leaning against the wall, smoking a cigarette.

Becky: He would for sure be smoking.

Jeff: Yes.

[laughter]

Becky: He'd have a drink in his hand too. A big old drink of nectar.

Jeff: In one of his hands and asking for more from a passing worker bee. They're finding in the research that that's not quite correct, that they're very important for the homeostasis of the healthy colonies. They have the right number of drones in the colony. I'm looking forward to talking to Brock, find out what he's finding out.

Becky: Yes, I'm a little worried because every time I give a talk, if I talk about drones, I have a couple of really good jokes I get to tell. They're so much fun to make fun of. I might have to change my talks and give them a little bit more respect than what I am currently delivering.

Jeff: Are these jokes for prime time? Are they podcast jokes?

Becky: Well, it's nice to have my slide deck up because it's part of the delivery, so you have to see it. It's a different medium.

Jeff: Understood.

Becky: Yes, prime time. I've yet to be banned by a club because of inappropriate talk of drones. [laughs]

Jeff: All right. Hey, we'll be hearing from Brock in just a few moments. First, a quick word from our friends at Strong Microbials.

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Jeff: While you're at the Strong Microbials site, make sure you click on and subscribe to  The Hive, the regular newsletter full of interesting beekeeping facts and product updates. Hey, everybody, welcome back. Sitting across this virtual  Beekeeping Today Podcast table is Dr. Brock Harpur. Brock manages the Harpur lab there at Purdue University. This has been a rough start, Brock. Thank you for joining us on  Beekeeping Today Podcast.

Dr. Brock Harpur: Yes, no problem. Happy to be here. Thanks for having me.

Becky: Welcome, Brock. We're so happy you joined us.

Jeff: You're out there in Indiana managing the bee lab. You're doing a lot of work. Before we get into everything you're doing, can you give us a little bit about your background, your beginning story, if you will, of how you got started with bees and ended up here?

Brock: I've been here at Purdue for five years in my role as an assistant professor. I, before that, was in Canada. I was in Toronto for about 10 years. Then before that, Northern British Columbia, a small town called Prince George. A smallish town, I guess. That's where I started really getting into bees. I was a very bookish kid. I liked to read, but I also liked to hike. There wasn't much more to do in the town that I grew up in.

That worked out very nicely for me. I really liked biology. It turned out I was pretty good at it because I just like reading and hiking and looking at things outside. I was told when I was young that if you like biology, you should become a medical doctor. I went down the road of becoming a medical doctor. I was pre-med. Grades were pretty good, but I really just didn't like-- I hope none of them are listening to this. I didn't like the people.

[laughter]

Brock: I'm sorry if you're one of the people listening, but no.

[laughter]

Brock: I wanted to go on hikes and look at things in the woods and talk about evolution and genetics. Everyone else was more interested in grades and stuff. That wasn't me. I was having a bit of a panic, thinking what I wanted to do. Someone took me out beekeeping. A very close friend named Gerry Bomford took me out beekeeping. I instantly fell in love as soon as I-- not with him, with the bees.

Becky: [laughs]

Brock: He opened up my first colony. I just remember just a cacophony of sound and smell and everything. In fact, every time I now smell cigarette smoke and honey together, I think of that day because Gerry was one who used cigarette smoke as his smoker.

[laughter]

Brock: It stuck with me. I just always remembered that moment and thought, "Well, maybe if I'm lucky, this can be a career in biology in some sense." I switched from pre-medicine to biology with not really much of an idea in mind other than I liked bees. After that, I was a beekeeper during that time. Gerry trained me. He taught me everything I know. I've been a beekeeper since-- well, I won't say the year, but since a long time ago when I was an undergraduate.

I kept up with it. I kept pushing into research. I worked in a cancer lab for a little bit. I worked in a genetics lab and I worked in an ant lab. Eventually, I landed as a PhD student in Toronto, where I started doing some work on evolutionary biology and honeybees all the while being a beekeeper, but that's how I got into it. A failed medical student became a bee-obsessed person and here I am.

Jeff: Oh, that's great. I will not be able to think of anything else today other than Chesterfield-infused honey.

Brock: [laughs] It's a really unique smell and it doesn't happen very often. Not a lot of people smoke anymore and I don't see beekeepers using cigarette smoke as their smoker. When I get those two together, it's very special.

Jeff: What is the Harpur lab doing? What's the main focus there?

Brock: I am a trained evolutionary biologist, which means I'm interested in what makes different populations or different species different from each other and whether or not those differences are the result of selection or drift, which is all, I guess, technical, but I apply that to honeybees. I'm very interested in understanding why different populations of bees might produce more honey, be more defensive, have a different color than each other, and how epigenetics contributes to that. That's the primary focus of our lab. I train my students to think like evolutionary biologists. We really do a lot of techniques now. We've expanded a lot. Primarily, our main tool is genetics.

Becky: You're looking at honeybees, but before we get more into the honeybees, you're also looking at a lot of other different organisms. Anything that has social behavior that's an insect, it looks like it has sparked your interest too.

Brock: Yes, we study a few others. Honeybees are still my primary love, but there are some cases where other social insects or social species are doing things that are just fun to look at or to consider and some cases where those social insects could impact honeybees. We have some work on the northern giant hornet in the lab right now. That's the one that was found in Nanaimo, Canada and Washington State. We're doing some of the genetics on that to try and find out where it came from, how likely it is to persist.

We were doing some genetic work with the northern giant hornet. We also have some work with some Argentine ants, another invasive species where we're looking at how they determine nestmate identity among each other. All social insects are able to identify nestmates from non-nestmates. We know a lot about how honeybees do that, less so about other organisms. I have one graduate student who's working on Argentine ants and he's trying to find the genes and neurons responsible for nestmate recognition.

Jeff: How do the honeybees determine nestmates?

Brock: Yes, really good question. It all comes down to smell. We'll talk about workers, I guess, primarily. When a worker emerges from her cell, she has a scent about her. She picked up from the wax and pollen as she was developing. The smell is made up of what we call cuticular hydrocarbons. They're just like little waxy, oily molecules that get made by and then picked up by as well the body. Bees are a little waxy. For the first few days of her life, her and all of the bees that emerged at about the same time, they all smell the same.

As they begin moving and roaming about the colony, developing, maturing a little bit more, they also pick up additional smells from the colony, either by rubbing up against individuals or just from the food they're eating and what they're digesting. After those few days, they smell approximately like every other bee in the colony. It's called a gestalt smell. Workers will essentially detect those waxy, smelly compounds with their antennae. I'm making little antennae with my fingers. I know.

[laughter]

Jeff: That was very accurate, by the way.

Becky: They look exactly like antennae. [laughs]

Brock: They touch their body with antennae and they can detect pretty quickly whether or not a bee is a nestmate or not.

Jeff: Well, this leads to a question we might want to talk about later when we talk about drones, but how is it that the drones are accepted in multiple different hives?

Brock: Yes, that's a question others have looked at. It looks like they're probably able to tell a nestmate drone from a non-nestmate drone based on one study, but they almost just don't care. The reason they don't care, at least that-- We're going to call this a just-so story because no one's actually tested this rigorously. The just-so story, the reason that we think this is the case is that wild colonies in their wild landscape don't really care so much if a foreign drone enters because it's not going to alert its nest or, pardon me, its colony that there's food resources elsewhere.

It's not going to do anything necessarily bad. It's also incredibly rare for a drone to drift to another colony in the wild. They're separated by quite a long distance in the wild. The pressure for a worker to tell a nestmate drone from a non-nestmate drone is pretty low like the evolutionary pressure versus a worker. If a worker from another colony finds your colony, that can lead to robbing. There's pretty strong evolutionary pressure for them to be able to detect nestmate from non-nestmate. Again, all of that is a little handwavy just so it makes sense, but no one's ever tested it. It'd be a hard thing, I think, to test, but it would be fun to do. Yes, that's essentially it.

Becky: You're showing us your evolutionary biologist muscle for that answer, though, so thank you. [laughs] We tell beekeepers that those drones drift as long as the nectar flow is on. As soon as they decide that they're going to not allow their own drones in, then they start to discriminate.

Brock: Right. A lot of the decision on the colony for drones comes down to resource availability. Drones will be evicted when resources are low. You tend to see that obviously in the fall, at least the fall here in Indiana. Resource scarcity will tend to push drones out. If those drones can find another colony that accepts them, they'll go there. Drones get kicked out because of resource availability. If you're a bee breeder out there and you mark your drones in different colonies, you might notice that they just tend to drift if you have colonies of high density anyway. The stat that I quite like is in any given colony during peak drone season, 50% of the drones inside won't be from that colony in a typical apiary operation.

Becky: Okay, there are a lot of jokes we could just go with right now if we wanted to. Thank you.

Jeff: On that note, let's take a quick break and hear from our friends at Betterbee.

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Becky: Brock, I know one person in your lab, a recent graduate, Garett Slater, who's been working on drones, but you mentioned that you have five different drone projects going on in your lab right now. Can you name them all in five minutes? No, I'm kidding about that.

[laughter]

Becky: Could you share with the listeners what you're doing with drones? Because I think they're going to be excited to hear it.

Brock: Garett kicked off a lot of the work on drones in the lab before he finished up and is now a successful postdoc with the USDA, but we've continued some of it and elaborated on it a little bit. I think it's about five projects on general drone biology right now. Drones are understudied. That's just because of really what scientists in my field have been interested in with honeybees.

They're interested in the workings of this society that is mostly made up of workers. All the fun behaviors, of course, are done by workers. The fun differentiation of sexes between queen and worker is pretty fascinating to biologists. Drones haven't really been looked at a lot and I think that's too bad. [chuckles] I think there's a lot of fascinating biology there. A lot of our work focusing on drones is trying to understand variants in their traits across populations.

We look at things like what makes different populations of drones produce more or less sperm, what causes different colors on their body, or-- actually, we have a fun project on eye coloration right now, and what makes drones different from workers. I'm excited about all the projects, but the ones that have been really fun recently to work on, one by my graduate student, Jonathan Nixon, has been looking at drone food. You'd think we'd know what drones eat, but we don't. [laughs]

Jeff: It's interesting because all the beginning beekeeping courses all say, "Well, the workers feed them a honey mixture."

Brock: Yes.

Jeff: That's it. [laughs]

Brock: It's probably very similar to what workers get. When I say "eat," I mean as larva, right?

Becky: Are you going to say larvae or adult?

Brock: Yes. As larva, they are fed. They're provisioned by workers. We've all seen this if you've opened up a colony and peeked into your drone frames, but we don't actually know the composition of that food. We don't know how different it is from workers. We think that it should probably be different. Drones take longer to develop. There's a few extra developmental days. A few of those days, especially about day five, they're producing sperm. Sperm is really expensive to make. I hope I can say "sperm" on here. You said "Disney," and I'm sure Disney would have a sperm movie, so we're good to say that. [laughs]

Jeff: Okay.

[laughter]

Becky: No, we're keeping that in.

[laughter]

Brock: I'll cut back. On day five, that's when they're making sperm. They only do it once in their entire lifespan. That is it. They get one shot at making it. It's pretty important for them at that point to probably have a lot of protein in their diet and to probably be developmentally stable, right? The workers are probably going to make sure that they're not experiencing any neglect during that pretty critical time period.

Jeff: You said day five. Is that day five as a larva or day five as an adult?

Brock: Larva.

Jeff: Okay.

Brock: Yes, so it's just before they pupate like just before they get the cap on top. I should actually add. The food itself, we know there's probably honey in there. We know there's pollen in there. At least by eye, you can see that as drones are fed progressively, it just gets more and more rich with pollen. We know there's royal jelly, but we don't really know chemical identities. We don't know amounts. I missed one other thing too. There's also bacteria and fungi and yeast and all kinds of other fun, little microbiome components in there.

My graduate student, Jonathan, he set up colonies that made drones and workers at the same time. He collected the food that they were eating every day from egg until just before pupation and he collected the larva. What we're doing with that is we're using a few different techniques to compare drone to worker and then compare day to day. We're using NMR if you're familiar with that kind of technology. Oh, it's my favorite crime show now. If you've watched  NCIS, you've seen them use an NMR. I can tell you, it takes a lot longer than a 30-minute episode.

[laughter]

Brock: We're actively looking at those traces that you get from NMR and trying to figure out what chemical compounds differ between the two and how they change through time. We are also doing some microbiome work to see how that changes through time. We collected the larva so that we can look at how physiologically the larva change every day. We're hoping to link all of those three things up. The goal is really just general basic biology to understand the differences.

Some of the applications include finally having like an in vitro diet that works for drones. If a beekeeper has done this, please email me. I doubt you have, but I would love to know. If you have fed workers in vitro like in a little incubator, there's a diet, a standard diet that one can feed workers. There isn't one for drones. If you try feeding the worker diet to drones, it doesn't tend to work as well. We'd like to figure out a diet for drones as well. That project's been super fun.

Becky: When you say it doesn't work, does that mean there's high mortality or--

Brock: They don't tend to survive as well as they should.

Becky: You're looking for the key to drone life right now.

Brock: That's a cool way to put it.

Becky: You're going to identify it.

Brock: Can you write my branch for me?

[laughter]

Brock: That's a really good one.

Jeff: I would suspect that part of this would have to have some impact by Varroa.

Brock: Yes, that's right. We would almost certainly predict that-- well, we know Varroa infestation impacts drone like later-in-life drone reproductive success sometimes. Once we know the diet and what they're getting, we can start looking a little more deeply about how variation to what they're getting as a result of just feeding or what Varroa takes from them via their hemolymph. Once we know a little bit more about the basics that we can begin expanding and asking how variation in those basics impacts reproduction. Anything that hits them on that fifth day is probably going to impact sperm in some way, their ability to reproduce.

Jeff: If the drones are used for the insemination of queens and they're donating sperm to the insemination process, that really impacts everything.

Brock: That's exactly right. Queen failure can occur because of poor mating. If she's mated with the drone that has too little sperm or sperm that is of low quality, her laying success is going to be low and she will likely be turned over. That's a huge topic in the literature right now. There's some fantastic work on the queen's side of this picture, understanding how queens have to store and keep that sperm safe. We're more interested in the drone side, the one that produces the sperm.

The big question for us is, one, was just we didn't understand the nutritional differences. Garett made these wonderful common gardens of these different breeds. We were able to identify genes and genetic networks that contribute to variation in sperm quality. We actually know there's a genetic component to this. Different breeds like Italian, Carniolan, et cetera, they are different in how much sperm they produce and the quality of that sperm. We're hoping to get that published this year. That was a very fun study. We've got genetic component. We've got nutritional component. We think together should greatly enhance our understanding of just basic drone biology.

Jeff: Did Garett also look at the Africanized bee too, honeybee?

Brock: We're not allowed to keep or work with that bee here in Indiana. We didn't really have the resources to go down to Texas and work with it. We did have bees that had scutellata in them, but they weren't the killer bee.

Jeff: It'd be interesting to add that into the mix as well at some point.

Brock: Yes, I think Texas is a great place to be able to do a study like that where you have both. You have the bees from California and the bees-- well, not just from California. California is another great place to do it because you have both genotypes, but Texas, California, Arizona, any place where you can work with both would be a great place to do a study like that.

Becky: Can I ask a really technical question?

Brock: Yes, please.

Becky: Worker bee nutrition was well understood. When you decided to go ahead and develop methods to study the drone nutrition, did you use original methods that were used for the worker information that was gathered? If so, what iteration of that? Because I know that people have studied nutrition. It was just early on that people really dug in and studied nutrition, but what version are you using? Is it an updated one? Does that make sense? Because you have to be more sensitive now.

Brock: Yes, so we picked NMR because that can give us an idea of all of the chemicals in the food. We used some modern microbiomics as well that hasn't really actually been performed on any of the food. I think that's correct. I got to go back and check, but I'm pretty sure that hasn't been performed on worker food. It certainly hasn't been performed on drone food. We used the modern techniques that were available to us. We used modern techniques that are available to us and then we used a technique that we can compare across different data sets as well.

We can compare back to some of those older worker data sets. As you said, folks have been looking at worker nutrition for quite some time and with very different types of tools. There's some very old-ish studies from the '50s and '60s where folks used bomb calorimetry to identify just how many calories are in the food. There are some newer ones where they looked at proportions of nitrogen versus carbon or protein versus carbohydrate in food. We didn't use those techniques because we had an NMR available to us.

[laughter]

Becky: Are you updating the worker nutrition information too at the same time?

Brock: Yes, I think we'll be able to update it a little bit, but we wanted to have the worker component in there as a comparison to the drone. As I mentioned, if you use a worker diet on a drone, the rearing success isn't usually as high. We knew or we posited that there's probably a difference in the chemical compositions of the two. That's why we had worker. It was just to make that comparison.

Becky: You are working with queen breeders?

Brock: Yes. One of the advantages of what we do in understanding differences between populations from a genetic perspective is we can apply that to breeding. I was trained in genomics and genetics. Genomics has revolutionized animal breeding many, many, many thousands. If I'm not wrong, I think over a million cows have been genotyped in this country, or at least in the world, I should say.

By having that data, you can begin to predict future phenotype. It's a way to increase our predictions of how animals should perform. It's a way for us to, I guess, gain a more deeper understanding of the organisms we're working with. In addition to just phenotypic prediction, you could do some other stuff as well. If you know that there are genetic variants that differ between populations, you can use genetics to tell where an unknown sample is from, right?

If you two send me bees from your yard, I can sequence them and say, "Well, you shouldn't keep this one." This is from that line that we're not allowed to keep in your state. This one here, this is an Italian. You probably got it from Georgia, California, or somewhere. [laughs] We can actually add some information back to our breeding efforts. We do work with bee breeders. We have a project right now with the Indiana Queen Breeders Association, where we are actively using genetic information to predict phenotypes in the next generation.

We've sequenced the genomes of many, many workers from all of the bees in one of these large breeders' yards. We've tracked them for a season. My wonderful graduate student, Dylan Ryals, put in just months of effort tracking these colonies and making sure they're queenright and gathering phenotypic data from them. We have used that along with the pedigrees that the bee breeders had and some genetics to begin predicting phenotypes, so predicting essentially which colonies that that bee breeder should be selecting in the next generation.

Becky: I love bringing technology in to support the beekeepers. They've been doing it with their eyes for such a long time.

Brock: What's actually been fun about this project other than just the technology use of it is how highly correlated our estimates are with the beekeepers.

[laughter]

Brock: We did this in a way in which we gathered all the data and then the beekeeper/bee breeder worked with their colonies for the whole season. At the end, we said, "Okay. Well, which ones would you pick as your top breeders?" He gave his list. We gave our list. They were very, very similar. The differences are where we were interested, but they were very, very simple.

Becky: Are you working on any genetic lines in your lab?

Brock: Yes, so I inherited the mite biter system from my predecessor, Greg Hunt, and Krispn Given is Purdue's senior apicultural specialist. He's still here and he still maintains the line. We do have the Indiana mite biter that we work with here. That is a line of bees that was developed by Krispn and Greg that expresses a mite-resistance trait. The bees, they bite the legs off of Varroa mites.

It's neat to see. [laughs] We do grooming assays. You put a sticky board in the bottom of the colonies and you pull it out. You look at the Varroa mites underneath. You count them and you look at them. In our mite biters, we see a lot of Varroa mites with damage to their body. That's essentially what the phenotype is. We have the mite biter here. It's still going. It's still actively being maintained. We work with the Indiana Queen Breeders Association to keep that line available to beekeepers.

Jeff: How long does a trait like that stay in a population?

Brock: We've had it here for 17 years, but is there context to that question?

Jeff: Yes, if I was to buy five of those queens, only as long as that queen was in my hive, would they exhibit that trait or would her daughter's queens express that trait as well?

Brock: Based on our look, the daughters would express it too. I guess the important way to look at this is that every generation where you're not maintaining the selective effort, you're going to potentially lose that phenotype. If that trait is not present in your populations at all and you're not maintaining it, you're not selecting on it, you're not keeping that phenotyping up, then, eventually, you will probably lose it. If you're not controlling matings in some way, then, eventually you might lose it. You're asking about lines that we have. We have that one going. We had one that I was very keen on keeping alive. Unfortunately, it passed away this season. We had a white-eye-producing colony. Have you ever seen a white-eyed drone?

Becky: Oh, my gosh, yes. [laughs] I love that. Of no use to beekeeping whatsoever. [laughs]

Brock: It's not at all, but it's very fascinating in terms of biology. Ever since I started beekeeping way back when I was an undergraduate, I was also doing genetics at the same time. I thought, "Well, are there any fun genetics papers on honeybees?" There are dozens and there are hundreds. The bee geneticists from the 1920s until now have just been really fascinating with what they've been doing. The early stuff is great because they didn't have genome sequencing.

They just only had these mutations that they could look at. There are just dozens of papers describing various eye and wing and body mutations that bee geneticists found. I grew up in the age of genomics in the post-honeybee genome era. I thought, "Well, wouldn't it be fun one day to try and find the genes for this?" I wrote that down actually in a notebook. Anyway, here I am where I'm a bee geneticist. Someone emails me. A beekeeper emails me and says, "I have a colony producing white-eyed drones." I said, "I'll buy it."

[laughter]

Brock: We had one going. We did many, many studies on that colony. We hope to keep it going. Unfortunately, none of our grafts inherited the trait. We lost it, but we're putting together a study now where we've identified the gene responsible. We did some phenotypic work on them as well. We actually subjected the drones to different tests to find out if they're blind and what they see, what they don't see, the morphology of their eye. We did quite a lot of work to try and figure out what this mutation does. It wasn't just our lab. It was a collaborative effort from many of the bee scientists across the country and even in Canada because everyone I emailed when I said I have a white-eyed drone had the same reaction that you had, Becky.

[laughter]

Brock: They're like, "Of course, yes, I want to work on that." Yes, we have a pretty fun study coming out this year as well.

Becky: That's so cool. When you moved from Canada beekeeping to United States beekeeping, did you see some major differences?

Brock: I have worked in very different beekeeping environments. In Northern Canada, we had about four months of beekeeping and then eight months keeping our colonies alive through the winter because I'm from very far north. Then I moved to Toronto where I didn't own land, so I rented. I was doing rooftop and condo beekeeping. I had one apartment where I had a balcony that was probably-- I don't know. It was 2 feet by 6 or 12-foot square. I had a colony on there while I was living there. My neighbors never found out luckily. I did some urban beekeeping, which is a very, very different thing than most beekeepers are used to.

In Toronto, I should say the environment is similar to where I am in Indiana in terms of the seasons that we get. It's a little harder in urban to make sure that you're getting consistent nectar flows. Otherwise, weather-wise, it's very similar. How we handle the colonies is very similar to here in Indiana. The scale is different. I went from urban as a grad student, so I wasn't a huge beekeeper. Now, we have 200 colonies to manage. Luckily, Krispn Given is here to help with that. I guess in terms of management, it hasn't changed a lot.

Jeff: Brock, is there anything that you'd like to talk to us about that you want to describe?

Brock: How time flew.

Jeff: Yes, time. I told you, it goes quickly.

Brock: [laughs] I think we covered all of it. There's always more work that we're doing in the lab that I'd love to talk about, but I don't want to take 45 more minutes of your time. Have me back. Have my graduate students back.

Jeff: I'd like to talk more about the drones at some point because I still think they're understudied and underrepresented in the literature.

Brock: We've been having quite a lot of fun working with drones. They're not easy to work with. They're very fragile, [laughs] but there are so much more fascinating biology that we haven't understood yet about or gained an understanding of in drones. What we have found so far, we think, will empower the beekeeping community, at least a little bit. I guess if I were to add anything, I've talked about all the genetics that we can do and working with bee breeders. We do offer genome sequencing services to beekeepers.

I won't sequence your genome, but I'll sequence your bees' genomes. It's relatively inexpensive. It's $85 a sample. We sequence it and we tell you where your bee came from. Then your sample gets added to our database that is ever growing across the country. I think we've got over 2,000 samples now. If you're curious to know where your bees are from, whether they're Italian, Carniolan, and Russian, et cetera, we can tell you that if you're interested. That's it. If you type in "Purdue honeybee genome sequencing," you'll find it.

Jeff: Is there a map available with the results?

Brock: Yes, so there will be. We're putting together a map of the overall results for publication. Right now, we've hit pretty much every state. We're still a little low in Nevada, Idaho, could use some more from Louisiana. Honestly, we'll take samples from anywhere at this point.

Jeff: Very cool. Brock, it's been a great pleasure having you on the show and look forward to having you back on a regular basis.

Brock: [chuckles] Sure thing. Yes, it'll be great.

Becky: Thank you, Brock.

Brock: Take care.

[music]

Jeff: Brock was more entertaining than I had even hoped. I knew he was fun just based on our correspondence, but it was enjoyable to have him on the show.

Becky: He just delivered. I think that when a guest, you can't wait to have them back, which is, honestly, a lot of our guests. I think that's just such a treat. He's doing great things and he's going to do more. He's just at the beginning of his career.

Jeff: It's impressive. Go out to his website and we'll put the link in the show notes to look at the work they're working on at the Harpur bee lab. Not to keep stating this, but the work they're doing on drones, just not seeing it anywhere else. I find that fascinating. This is why I'm doing a podcast and not running the bee lab, but I had never considered that workers are feeding the drones a different food than everything else. Everything we've always learned is that, well, basically, the workers feed the drones and they grow up to be males and blah, blah, blah, and that's it. It's interesting.

Becky: It reminds me a little bit of Sammy Ramsey in his pursuit of his PhD where he was answering a question that hadn't officially been asked before as far as what Varroa are feeding on. It seems like Brock has a really just comprehensive line of research projects that are going to give you that information that you want to hear about drones. Only interesting things are going to come out of this work.

Jeff: I agree. I look forward to having him back.

Becky: Absolutely. Let's get him booked.

Jeff: That about wraps it up for this episode. Before we go, I want to encourage our listeners to follow us and rate us five stars on Apple Podcasts, wherever you download and stream the show. Even better, write a review and let other beekeepers looking for a new podcast know what you like. You can get there directly from our website by clicking on the reviews along the top of any web page.

We want to thank our regular episode sponsors, Betterbee, Global Patties, Strong Microbials, and Northern Bee Books for their generous support. Finally and most importantly, we want to thank you, the  Beekeeping Today Podcast listener, for joining us on this show. Feel free to leave us questions and comments at the Leave a Comment section under each episode on the website. We'd love to hear from you. Thanks a lot, everybody.

[music]

Brock HarpurProfile Photo

Brock Harpur

Assistant Professor

Brock Harpur is an Assistant Professor in the Entomology Department of Purdue. Brock arrived at Purdue after completing a National Science and Engineering Research Council Postdoctoral Fellow at the Donnelley Centre, the University of Toronto with Ben Blencowe.

His work explores the evolution and genetics of honey bees. Brock completed his Ph.D. on population genomics of honey bees at York University with Amro Zayed as an Elia Research Scholar. He's been a beekeeper for 18 years.