Honey bee's social learning, pesticides problems and lessons for society - Dr. James Nieh
foreign Professor welcome to the show it is a pleasure and an honor to have you here I have requests from my audience to bring you here for a long time and I this is finally happening and I'm very happy for that. How are you today? Very good thank you and it's wonderful to be able to join you and I really look forward to our conversation. You recently published a paper very interesting paper in a very prestigious Journal science I would love you to give a little introduction about this article with us after you tell me a little bit how you get into the bees what's your background and how you get into the bees. I'm I'm really curious to know a little
bit more about that sure so uh it's a question people often ask me when I was an undergraduate I was trying different things and I took a course in animal behavior and communication that was taught by bird heldubler at the time who is famous for his work on social ants and I decided that I when I learned about the honeybee communication system and the waggle dance which ironically is what this paper is about I decided that I wanted to study it I wanted to learn more I thought it was unbelievable that an animal like a bee or actually any animal would have a language that was this complicated so I did a summer research project and I was trained in how to work with bees and train them to feeders by Professor Tom Seeley from Cornell University and I then became a graduate student in his lab so that's how I got started wow it's something that get attention of everybody about is I think he's one of the most magnets about how people get into business to understand their society how they communicate and so it's so impressive and interesting I think is one of the main magnets that attract people to to honeybees and and behavioral tell me a little bit about this publication because this is this is new to me apparently the bees teaching the other bees they need the older bees tell me a little bit more about that right so um the collaborators from China from the Chinese Academy of Science in Kunming Dr led by Dr Ken tan were interested along with me in this question why do we need to learn a language you know bees have a really complicated language is it possible that they just have it completely genetically encoded or do they need to learn in order to produce a waggle dance this is a question that many people have asked me over the years but I think the bigger question we were interested in is why is it that some animals need to learn language humans for example or even naked mole rats or canaries can learn parts of their Communication System but many other animals don't have to learn it at all imagine if you were born being able to speak Portuguese or English or Chinese it would be much more convenient but the the answer is as to why it's important to learn usually come down to two reasons number one you want to adapt to your environment so for example you might as a bird live an environment where you have different acoustic parameters and so you would want to optimize your communication so that your vocalizations could spread farther and be less distorted in that environment so that's a good example of why you would need to learn you can't exactly predict where you're going to be born the second reason is that communication can be very complicated if we think about how canaries communicate or many other animals it requires a lot of fine muscle control it requires the refinement of neural Pathways between the vocal tract and the brain and if you think about honeybees they have a really complex communication system of the wackle dance which we'll explain in a moment so it's quite possible that for either or both of these reasons honeybees might need to learn how to communicate from bees that are already older and more experienced wow and how how you do that how you demonstrate such things it's quite interesting the design that of that scientific article so we were following up on observations by other researchers that showed that when a honeybee and this requires monitoring a b throughout its lifetime which is possible now with video tracking and RFID they typically tend to follow older experienced bees as they get older before they themselves begin foraging now we should realize that how honeybees work their division of labor is based on how old they are they start out as nurse bees and as they get older they transition to become foragers so when they start becoming foragers one of the signs is they become very interested in waggle dances maybe that's just because they're interested in foraging but maybe it's because they're learning how to waggle dance so for the experiment we had to create two different kinds of colonies experimental and control in the experimental colonies we created what's called a single cohort Colony all the bees are the same age they were large colonies they had thousands of bees they had plenty of food so everything was fine and they also had a queen but they were all the same age in the experimental column in the control Colony same number of bees same amount of food also had a queen and the same genetic background meaning that we actually took a source colony and then split it into two which is very important but they had bees of all ages so they could learn from older bees whereas in the experimental Colony everybody was the same age so it's kind of like growing up without any teachers everybody has to go along at the same rate what you then have to do is you have to have a lot of help and you have to watch the bees in the colony not every bee in the colony but we individually painted on their thorax on the back different colors 200bs so we were able to track these 200 B's and when a bee is Young And A Nurse B it tends to hang around inside the comb but as it gets older it displays more interest in moving towards the nest entrance eventually starting to fly out and beginning to forage so in the experimental colonies we watch these bees every day throughout the day and when the first bees started to be interested in moving to the Colony entrance to begin the part of their life that they have as foragers we were able to immediately train them to a feeder now this occurred at nine to ten days of age in both the experimental and the control colonies which was great the difference was that in the control colonies at around this age they were also interested in following waggle dancers which they did but in the experimental Colony they could never follow any waggle dancers because everybody was the same age we then train these bees to a feeder and we looked at their first dances inside the nest when they came back so we could measure a lot of things about these dances we can and we'll explain that in the video but the dance communicates distance Direction and food quality how that works I'll discuss in a minute but there can be errors in all of these they might communicate the wrong distance they might communicate the wrong direction and we could compare the first dances of bees in the experimental Colony versus the control colony and as the the paper discusses in fact the first dances of the experimental Colony bees bees that grew up without any teachers without any ability to watch older dancers they were significantly worse at communicating Direction distance and also this thing called Dance disorder they were not producing a normal orderly dance now the second part of the experiment is we came back 20 days later and we looked at the same bees remember all the bees are marked so we know the bees that we're looking for in those 20 days in between we didn't provide the feeder so they just had it on the first day they were foraging and then 20 days later 20 days later however they were fully mature foragers they were actually near the end of their adult lifespan as foragers and we wanted to see did they improve in the control bees nothing changed they were still as good in their dancing 20 days later when they were fully adults forgers as the first time they tried to dance in the experimental colonies they also improved they improved their communication of Direction and they had dances that were more orderly that had less dance disorder however they were unable to communicate the correct distance in fact in the experimental colonies whether they were their first dances or 20 days later when they were much more experienced they still communicated distances that were too great which is really interesting um we know that in many languages there is a critical period where if you don't learn to do it the correct way that persists for the rest of your lifetime and it might be that this distance communication error is something that is persisting for The Bee's lifetime very very interesting and the way you summarize thing I think this is is the art because I was trying to summarize try to make it easier for for people to understand and I was having a lot of trouble Professor can we show that video and you can guide us about what we were seeing sure that's great please let's start the video and I will go ahead and narrate what we're seeing all right so here we see the image of the waggle dancer in the middle and the dance followers that are following it and here's a video actually showing the b in the center it's got the white orange dot on its back and it's being followed by other bees so this is the classic waggle dance now notice that the angle the B is moving when it's waggling it's about I would say 20 degrees to the left of the vertical position here's an example of another waggle dance and they're all pointing in the same direction because they're all being trained and indicating the same food location now these are pretty good waggle dances notice that each time she's more or less pointed in the correct direction the duration of the waggle run communicates food distance the farther away the food the longer the waggle run the direction as I just said points to the direction of the food relative to the Sun now you see other dancers and notice they're all pointed in about the same direction some of them are not exactly in the same direction this green one is making some errors but overall on average they're pointing in the correct direction now in this experiment we found that novices are able to learn how to dance better from observing other waggle dancers and you can see there are a lot of painted bees here these are all the bees that we were training and following in our experiment and this is a fun thing because there's a lot going on so it's good that people can train themselves on looking for the other dancers so I wanted to mention the amount of time that they should waggle to communicate distance as I said if they do it incorrectly or Learn Somehow incorrectly when they're young it appears to persist for their entire lifespan and this could be a form of cultural Transmission in other words maybe one generation will teach the next the incorrect distance encoding and I'll go over that in a moment but another reason that maybe bees need to learn is look at the dance floor so some bees are dancing on this brood cone that's covered with this fluffy wax some bees are dancing on the open comb we know that the dance surface influences the accuracy of the dance so is it possible by practicing by dancing on these different surfaces that they are actually learning to dance better over time that's something that's an experiment that we hope to to work and explore in Greater detail so people can now see the waggle dance and I just wanted to see if you had any questions for your viewers about things that they might want to know about this dance I was discussing with the people my patrons I have the patrons that who have discussions and some of my pages asked me and I was quite interested in that question too um because of the nature of the experiment that we force all the bees to have the same age and so they basically were kind of forced to mature faster if that would implicate in anything of the results that we're seeing do what what your thoughts on that so that's really interesting um however I should say that in both the experimental colonies and the control colonies the bees that began their first dances were the same age they in both cases they started dancing when they were 9 to 10 days old so it so yes in general there were probably some bees that were maturing more rapidly than they would have normally and that could mean that their brains weren't as correctly developed but since the control colonies also had bees at the same age we would expect the same level of cognitive development yeah interesting we are this is this is the main question that came from from my viewers uh the behavior of honeybees are not my background it's just something that fascinates me bring me to the question is what do we know about the communications of honey bees do I what do we know about them how how they communicate pheromones touching noise tell can you give us an overview about the current knowledge on how to be communication so honeybee communication is multimodal meaning that honeybees use multiple sensory abilities in their Communication System we can think about the sense of smell or olfaction which is largely through the B antennae so that is important because there are B pheromones like the queen pheromone now I'm going to focus on senses that are related to the waggle dance and B communication for foraging we know that when honeybees are waggle dancing they can heat up and as a result some odors are released from their body from the waxes that surround um their um their cuticle and these odors can be attractive to other bees similar to a pheromone but this is actually just the increased release of the odors and by attracting other bees to follow the waggle dancer these dance followers can more effectively get the information about where to go I just mentioned that bees are warmer when they are recruiting for a good food source part of that might be to release these attractive odors but bees can also sense temperature differences and so if a bee is a couple of degrees Celsius warmer she can be more conspicuous inside the colony and we think that that thermal difference is also attractive to followers bees when they're dancing if you think about it are moving very rapidly they're moving more than one body length a second and so they're also generating vibrations and sound the vibrations are fairly weak when they're running on the comb but they are something that we think that bees within one or two cells of the dancer can probably sense and again they may help her to find that dancer when the bees in the waggle phase I know that we had turned off the sound but you will actually hear a sound when she's waggle dancing and you can look at this in other videos or maybe you can show a clip later on but it's kind of a buzzing sound and that coincides with the waggle phase so the duration of that sound is correlated with the distance to the food source and we think that also provides information but speaking of information and B senses how exactly are the followers getting this information keep in mind that it's normally completely dark inside the colony so they can't see each other so what they are sensing is they can still sense the temperature they can still smell the body of the dancer and by the way the dancer brings back the odor of the flowers that she's been visiting either if she has pollen which is stuck on her legs or in the hairs of her body so she's conveying that information she's generating these vibrations she's generating these Airborne sounds that bees very close to the dancer might be able to hear but the most important thing appears to be touch if you are looking at those videos you might notice that the Rival dancer is waggling and the other bees are very close by and in fact in some cases their antenna is being hit by the body of the dancer so this Direct stimulation of the antenna this tactile sense is probably very important to sense where the dancer is and the angle of the dancer inside the nest so that's a review of the basic senses that are involved in honeybee communication I said earlier that I would tell you how bees communicate food quality there are two ways the number of times they repeat this waggle dance so one waggle circuit is a waggle run and the B returns around and then she Waggles again that would be the beginning of a second circuit if a bee really likes a resource like good food she can do this hundreds of times and the more she does it the more bees are informed about the location of the good resource so that's a major way in which they communicate food quality another thing that people have talked about for a long time in Carl Von Frisch who discovered the meaning of the waggle dance noted this as well is that b seem to be more excited when the food is better we now know that they're just faster so when the bee is waggling she's largely moving at the same rate but when she goes back around to waggle again she can do it slowly or she can do it really fast and if she does it very rapidly that return phase duration it means that she's more excited that the food or the resource is better so that's basically um the waggle dance in a nutshell communicating distance Direction and food quality uh the Weigel dance of course can also communicate the location of a nest site the location of water sources bees also need water and propolis or resin that bees collect for their health benefits but also to help build the column when you stimulate my mind professors so much uh because I want to ask you what happen if we disrupt this communication in small doses and I'm in the center there is a concern of mine a personal concern of mine because most of the pesticides are targeting neurons or the brain and and and when I look at the registration and how people see safety I it's my personal opinion I feel some gaps is in understanding the damage that pesticides of that nature could cause and I was wondering if I could ask you your thoughts on that matter do you think pesticides might be damaging their learning abilities or other things that may perhaps the regulatory systems are not being able to catch that's a great point so the the regulation is based largely upon studies of mortality do bees die or not within 48 hours or so of being treated with a pesticide but there are long-term effects on Survival that we know but whether you live or die is very very coarse way of looking at it because bees need to communicate and they have a lot of sophisticated behaviors work that um I have done with colleagues in my lab and with students has shown that there are multiple effects on B behaviors their ability to walk their ability to dance and their ability to learn so many research researchers have now shown that when bees and these could be stingless bees uh or it could be honeybees or even other kinds of bees when they receive sub-lethal doses of pesticides meaning they're not dying right away their cognition is impaired they have a reduced ability to learn and they have reduced memory and this can happen at any life stage for example larvae that are fed food by nurse bees that's contaminated with pesticides when they become adults they can also have poorer learning so in many ways for example we talk about lead and the effects of lead on human children when they grow up it actually reduces their IQ reduces their ability to learn very similar to the problem with pesticides that fascinates me um it is a really a real concern of myself um and I don't know what to do about it to be honest other than try to educate people here in this Channel and to perhaps convince people at home to to at least to be informed about the consequences of this chemicals that I see everywhere I go when I walk in my dog I can't get rid of them in my life so it's a concern of mine maybe can I perhaps stick your brain about something else about honey bees Society is that it's also something that fascinates me what honeybee's societies could teach us about to be a better Society I would like to to know your thoughts on that that's really great point I think that humans have long admired bees because they live in a largely harmonious Society where they're working together and cooperating now there are exceptions to this of course but in fact there's a great deal of cooperation which we think originally was largely driven by the close genetic relatedness of the bees inside the colony in fact of course even today we have a society which is which has a queen and then the workers who are all her daughters are therefore closely related I think what we could learn is two things yes they work together but there are still actually police in the Bee Society so um I I think the lesson is it's not as harmonious as we would think but some of that disharmony does have a function so maybe I'll give you an example the most important thing in maintaining the society is that the queen produces all the eggs and so the workers are all her daughters now very rarely about one in ten thousand eggs the queen can lay about two thousand eggs a day but one in ten thousand eggs it turns out if you genetically analyze it is not laid by the queen it's laid by a worker so this is called Rebel Behavior because you're rebelling against the Queen by producing your own offspring not taking care of your brothers and sisters but this could cause a problem however what happens is that there are worker police so there are bees that are specialized in going around they can smell the eggs and from that they can know whether or not it was laid by queen or by one of her daughters and they will eat the egg that was laid by the daughter so you could say well one in ten thousand isn't very bad right but obviously it is an issue because the worker police have evolved there are cases where colonies are called anarchistic colonies meaning that there is anarchy because they have genetic mutations in which worker cheating is much more widespread and in these colonies and and I think maybe this is also something that Society could learn they don't survive that's because it needs the harmony of every Everybody cooperating together and working to take care of the Queen's Offspring for it to actually survive the only way that we are able to maintain these anarchistic colonies which are fascinating to study is by artificially feeding them because they are unable to really sustain themselves by providing for their own food so I think that's one of the things that we can learn from honeybees another thing that we could learn is we talk about the queen and um you know it's ironic we are about to have a a new monarch crowned right uh King Charles of England but the queen is not sitting there on a throne telling people or bees what to do in fact the queen and the workers are in a very symbiotic relationship when a queen gets old if she reduces the number of eggs that she can produce then she can be replaced which means simply that her daughters will kill her and they will take one of her eggs and raise a new Queen now the workers have a lot of say in raising those new Queens they take the eggs they will actually put them into Queen cells and if the workers decide that the colony has grown very large and needs to split by swarming and creating two colonies they're going to need two queens one Queen to leave with a swarm and one Queen to stay behind so the Queens are producing tooting and quacking sounds which we think May communicate to the workers that they are about to emerge the workers have communication signals as well that can apparently tell the queen that they should not yet emerge because when a queen emerges she will go around and kill all the other queens in a normal non-swarming situation when the workers decide that they need multiple Queens then they could actually suppress the Queens from emerging so it's not quite a monarchy that we think it is the workers can kill the queen if she's not a good Queen they can decide when the Queens emerge and they can prevent the Queens from killing each other the other thing that is important to realize is that we know that honeybees have a haplodiploid sex system what does it mean well basically virgin birth a female bee like the worker can lay Sons because she can produce eggs that egg is not fertilized it becomes a male if it's fertilized with a sperm then it becomes a female so it's a very interesting sex determination system what it means is that a queen mates at the beginning of her life and then she stores the sperm from multiple males inside her body in a spermathica for the rest of her life she never goes out again to mate she as the egg is passing through the oviduct of the queen she can decide to open a little muscle and let sperm from the spermaphica contact the egg fertilize it and it goes down and then it becomes a female so you would think great the queen can even control the sex of her offspring but there's a catch drones are bigger than workers you've ever looked inside a colony you'll see the bigger bees with the very large eyes so drones need to be born in drone comb which has a larger diameter than worker code who builds the Drone cub the workers so if the workers decide that they don't want any drones they can either not build drunk home or they can fill the Drone comb with honey and pollen so the queen can't lay any male eggs now you might say well how does the queen know if it's a drone comb or a worker comb when she's going inside the cell to lay an egg she's actually measuring how big it is with her legs and she can then know that this is something where she can lay a male egg or something where she can only lay a female egg so the lesson from that is that there really is a kind of reciprocal relationship between the queen and the workers it's not just that the queen is telling people what to do or telling the bees what to do I think that's that's tells a lot about what we need to learn about them there is no dictatorship or any sort of mandatory is it is a cooperation or everybody it's United for a specific goal of survivorship of that Society it so I think that tells a lot but first I want to thank you very much for your time this was a great discussion and congratulations with your uh publication and good luck to you and your team to to do much more of that thank you very much it's been great to chat with you and I look forward to to seeing the podcast
2023-05-31 21:14
