1 00:00:00,000 --> 00:00:05,000 Hello, my name's Lindsay Turnbull and I'm an associate professor in the Department of Plant Sciences 2 00:00:05,000 --> 00:00:10,000 at the University of Oxford, and we're right in the middle of this very serious corona virus crisis right 3 00:00:10,000 --> 00:00:15,000 now. And my students are all stuck at home and we want to keep them in touch with biology 4 00:00:15,000 --> 00:00:21,000 and keep in touch with us. And so we're going to make a new series of videos and they're going to be called back garden 5 00:00:21,000 --> 00:00:47,000 biology. 6 00:00:47,000 --> 00:00:52,000 Welcome to this next episode of Back Biology. It's the Easter weekend and it's almost eerily 7 00:00:52,000 --> 00:00:57,000 quiet around here. Even the buildings to those down have stopped. This episode is going to be about 8 00:00:57,000 --> 00:01:02,000 bumblebees. They're one of the real favourite insects that people enjoy watching. 9 00:01:02,000 --> 00:01:07,000 And we know that they're always doing something good. They're visiting our flowers, pollinating them. So we have a 10 00:01:07,000 --> 00:01:12,000 very positive image of them. And lots of people want to do more for bumblebees and try to plant 11 00:01:12,000 --> 00:01:18,000 the flowers that they like to come and visit and provide the kind of homes that they like to come and live in 12 00:01:18,000 --> 00:01:23,000 at the moment in my garden. Most of the buzzing that I can hear around me isn't coming from bumblebees. 13 00:01:23,000 --> 00:01:29,000 The most noisy insects at the moment are the hairy fosset flower bees. They're not a true bumblebee. 14 00:01:29,000 --> 00:01:34,000 What's called a solitary bee. And you can find both males and females of those buzzing 15 00:01:34,000 --> 00:01:39,000 around at the moment. They have a slightly HIGH-PITCHED Buzz. And every now and then we get 16 00:01:39,000 --> 00:01:44,000 the kind of bass note of a bumble bee going past. And we are seeing them, but they're very, 17 00:01:44,000 --> 00:01:50,000 very difficult to film because what those bumblebees are queen bumblebees coming 18 00:01:50,000 --> 00:01:55,000 out of hibernation and they're big and glossy and they're going around 19 00:01:55,000 --> 00:02:00,000 and they're looking mostly for nest sites and they're very difficult to film because although they 20 00:02:00,000 --> 00:02:05,000 look large and ungainly and not white, they ought to fly very well. In fact, they can fly very 21 00:02:05,000 --> 00:02:10,000 well indeed. And they go whizzing around co-authoring the ground in an area like this. 22 00:02:10,000 --> 00:02:15,000 And they're looking to see where can they build a nest and particularly what they're looking for, his 23 00:02:15,000 --> 00:02:21,000 old mouse nests, which make very good places for those bumblebee queens 24 00:02:21,000 --> 00:02:26,000 to found their colonies. So let's do a little guide to some of the common queen 25 00:02:26,000 --> 00:02:31,000 bumblebees that I'm seeing in my garden right now. And you're probably seeing the same species 26 00:02:31,000 --> 00:02:36,000 there, maybe one or two additional ones, depending on exactly where you live. But before we start that, 27 00:02:36,000 --> 00:02:42,000 I'm going to challenge you, get a piece of paper, get a pencil and see if you can sketch 28 00:02:42,000 --> 00:02:47,000 a bee and see if you can get the main parts right. And then pulls this video for a second. 29 00:02:47,000 --> 00:02:52,000 While you do that, men, you can press play again and see whether you got it right. 30 00:02:52,000 --> 00:02:58,000 Okay. So here are the main parts of a bee that you should have included on your diagram. 31 00:02:58,000 --> 00:03:03,000 The key thing when you're drawing any insects is to realise that it has three main 32 00:03:03,000 --> 00:03:09,000 body parts. So I'm drawing the head in no child's 33 00:03:09,000 --> 00:03:14,000 eyes, tongue and some antennae. Remember, high maths 34 00:03:14,000 --> 00:03:20,000 is the four X and then the bits at the end is the abdomen. 35 00:03:20,000 --> 00:03:25,000 OK. So all insects have this basic structure. This basic three part structure had four 36 00:03:25,000 --> 00:03:30,000 X abdomen ancestrally the ancestral insect probably had a lot 37 00:03:30,000 --> 00:03:35,000 more segments and they would have been a lot more similar. So before Axe is actually made up of 38 00:03:35,000 --> 00:03:40,000 three segments that have been sort of been cemented together over evolutionary 39 00:03:40,000 --> 00:03:45,000 time. So they look like a single segment now. And if you drawn legs and wings and I 40 00:03:45,000 --> 00:03:51,000 hope you have that we should all be coming off the thorax. None should be coming off the abdomen. 41 00:03:51,000 --> 00:03:58,000 Now, a bee is obviously an insect, but it's also belongs to a bigger group called the Arthropods. 42 00:03:58,000 --> 00:04:03,000 All the reports are characterised by these jointed legs, and all insects have six 43 00:04:03,000 --> 00:04:08,000 legs, three pairs of legs, all coming off the four x one from 44 00:04:08,000 --> 00:04:13,000 each of those ancestral segments. I'm going to just draw the legs in on one side, because the other thing 45 00:04:13,000 --> 00:04:20,000 that's characteristic of most insects, although some have lost them, are wings. 46 00:04:20,000 --> 00:04:25,000 So if they have two pairs of wings and they've been modified a lot in different 47 00:04:25,000 --> 00:04:30,000 insect groups. But in the bees, they always have two proper wings. The first 48 00:04:30,000 --> 00:04:35,000 part, normally the largest. The second, Paris smaller. And they are actually kind of zipped 49 00:04:35,000 --> 00:04:40,000 together as a little series of hooks between the front and the hind wing that keeps 50 00:04:40,000 --> 00:04:45,000 it almost functioning as a single wing. When bees land, they often fold these 51 00:04:45,000 --> 00:04:51,000 right back, actually over the body. So that's often where you see them and they snap them out with them up 52 00:04:51,000 --> 00:04:56,000 before they fly off. So that's a basic bee structure. 53 00:04:56,000 --> 00:05:01,000 OK. So what about some different common species of bumblebee? Well, they're not 54 00:05:01,000 --> 00:05:07,000 that easy to recognise. So I'm going to show you three that I think are quite easy to recognise, 55 00:05:07,000 --> 00:05:12,000 at least when the queens are around. This is at this time of year, of course, I've got my trusty play 56 00:05:12,000 --> 00:05:17,000 dough. And so the common khadir bee is a ginger 57 00:05:17,000 --> 00:05:22,000 bee and all ginger bee. So that means it has 58 00:05:22,000 --> 00:05:27,000 a gingery coloured thorax and a ginger coloured abdomen. And sometimes 59 00:05:27,000 --> 00:05:32,000 the abdomen is darker. It's streaked with black or blackish, but it always has 60 00:05:32,000 --> 00:05:38,000 a uniformly covered coloured abdomen. It never has a separate colour on the tip of the tail. 61 00:05:38,000 --> 00:05:44,000 And that distinguishes it from the tree bumblebee because they also have a gingery 62 00:05:44,000 --> 00:05:49,000 for thorax and. The abdomen is really black, though not 63 00:05:49,000 --> 00:05:54,000 really any hints of ginger at all. And at the end, a very clear white tip. 64 00:05:54,000 --> 00:05:59,000 This is a newcomer to the U.K. It's flown in from continental Europe in the last 65 00:05:59,000 --> 00:06:04,000 10 to 20 years, and it's established itself very successfully. And it does not seem to have 66 00:06:04,000 --> 00:06:09,000 any negative impacts on any of our other bees. So it's to be welcomed. And you sometimes 67 00:06:09,000 --> 00:06:15,000 see nests in old nest boxes or high up. There was one in my next door neighbour's garden, 68 00:06:15,000 --> 00:06:20,000 which they'd made it inside a sort of pergola. And we used to see them coming and going. So 69 00:06:20,000 --> 00:06:25,000 that's the tree bumblebee. I mean, another one that's easy to recognise when it's the queens 70 00:06:25,000 --> 00:06:30,000 anyway is the all black red tailed bumblebee. So she's got 71 00:06:30,000 --> 00:06:35,000 a black four acts, a black abdomen with a very clear red tip. We've got a beautiful, huge 72 00:06:35,000 --> 00:06:41,000 one flying around our garden at the moment, but I cannot get her on film because she's remarkably 73 00:06:41,000 --> 00:06:46,000 agile. So there's three common, easy bumblebees. Now, you might be thinking, hang on 74 00:06:46,000 --> 00:06:51,000 it, but why bumblebees? To me, surely bumblebees aren't supposed to be black and yellow striped? Well, those 75 00:06:51,000 --> 00:06:57,000 three are all quite common and they don't have any black and yellow stripes. But of course, other bumblebees 76 00:06:57,000 --> 00:07:04,000 do. So here are a couple of common yellow and black striped bumblebees. 77 00:07:04,000 --> 00:07:09,000 And they've got very similar names, as you see. They're called the white tailed bumblebee. And the buff 78 00:07:09,000 --> 00:07:14,000 tailed bumblebee. And again, these are what the queens look like. So the white 79 00:07:14,000 --> 00:07:19,000 tailed bumblebee, the thorax has one yellow stripe at the top. So it's a 80 00:07:19,000 --> 00:07:24,000 black thorax with a yellow stripe at the top. The abdomen has one yellow stripe 81 00:07:24,000 --> 00:07:30,000 quite high up, and then they have a clear white tail. The buff tailed bumblebee 82 00:07:30,000 --> 00:07:35,000 is almost exactly the same. Also has a black thorax with a yellow stripe at the front 83 00:07:35,000 --> 00:07:41,000 and the abdomen also has one yellow stripe. But then the tail is above 84 00:07:41,000 --> 00:07:46,000 colour. And it's only now when they're queens that you can actually tell these two apart. 85 00:07:46,000 --> 00:07:51,000 Once they start producing workers, then they'll all have white tails and you'll have no hope of telling 86 00:07:51,000 --> 00:07:56,000 them apart. You may notice in your garden another stripy 87 00:07:56,000 --> 00:08:02,000 black and yellow bee who has an extra stripe. So at this time of year, another queen 88 00:08:02,000 --> 00:08:07,000 who has a yellow stripe here as well. That's the garden bumblebee. So there are actually at least 89 00:08:07,000 --> 00:08:12,000 three common black and yellow striped bumblebees in addition 90 00:08:12,000 --> 00:08:17,000 to these others that we see here. So you may think bumblebees just about Pourbaix. 91 00:08:17,000 --> 00:08:23,000 But, you know, that's nature for you. We always have a lot of diversity and different 92 00:08:23,000 --> 00:08:28,000 species. And that was a great time to look out for them. Try and grab a picture as they fly 93 00:08:28,000 --> 00:08:33,000 past of the queens as they are searching for nest sites and feeding 94 00:08:33,000 --> 00:08:38,000 their first brood of workers who are usual footage 95 00:08:38,000 --> 00:08:43,000 of us trying to take pictures of queen bumblebees. Looks like this. You can see the bees flying 96 00:08:43,000 --> 00:08:49,000 around very actively. They don't settle. They're looking around the base of trees. They're looking 97 00:08:49,000 --> 00:08:54,000 under bricks and vegetation. They're looking for nest sites, not for nectar. 98 00:08:54,000 --> 00:09:00,000 But sometimes they do stop and fade. And here is that same queen falling 99 00:09:00,000 --> 00:09:05,000 out of a fertility flower as she is heavy and the inside of the petals are slippery. And there she 100 00:09:05,000 --> 00:09:10,000 goes again. Just needs a bit of practise. freeze-Frame we see two yellow stripes and a clean 101 00:09:10,000 --> 00:09:16,000 white tail. So this is the queen of the white tailed bumblebee. For contrast, 102 00:09:16,000 --> 00:09:21,000 here is a still picture of the buff tailed bumblebee. You see the tail not clean white, 103 00:09:21,000 --> 00:09:27,000 but a sort of dirty yellowish colour. And finally, here's the other black and yellow with three 104 00:09:27,000 --> 00:09:33,000 yellow stripes and a white tail. That's the garden bumblebee taken by my uncle. 105 00:09:33,000 --> 00:09:38,000 And finally, we managed to get some decent footage of this queen common Khadar 106 00:09:38,000 --> 00:09:44,000 bee. She's got a lovely gingery thorax and quite a gingery abdomen, 107 00:09:44,000 --> 00:09:49,000 certainly with no white tail. So that's the common car to be queen. 108 00:09:49,000 --> 00:09:55,000 So let's think about the lifecycle of the bumblebees. And they all have a pretty similar lifecycle. 109 00:09:55,000 --> 00:10:00,000 They come out now from hibernation in the spring and they're looking to found their colonies. They're not looking 110 00:10:00,000 --> 00:10:05,000 for mates. They already did that. They found a male at the end of last summer before they 111 00:10:05,000 --> 00:10:10,000 went into hibernation. And they can store that sperm all the way through the winter 112 00:10:10,000 --> 00:10:16,000 and use it now in their new colonies. Now, what they're doing, as I said, the first generation 113 00:10:16,000 --> 00:10:21,000 are going to retire is the first generation of workers, and they'll have to brood that generation themselves 114 00:10:21,000 --> 00:10:26,000 and feed them. But as soon as those workers emerge and can go off and forage for themselves, 115 00:10:26,000 --> 00:10:31,000 the queens will no longer leave the colony. They'll stay there laying eggs 116 00:10:31,000 --> 00:10:36,000 and producing more workers and sort of ordering the others around. And the workers will be going off and foraging. 117 00:10:36,000 --> 00:10:42,000 And that's when you start to see a lot more bumblebees. You'll see the populations really building up through the summer. 118 00:10:42,000 --> 00:10:48,000 Now, bumblebees have a Albie's belong to. A group called the Hymenoptera, 119 00:10:48,000 --> 00:10:54,000 and that's the bees. Ants and wasps, and they have some really strange mechanisms 120 00:10:54,000 --> 00:10:59,000 for determining sex. So at the end of the summer, once the colonies become very large, 121 00:10:59,000 --> 00:11:05,000 the colonies will switch, the females will switch to producing the males and 122 00:11:05,000 --> 00:11:10,000 the new queen. So everything will change or stop producing workers and now produce the new 123 00:11:10,000 --> 00:11:15,000 queens and the male. So how do they do that? So one way they do that is through 124 00:11:15,000 --> 00:11:20,000 the sex determination mechanism. So remember, we said with the fertilises that for most sexual 125 00:11:20,000 --> 00:11:26,000 organisms you have two copies of the instruction manual inside your genome. 126 00:11:26,000 --> 00:11:31,000 And we call that being deployed. So we are deployed organisms. And when 127 00:11:31,000 --> 00:11:36,000 we want to make new offspring, we have to, first of all, separate the two copies into 128 00:11:36,000 --> 00:11:41,000 one. So for an egg cell or a sperm cell only gets one copy of the manual. And then 129 00:11:41,000 --> 00:11:46,000 when egg and sperm cell fuse, we restore the deployed number. Now, 130 00:11:46,000 --> 00:11:52,000 in space and was something really strange happened. So if the female simply lays 131 00:11:52,000 --> 00:11:57,000 an egg, which is unfertilised and he has a single copy of the manual that 132 00:11:57,000 --> 00:12:03,000 will develop into a male. But if the egg is fertilised and it's a diploid 133 00:12:03,000 --> 00:12:09,000 embryo, then it will become a female. And that's unique to that group is a really strange 134 00:12:09,000 --> 00:12:14,000 system. And we call them haploid deployed because the males are haploid and the females 135 00:12:14,000 --> 00:12:19,000 are deployed. Now, the workers are all female and so are the new queen. So 136 00:12:19,000 --> 00:12:25,000 how does that work out? How do you decide whether you are going to become a worker or a queen? 137 00:12:25,000 --> 00:12:30,000 And that is under the control of the queen. So she releases chemicals inside 138 00:12:30,000 --> 00:12:35,000 the nest that suppress the ovaries of the work of females, which means that they 139 00:12:35,000 --> 00:12:40,000 can't have offspring of their own. And if that starts to break down, and it often does 140 00:12:40,000 --> 00:12:45,000 at the end of the summer and all hell can break loose in the colony and the workers can start to rear 141 00:12:45,000 --> 00:12:50,000 their own offspring. And that does happen. So the bumblebees seem like this very 142 00:12:50,000 --> 00:12:56,000 calm and ordered system. But actually, there's quite a lot of tension and conflict within the colony. 143 00:12:56,000 --> 00:13:01,000 And that starts to emerge as the season goes on. Well, we've spent the last week 144 00:13:01,000 --> 00:13:06,000 chasing after these queen bumblebees and we've really found it hard to get some of the Monville. 145 00:13:06,000 --> 00:13:11,000 We've really noticed that the car dibby that gingery bee. That's the one that's really quite friendly. 146 00:13:11,000 --> 00:13:16,000 We'll let you approach. The others are much more difficult. I'm not sure whether it's because they're still really actively 147 00:13:16,000 --> 00:13:21,000 looking for less. So they won't settle anywhere. Or whether they just are actually very skittish. 148 00:13:21,000 --> 00:13:26,000 So we're sort of frightened of bees. But it seems like they're pretty frightened of us. So if you're having if you're 149 00:13:26,000 --> 00:13:32,000 trying to get some photographs of queen bees, I hope you have a better job than I managed 150 00:13:32,000 --> 00:13:42,000 anyway. Until next time. That's the end of this episode. So happy hunting for queen bees. 151 00:13:42,000 --> 00:13:47,000 And we've found a bit of a casualty here. This is a queen of, I think, 152 00:13:47,000 --> 00:13:52,000 the buff tailed bumblebee and she is in the grass there 153 00:13:52,000 --> 00:13:59,000 and she's quite cross about something. And now I've made her rather irate. Oh, it's all right. 154 00:13:59,000 --> 00:14:09,520 So the fact that they failed to heed that.