IndiaAsksWhy | Why do birds fly in groups?

IndiaAsksWhy Episode 3 | S1

Have you ever looked up at the sky and wondered why some birds fly in groups? Join Utsuka and Jigyasa to find the reasons why. 

In the Ask A Scientist segment, they both talk to Vishwesha Guttal (https://​tee​labi​isc​.word​press​.com/), a theoretical ecologist, to know why some animals group whereas others don’t. He also talks about how researchers use maths and computers to study grouping and other behaviours.

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You can send your questions to Utsuka and Jigyasa at indiaaskswhy@​gmail.​com, or join their Telegram group for updates and fun science discussions.

Join Utsuka and Jigyasa as India becomes more curious, one question at a time!

Podcast Duration: 14 min 18 sec

Stay tuned for more updates from IndiaAsksWhy!

Utsuka — U, Jigyasa — J

Transcripts with Timestamps

Both- Hi Everyone”

U- I am Utsuka

J- I am Jigyasa

Both- And you are listening to IndiaAsksWhy

U- A science podcast supported by IndiaBioScience

J: Where we do the research for you to get smarter.

U: Join us, as India becomes more curious,

Both: one question at a time!

[00:34] U: Have you ever looked up in the sky and wondered why some birds fly in groups? Well, Utsuka and Jigyasa have wondered about it too. Join them as they explore the reasons why some birds form groups. In the second segment, we have Dr. Vishwesha Guttal from the department of Ecological sciences at the Indian Institute of Science who among various other cool ecological phenomena also studies why animals form groups. Apart from asking questions about birds flying in groups, Utsuka and Jigyasa also get to hear from him about what it means to be a theoretical physicist and how he studies birds and other organisms in his lab!

[01:37] U: You all must have heard of the phrase, Birds of a feather, flock together’. Ever wondered why this is so? Like why do some birds fly in groups?

[01:51] J: Flying together is such a complex task and might require a high level of coordination. I am sure it has something to do with the bird’s survival.

[02:01] U: Survival? Do you mean being in groups helps these birds live longer?

[02:10] J: Oh yes Utsuka! Some birds fly together to get the maximum benefits of their numbers. They are a large team that flies together and survives together.

[02:21] U: Oh! Like the age-old quote, United we stand, divided we fall’.

[02:26] J: Exactly. Several studies on a small bird called the European starling’ have shown that when a bird on one side of a group stalks a predator, it makes slight movements in its position. This way it is able to signal as many as seven birds around it to do the same. So all the birds can move away from the threat. Sometimes this coordinated flapping of the birds’ wings can even startle the predator away from the group.

[02:57] U: Oh! That’s very smart of these birds. I am also curious about what are the other ways in which a large number of birds help them survive better.

[03:07] J: So recently researchers have found that birds like the pink-footed geese and our common passenger pigeon fly together to look for food. Some birds even go ahead and make nests close to each other.

[03:20] U: Oh! The way we like to build homes close to each other?

[03:27] J: Precisely. The way we like living close to each other so that we feel safe, birds do the same. Some birds even take a chance to sit on the same tree together. It’s like something the way we humans do in winters… we like to cuddle to stay warm. So sitting on the same tree actually helps the birds to stay warm in the same sense. They help maintain their body temperature.

[03:46] U: That’s very interesting. But I have one more question. What about the magnificent wave formation that we see in the sky? Why do some birds fly like that?

[03:58] J: Oh Utsuka! Have you seen airforce fighter jets during independence parades?

[04:01] U: Yes. I remember.

[04:04] J: They also make the same V formation’. Because it saves a lot of energy. So when the birds need to fly really long distances, they make the V formation’ so that they are able to save energy during such long flights. When the leader bird flaps its wings, it creates an updraft in the air. It makes it easy for the birds behind it to fly. It is especially advantageous when a bird gets old or sick and is unable to fly. This way they get to choose to stay at the back till the time they recover.

[04:35] U: Oh so you mean that the leader does all the work and the rest of the birds benefit? That’s not fair for the leader.

[04:42] J: No, no, no Utsuka. That’s not how it happens. The birds in the group take turns to lead it. So when one leader gets tired it switches position with another bird.

[04:54] U: Oh! That’s some bird team spirit right there. And we ought to learn team spirit from these birds.

[05:02] J: Definitely. So flying together is always advantageous. Living in a community helps.

[05:12] J: And now, it’s time to ask a scientist.

[05:17] U: Continuing our exploration from the previous segment, we now have Dr. Vishwesh Guttal who is going to answer some of the questions that we didn’t answer in the previous segment. Jigyasa, why don’t you go ahead and ask your question?

[05:30] J: So Dr Guttal, Why do you think only some birds fly in groups?

[05:33] G: So if one way we think about this question, the important way to think about this question across all organisms is that we used to think of what are the costs of showing a group behavior whatever the benefits are of being in groups. Now if the benefits outweigh the cost, the animals live in groups. The moment those become equal, they reach the equilibrium of group size, and group property they are in. But the moment cost begins to dominate, then they again stop grouping.

[06:15] U: So when I think of ecology, I think of fieldwork. So how do you actually study these organisms and why do they sort of form communities and so on? [06:30] G: Okay. So whatever I have just told you conceptually and verbally we can sort of explain them mathematically with some equations and some functional forms. And we make some predictions as to what could be an optimum group size or what could be an evolutionary equilibrium. If these kinds of costs and benefits are at play. That’s a computing part of our expectation. On the other hand, if you are an experimental person or you want to test your theory, you also go on and think of measurable quantities that could give us some handle on what are these benefits. What are these costs? How can we really go on and measure them in the field? Okay? And that’s a different challenge entirely altogether. So here we measure whatever the benefits and costs in an experimental setup and in theory we sort of formulate them, mathematically calculate and sometimes computationally calculate. So these are two approaches and they go together you know. They cannot be done entirely independently of one another to make sense of the natural world. And those kinds of formalisms tell us why in some cases animals form groups whereas in some other cases animals do not form groups.

[07:50] U: So is it just ecological context or it is more sort of kind of birds, how big or small that makes a difference?

[08:00] G: It can make a difference. It is also a part of ecology. What are their body constraints, and what are their physiological constraints? So they all play a role. In fact within a species, if you look at their life history, there are changes in the way animals group. So there are many fish species, when they are juvenile, you find them in large groups. I know they are tiny and highly predacious by larger organisms. On the other hand, as they become big the chances of predation reduce and mating is the main factor contributing to their future fitness now. So therefore even if it means a potential risk of predation, it is now better to focus on the mating part. So they often are not grouped. They might not even be in smaller groups. They are often in pairs, okay? When it comes to mating… even for a species, across their life stages, their grouping behavior changes. So it usually depends on the question. Do we want to understand a given species and how it is evolving across life history? Or do we want to understand a life history stage, why it is doing what it is doing? So yeah depending on the context we study using appropriate tools.

[09:34] J: It’s nice. Right so… did you have an interest in studying these animals from the very beginning?

[09:43] G: You know I mean like a lot of people, I also like nature. But my training was in physics. For me, for a large part of my life biology meant a lot of memorization and mostly cell biology. Therefore I always stayed away from it. So what really excited me were the things that I can actually observe and literally see with my own eyes. You don’t need a microscope to observe birds flying, you know on your terrace. Or even insects or worms on the wall of your garden or ant traces that we see everywhere. So you don’t need a microscope or an extraordinary instrument. So what it really was is that they can be really understood by what we call sophisticated mathematics and physics. For me, that was extremely appealing.

[10:38] U: Okay so talking about your lab life, what is something that excites you the most? What is something that keeps you going?

[10:45] G: Tough question. There is some essence of elegance in studying nature and thinking about answering these questions and that is one driver. It is not just doing research, nothing else. It is the combination of research and the opportunity that allows us to interact and think more about those questions, and talk to people and teaching also plays a really engaging role.

[11:15] J: That’s very cool. So we want to know what is that one message you want to give to our listeners about doing science or about a career in science probably.

[11:28] G: I think, thinking about how science functions are also important. Perhaps even more important than learning various aspects, specific facts. I think just knowing facts is really boring. But to know about how did people discover that ants produce ceramons’? We need to think more on those lines. I think that is also really really important. Now for those who are interested in a scientific career, if you are truly passionate about science and if you really want a career in science, Go for it. Don’t hesitate.

[12:07] J: Do you now understand why birds fly in groups?

U: Yes. So it depends on a lot of factors it turns out. Like bird size, risks, benefits, and uses. Some birds fly together to protect themselves from predators whereas others do so to make long-distance flights easier. Theoretical ecologists like Dr. Guttal himself write mathematical equations which represent these factors and use computers to find reasons behind why some species group.

J: And Dr. Guttal recommends going beyond the simple facts in science and thinking about how they were discovered.

J: But listeners, what we know about these birds might change as we get more evidence over time.

U: Who knows one of our listeners in the future might study these birds and find something about them that we never knew before.

J: So U: Stay Curious Both: and ask questions

U: So, that’s it for today. We would like to thank Dr. Vishwesha Guttal for letting us interview her.

J: If you want to know more about him, we have linked his profile in the Show Notes!

U: If you have any questions shoot them away to Indiaakswhy@​gmail.​com

J: If you’d like to directly talk to us and join the fun, join the fun on our Telegram Group. Link in the show notes.

U: For updates on IndiaAsksWhy, follow IndiaBioScience @IndiaBioscience on Twitter, Instagram, Linked In, and Facebook! (link in the show notes as well!)

J: Shweata N. Hegde and Ruchi Manglunia are the hosts of the podcast

U: Ira Zibbu helped us transcribe and design the interview segment.

U: And we are thankful to IndiaBioscience for hosting us.

J ‑So stay tuned and stay curious!