Nesting With A Naturalist
IRA FLATOW, host:
You're listening to SCIENCE FRIDAY, from NPR. I'm Ira Flatow. Up next this Memorial Day weekend, you know that it is the unofficial start of the summer, time to get outside, slow down, take a seat in the park or the woods, see what Mother Nature has been up to.
And my next guest has spent a lot of time doing just that. He's watched and recorded the activities of all sorts of animals, including bees and ravens and beavers. And while he's an insect physiologist by training, his lifelong love is birds, their nests and their eggs - and beginning with the first eggs that he collected as a child.
And he's gathered his most-recent observations on eggs into a new book. Bernd Heinrich is a biologist, writer, artist and ultra marathon runner. His many books include "Mind of the Raven," "Summer World" and "Why We Run." His latest is "The Nesting Season: Cuckoos, Cuckolds and the Invention of Monogamy." Dr. Heinrich is a professor emeritus of biology at the University of Vermont, and he joins us from the studios of Vermont Public Radio. Welcome to SCIENCE FRIDAY.
Dr. BERND HEINRICH (Author, "The Nesting Season: Cuckoos, Cuckolds and the Invention of Monogamy"): Thank you very much.
FLATOW: Tell us about these eggs as a kid. You got started collecting eggs as a kid?
Dr. HEINRICH: Well, I did collect some eggs then, yeah. I was fascinated by finding the nests, mostly, and, you know, because there was kind of a challenge to find these different nests, and I was also raising baby birds, and so I had to find the nests.
And we were living, you know, right after the war in Germany, and there wasn't much food. So sometimes, we'd you know, we'd look for crow nests just to get something to eat. So...
(Soundbite of laughter)
FLATOW: Did those eggs taste any different than chickens?
Dr. HEINRICH: Oh, I don't remember.
FLATOW: Don't remember. That's good.
(Soundbite of laughter)
FLATOW: If you want to talk to Bernd Heinrich, our number is 1-800-989-8255. You can also tweet us, @scifri, @-S-C-I-F-R-I. But you basically, your academic training, though, is in insects, right, in insect physiology?
Dr. HEINRICH: Yes, but I'm a biologist, and, you know, concepts transcend species and groups, and so it's always interesting to see how different groups solve the same problem. So it's all a matter of solving problems.
So with the birds here, I was really interested, you know, what is involved in parenting. It's a problem that we face, that all animals face, and birds are particularly interesting in the various mechanisms involved here because they have very different demands, and so you see what happens, what different environmental pressures produce different types of parenting.
FLATOW: And give us an idea of the various kinds of parenting that you found.
Dr. HEINRICH: Well, it starts with courting. So how are you going to evaluate the mate that you're going to have. It's a huge problem to find the correct mate, and then there is mating, and there is a nest, where to you know, it's kind of the home for the young, and it has to be safe.
It has to be warm, in many cases, and then you have the eggs and their predation there, and they have to be safe from predators, as well. And the care of the young is a huge problem to get enough food.
And, you know, but some birds, you know, they feed themselves. As you know, chickens, turkeys, ducks, et cetera, they feed themselves as soon as they hatch, and others have to be taken care of. So why all these different strategies? And so there's never-ending variety, but of course, there are some commonalities, too, that would be interesting to deduce from all of that.
FLATOW: You look at the concept of monogamy in birds, and some of you might have seen the movie "March of the Penguins" out there. And when we see these penguin couples devoted to each other, sitting on an egg for months, waiting for the mate to come back. How common is that in other bird species, besides just the penguins? Is that something that's unique to the penguins?
Dr. HEINRICH: Well, birds have the particular problem of the young have to have a time constraint that they have to grow up, usually in a season, to become independent. And so there's a huge problem with food. And as you saw with the penguins, there's also the physical environment, which really complicates the problem of food.
So it requires a supreme effort, and one parent can't possibly do it. And there you see an extreme example of that because one has to be with the eggs every moment, and the other has to provide the food. And so it takes a pair. And there is no time for dilly-dallying around.
FLATOW: Yeah, it's all work, work, work, taking care of those eggs. Let's see if we can get some calls in, our number 1-800-989-8255. Keith in Corvallis. Hi, Keith.
KEITH (Caller): Hello.
FLATOW: Hi there.
KEITH: Yes, professor, the question I have for you is you talked about generalizing between groups, and it may be a personal question, but does your knowledge of pair bonding in birds inform your personal life in any way?
Dr. HEINRICH: No, I hope not.
(Soundbite of laughter)
Dr. HEINRICH: If it did, then one person could, let's say with regard to our values, could pick the penguin and say it's exemplary, and somebody else would pick a bird of paradise and say they are just as good as penguins, but they have a totally different strategy.
So it doesn't relate to, doesn't relate to you or me, because they are different species, and they have different constraints. When we talk about, you know, what's necessary - and usually what's necessary is what has evolved, and the conditions are always different between different species.
KEITH: Yes, yes.
FLATOW: All right, Keith, thanks for your call.
KEITH: Thank you.
FLATOW: 1-800-989-8255. You wrote an op-ed piece for the New York Times about the movie that we mentioned, "The March of the Penguins," and in it, you wrote about the use of the word love to describe the relationship that these penguins have. Do they really you seem to make the case that the birds do experience love. Well, I thought that was a human trait.
Dr. HEINRICH: Well, certainly it's a human trait, but, you know, they have muscles, and we have muscles, too.
FLATOW: Good point.
Dr. HEINRICH: So are muscles a human trait?
FLATOW: Well, how do you measure love? I mean, what is the yardstick for measuring I know how we measure it in humans. How do we measure it in penguins?
Dr. HEINRICH: Well, I would say love has a functional significance, and that is attraction and bonding. And that's it maintains a bond. And it might be to a nest, it might be to an egg, it might be to a mate, but it's a psychological bonding.
I mean, it doesn't this bonding, where the male, let's say, mates are bonded, doesn't necessarily have to be by a psychological process. It can be physical. I mean, there are some fish, deep-sea fish, who live in the very deep oceans where it's dark, where males attach to the female, and they become like a parasite, and they're physically attached. So they maintain a pair bond, but it's not love, it's just physical. But I would say, if it's psychologically, then that's how I define love.
FLATOW: A big part of your book and I noticed that the illustrations are just magnificent in the book. Did you do you did those yourself. I mean, usually I mean, when I write books, I hire somebody because I can't even draw a stick figure to play hangman. But you seem to do such a great job in that. Have you always been that talented? Have you always wanted to illustrate your own stuff?
Dr. HEINRICH: Well, you know. I never really thought of myself as an artist. I mean, I do, you know, try to represent what I see, and I do it by photography, as in this book, and also sometimes photographs aren't adequate, and so you draw.
And I have to kind of get into the mood of what I'm drawing. I can't just draw anything, but I have to kind of get into the spirit of it, I guess I'd call it, to really feel it, and then I have the patience to sit down and work at it, but...
FLATOW: That's interesting. A big part of your book is devoted to something I think about a lot when I see different birds, and that is egg coloration. I mean, what can you tell about a bird by the way the egg is colored, or mottled, or spotted or whatever?
Dr. HEINRICH: Oh, there's it's hard to know where to begin, but basically, egg color is ultimately related to camouflage. And the most common camouflage is if eggs are deposited on the ground, and there's little nest, and the eggs have to be left alone without the bird sitting on them for a while, because incubation has to start after all the eggs are laid, so they are left alone, such as shore birds, for example. If they start to incubate after the first egg is laid and sat on it, the birds themselves might be camouflaged. But let's say if it was white and they left it, it would immediately be visible to crows, ravens, all kinds of other birds who - they all love to eat eggs.
And so as it is, now most shore birds, the eggs are so camouflaged you hardly wouldn't see them - hardly - have a difficulty to see them. And so...
FLATOW: So why would a robin's egg be blue?
Dr. HEINRICH: Good question. I...
(Soundbite of laughter)
FLATOW: And it is no blue really, in nature, except in the sky, right?
Dr. HEINRICH: Yeah.
FLATOW: And you're sitting on a brown background color.
Dr. HEINRICH: Yeah. Well, that is a really problematical one.
(Soundbite of laughter)
That's a really problematic...
FLATOW: I've always wondered. I thought you were going to answer that in the book because I've always looked at...
Dr. HEINRICH: Yeah. Well, actually, I had a title of an article, "Why is The Robin's Eggs Blue?" And that was sort of the ultimate question. That one, I really don't have a very good explanation except...
FLATOW: Good. I feel better.
Dr. HEINRICH: Yeah.
FLATOW: And I guess eggs - yeah, you say they're for camouflage and...
Dr. HEINRICH: Yeah. But the camouflage is not just from predators. The camouflage is also for egg - for cuckolding. For example, females will lay their eggs in others - other eggs of the same species. So part of the reason why robin's eggs are blue could be because other eggs are not blue in the sense that if your eggs are different from others, then it's difficult for another to dump their eggs into your nest...
Dr. HEINRICH: ...because then you would notice them.
Dr. HEINRICH: So in the other words, if all the babies had the same clothes, you could just interchange them. But if your clothes were -babies were different, then it would be difficult to be parasitized. So that's one of the reasons why. It's just for the matter of variety. And so you see this huge variety, and that's one of the reasons.
FLATOW: It's interesting. In your book, you tell a story of a woman who's strongly bonded with geese. She fed them. She let them into her house. She showered with and slept with them. Do you think that humans and birds can have an emotional bond like this? Did she - was she in love with the bird? When you say bird...
Mr. HEINRICH: Well, probably she did. I think so. Yeah.
Dr. HEINRICH: Yeah. Yeah, I mean, it does - you know, it's a neurological hormonal...
FLATOW: I'm tempted to say the word abnormal, but I don't ever want to say that in nature, you know?
Dr. HEINRICH: Yeah. Well, you know, different people like all kind of different things. I mean, I could do that, too, probably. I mean, I always get the brooding instinct in the spring. So maybe not that extreme but...
FLATOW: Yeah. Let me just remind everybody that this is SCIENCE FRIDAY from NPR News. I'm Ira Flatow.
And we're talking with Bernd Heinrich. Tell me about - when you raised birds, did they imprint on you? Did they follow you around after they hatch like you were mom?
Mr. HEINRICH: Well, I've raised geese and they do that. And so they are basically programmed to imprint as soon as they hatch, which means they learn something very quickly. They follow something that moves. This Konrad Lorenz was the one who kind of first came up with that idea.
Dr. HEINRICH: And it's usually thought that at that - that after the imprint on this another creature, say, rather than their own species, that they would later on be sexually attracted to them as well. Although the Canada geese that I've had, they came back actually and had - they left for a couple of years and came back and were just as tame, but they - these were females, and they brought back ganders and nested.
So they were - the imprinting on me was basically in attraction to me because I was the food provider, the safety provider so it made sense. But they would still had the urge to recognize their own kind, the same with dogs too. I mean, you know, they don't mate with people. Although sometimes they try a little. But they do quite well even though you might raise up a puppy.
FLATOW: Let me get in a quick...
Dr. HEINRICH: And the (unintelligible) follow you around.
FLATOW: Quick question from Kyle(ph) in Sacramento. Hi, welcome to SCIENCE FRIDAY.
KYLE (Caller): Hi. Thanks. Yeah. My question was, we just had doves, I think, made the nest and their hatchlings are born, and they just left a few days ago. But I was wondering, will that nest ever be used again by other birds or once? (Unintelligible).
FLATOW: Yeah. Well, will someone else use it?
Dr. HEINRICH: Yeah. Well, you're talking - well, it all depends. I mean, robins, for example, here that nest on a very safe spot where it's protected from the elements such as, you know, on a window sill or under a roof. Very often, they will use the same nest. Phoebes nesting in the shed where it's totally dry, they often come back and nest. They basically reuse the nest, and the nest is essentially a good nest site. So they'll build a nest on top of that so it tends to get larger and larger. The same with ravens, they will use the same nest on a cliff because there aren't too many places to build a nest.
But most birds, probably 99 percent, you know, they don't - they build a new nest every time. It's just those that have a very specific site, whether it's in a bird box or in a tunnel in the ground sometimes or...
FLATOW: Will they steal the material from an old, unused nest? The twigs in that?
Dr. HEINRICH: Well, if it's valuable material potentially, maybe feathers or something like that. But most of the nests I know of, they find their own new stuff.
FLATOW: Well, I want to say this is a very spectacular book. It's got great illustrations in it, great photographs in it. I know - I can see it's been a labor of love for you looking at the care. And...
Dr. HEINRICH: Well, thank you.
FLATOW: It's lucky you found a publisher who would publish colorful things these days.
(Soundbite of laughter)
FLATOW: And wish you a very much - a happy holiday this weekend. And thank you for joining us.
Dr. HEINRICH: Thank you. It's a pleasure.
FLATOW: You're welcome. Bernd Heinrich is an author. His latest book is "The Nesting Season: Cuckoos, Cuckolds, and the Invention of Monogamy." He is professor emeritus of biology at the University of Vermont.
We're going to take a short break and come back, talk about gardening on the cheap. Maybe you've seen the ads for those upside-down planters and gardening and things like that. We're going to give you ideas on how to use - how to take all that junk out of your garage and then turn them into planters and all kinds of interesting things. Maybe you'll have some hints you want to give us. 1-800-989-8255. We'll talk about gardening for frugal people. Stay with us. We'll be right back.
I'm Ira Flatow. This is SCIENCE FRIDAY from NPR News.