Scientific American assistant news editor, Tanya Lewis, and collections editor, Andrea Gawrylewski, host a new podcast that takes a deeper look at short articles from the Advances news section of the magazine.
Scientific American assistant news editor, Tanya Lewis, and collections editor, Andrea Gawrylewski, host a new podcast that takes a deeper look at short articles from the Advances news section of the magazine. This episode they talk about the articles "Tinder for Cheetahs? Big Cats Are Attracted by Urine Smell" and "Blind Except for Movement: Woman’s Injury Offers Insight into How the Brain Works."
Tanya Lewis: I’m Tanya Lewis, the assistant news editor at Scientific American.
Andrea Gawrylewski: And Andrea Gawrylewski, the collections editor.
Lewis: And on this episode of Science Talk we preview a new Scientific American podcast where we talk about some of the stories we’ve loved from this months’ issue in the section called “Advances.”
Gawrylewski: Tanya, can you tell all the listeners what the “Advances” section is and what it covers in the magazine?
Lewis: Sure so “Advances” is basically you know our front-of-the-book news section where we cover cutting-edge advances and discoveries in fields ranging from technology to health to neuroscience and many others.
Gawrylewski: Great so what is on top for today?
Lewis: For today’s episode we’ve got a story about how cheetahs choose mates based on the smell of their urine.
Lewis: And the story about a woman who has a rare visual condition where she can only see moving objects and colors.
Gawrylewski: Wild. Let’s dive in.
Lewis: Believe it or not that’s the sound made by a full-grown cheetah and our first topic is a story called “Tinder for cheetahs” by Joshua Rapp Learn. It’s about an innovative approach scientists are taking to help zoos breed cheetahs in captivity. Zoos often try to mate the big cats with cheetahs at other zoos that are less genetically related and they fly these animals all over the country but it turns out the female cheetahs are very picky about their mates so to up the odds on these cheetah liaisons being successful, researchers presented female cheetahs with urine samples from several males and let the females choose which one they like best.
Gawrylewski: Um, how [laughs] does one exactly go about collecting cheetah urine?
Regina Mossotti: [laughs] Very carefully.
Gawrylewski: I’m sure.
Mossotti: To collect the cheetah urine we developed ultimately what are cheetah urinals.
Lewis: That was Regina Mossotti, Director of Animal Care and Conservation at the Endangered Wolf Center in St. Louis.
Mossotti: We used a galvanized steel plate. We constructed it so that it funneled into a collection cup and cheetahs put different smells on the ground. They love to scent roll on them and rub on them. Cheetahs take a step further and like to urinate on them.
Mossotti: So we could cheat a little bit and put some fun scents on the tree, the same tree that the collection, the urinal was on and it made them want to mark that scent and so we would be able to capture the urine through their wanting to mark that fun scene that we gave them.
Gawrylewski: What is the fun scent you gave them?
Mossotti: You know we did a couple different things. The one that worked the best was Obsession for Men.
Mossotti: By Calvin Klein.
Mossotti: And that almost 100 percent of the time it got them to urinate [laughs] but after a while, once they got used to that scent, we would try other things, other different perfumes. We tried catnip. We would try other male’s urine, something that made them want to mark their territory or a scent that was interesting that they wanted to mark and claim
Gawrylewski: I feel that Calvin Klein needs to know about this?
Lewis: [laughs] Yeah.
Gawrylewski: There’s a whole new market, an untapped market for that.
Lewis: [laughs] Exactly.
Lewis: Why were you gathering urine to offer to these female cheetahs, like, why did you think that that would be important in helping them find mates?
Mossotti: So when we first identified the need for this research, the reason for that was cheetah reproduction in/across the United States, in many areas, wasn’t doing as great as the Species Survival Plan had hoped. The Species Survival Plan is a group of experts that come together to manage an entire population of endangered species and they’re very careful about who breeds with whom to make sure those genetics stay healthy and they manage the population across the United States so whether a cheetah is in a zoo in California or one in Florida, they know the exact genetics of those animals and they pair them based on that and one of the things that they watch for is when they put these pairs together is do they have cubs? Do they actually mate and produce a litter? And unfortunately the production of litters was not as high as the professionals had hoped and so one of the things that we had scene that at a few of these institutions, the reproduction was pretty consistent and they were doing well and we realized that one of the things that they were doing differently is they had what was nicknamed [laughs] the “Lover’s Lane” where they have multiple males and they walk this female down a corridor surrounded by these different male enclosures and she can walk by these males and investigate them and figure out which one she likes the best.
Lewis: That sounds great.
Gawrylewski: Yeah it’s like cheetah speed dating basically.
Mossotti: [laughs] Exactly. That’s exactly what it is.
Lewis: Except with urine. [laughs]
Mossotti: The hope with the cheetah urine study is first we needed to see if females were even interested in the urine because there’s a lot of different ways that animals make mate choices: How the animal looks, how the animal acts, its behavior, smell but smell in different ways and so this was kind of a very groundbreaking beginning part of really investigating cheetah mate choice and at first we just wanted to see if the cheetahs, the females, were interested in the urine. We assume they were based on previous studies of a lot of different mammals that urine kinda seemed to be the Facebook or Tinder of the animal world where you can get so much different information whether you’re related to an individual, whether that individual’s ready to mate, whether they’re healthy, all things that are important when you’re making a mate-choice decision but to add to that we also offered the female male urine scents of varying relatedness. So she even had three choices, one that was a good match that would be a good mate choice. One that was a medium choice, maybe a second cousin, you know? Not the best mate choice but not the worst. And then one that was really closely related, a father, brother, uncle, something that…,you know, an individual that she wouldn’t want to mate with, and so we offered these three scents to see what her reaction was.
Lewis: And what did you end up seeing with these choices?
Mossotti: Well that was the exciting part. So we saw that there was significant response to the urine scents of more distantly-related males, the ones that would be a better mate choice so that was very exciting that maybe we need to now take the next steps of seeing if that translates to mate choice but if it does that maybe, in the future, we can instead of shipping the males across the country, we can ship urine from several different males, let her smell it, see which one she spends more time with and then choose that male to send versus one that maybe she’s not as interested in.
Gawrylewski: What kind of when you say to see if she spends more time with that urine sample, what does that look like? What sort of behavior is she displaying and how are you presenting it to her that she would spend more time with one versus another?
Mossotti: So we put it in a PVC pipe, a small PVC pipe that has its holes drilled in it. We poured a small sample of urine on a piece of gauze and stuck it in this PVC pipe and sealed that and we actually tied ‘em to trees because we found that the cheetahs like to carry away the scent to an area that we could watch them and observe them. So we put it on a tree, chained it to a tree and then we watched, observed her to see what her reaction was. Did she sit by it longer? Did she smell it more? Did she lick it?
Did she paw at it to try and get at it? Was she showing behavioral interest in it compared to the other scent that was there? And so we offered two scents at a time and we did that so that all combinations of the pairs were done multiple times over the course of several weeks and it was neat to watch, you know, just to see. We had no idea what they were gonna show, what the response was gonna be but it was neat to see what their interest was and when we offered the scents we didn’t know which scent was in which pipe so that we could have our own bias towards it so that was a really neat part of the project was to really see what the females’ responses were. The cheetah has really…and that’s one of the reasons I love the cheetah so much s that it’s always stood out to me as this misunderstood animal that is just gorgeous and, like I said, as an apex pair is so important to the ecosystem that as much work and research as we can do to learn more about these animals to help us with our conservation effort, the better and that’s one of the reasons that we did the Captive Program, looking at mate choice here, is because the zoological institutions across the United States play an integral role in conservation of animals out in the wild.
The captive population is kind of like Noah’s Ark for the wild population meaning that if the wild population crashes any further, if we ever need to reintroduce cheetahs, we need to have a healthy, genetically viable population in human care at zoological institutions and making sure that we are managing the animals so that they stay healthy is really important to that potential need.
Lewis: Let’s switch gears now to our second story.
Gawrylewski: It’s based on an Advances article called “Seeing Blind,” by Bahar Gholipour. A woman in Scotland named Milena Canning is blind, except she has this incredible ability to see moving objects, still. She can also see bright colors and sometimes the outlines of objects if they’re right next to her. Milena suffered from a stroke about 20 years ago and was put into an induced coma when that happened and when she woke up, she had suffered tremendous brain damage and was completely blind. Over the coming years, however, she eventually started regaining these particular vision abilities
Lewis: I wonder what it’s like to have this condition.
Milena Canning: Everything’s in front of me but I feel as if I’m underwater, as if I’m in a swimming pool and you’re swimming under the water.
Gawrylewski: That was Melina Canning herself. We spoke to her about her unusual visual condition.
Canning: Everything is there, all. All the colors are there but it’s as if it’s all floating in the water and if I look to my right-hand side just now I see an outline of my coffee cup, sitting to the right-hand side of me. It’s bright-red in color because colors are good for me so I know where it’s sitting and if I just stare at it just now I see the roundness of the coffee cup at the top and then I just stare and stare at it and then I see the handle at the right-hand side and then I know then to go and pick it up because I just see the outline.
Gawrylewski: And this condition has a name. It’s called Riddoch syndrome, named after the neurologist George Riddoch who first described this phenomenon in brain-injured World War I soldiers.
Canning: I suffered a stroke 19 years ago now, and I had been placed in an induced coma for 52 days and they told me…. So I had the stroke while in the coma so then when I woke up I discovered I was left blind and that was in the February and then over the months you know by the June I felt as if I was seeing some color and then by the September it was just really improving. Erm you know when I say improving I mean it was colors I was seeing, really.
Lewis: And do you have to be moving in order to see this or does it just sort of you can see the outline even when you’re standing still?
Gawrylewski: Yes even when I’m standing still, seeing this outline, you know? I’m just sitting here and not moving, I’m just staring at the cup. The interesting thing is … I’ve said in the past in the past in interviews that if my husband or anyone makes me a cup of coffee and they bring it from the kitchen into my living room to set it down beside me, I can tell, straight away, if I just stare at the cup, I know, straight away, if the handle is facing to the left or to the right and because I’m right-handed I’ll say to my husband, “The handle’s not at the right-hand side for me to pick it up” so then I’ll move the cup in order that I can see the handle at the right-hand side. Now I never, ever saw that about a year ago. I mean it’s only … or maybe longer than it … I mean it’s only recently I’ve started seeing that. It’s very, very strange.
Lewis: So it’s sort of like a dynamic condition that you know has been changing over the years.
Canning: Oh yes, yes because … yes when I first woke up that was February. Now it would be February, ’99 when I had my stroke so when I first woke up, I was completely black, couldn’t see anything and it’s just been changing over the last 19 years. It would just start small things, you know, like seeing the colors. That was all maybe I used to see was a bright color and now it’s you know I see, like I said, I see this cup sitting here and the handle there and I can see the steam coming from coffee cup but if you’re sitting next to me and we’ll look at each other, I can’t see you. I don’t see your face.
Canning: But if we stare at each other and then I say to you, “Can you blink your eyes,” I see the movement of your eyes blinking and then I’ll look and I get maybe your chin and then say to people, “Right, speak to me.” And as you’ll speak, I see your mouth moving but that’s all I get. I don’t get the full picture of your face.
Lewis: One of your doctors gave you a rocking chair sort of along the process thinking that that might help you create your own movements and that you could see things as though you’re the one moving. Did that help you at all?
Canning: Yes it did in the beginning, it did, yes. That was a Professor Gordon Dutton that told me to do that and my mum actually had a rocking chair at the time so I used to sit in that and the rocking movement but yes that was when he first told me to bring things in to focus. He would say, you know, “Shake your head, move your head,” you know? If I dropped something on the floor and then I would look down to find it and I would just stare and stare at the floor but I couldn’t see it and he would say, “Well, shake your head and bring the item into focus” so I would and then I would just see it lying there on the floor.
Gawrylewski: We talked to Dr. Jody Culham about what’s going in Melina’s brain that enables her to see movements and colors even though she’s legally blind.
Jody Culham: I’m a professor at the Brain and Mind Institute and the Department of Psychology at Western University in London, Canada.
Lewis: Can you just tell us a little bit more about the injury that caused this condition?
Culham: When Melina was about 38 she developed a respiratory infection and she went into a coma for almost 2 months and when she came out of the coma she was completely blind and then gradually over the next month she began to experience some different types of vision. So while she was in that coma, she had a stroke or a series of stokes that damaged a region of her brain about the size of orange at the very back of the brain and that’s an area called occipital lobes where visual input that comes from the eyes gets richly processed and she’s missing most of that visual cortex at the back of the brain and yet she still has visual input through what we think are some side roads into some of the higher-level visual areas. So the way that I would think about it is that you’ve got one really important hub of the visual system missing but there is still some side-road connections that can bypass that hub and get to other areas that can use visual information. And so she’s learned to rely on those, those side roads, and take advantage of them in order to do things but she certainly doesn’t have anything near normal vision. But that doesn’t mean that she doesn’t have useful vision.
Gawrylewski: What do you say about what your team and you have learned about how the brain processes visual content using Milena as a test case and doing brain scans and collecting the data that you have?
Canning: So the most striking thing that we found from the brain scans was that although she was missing most of her visual cortex she did have an area spared. There’s an area that’s been quite well-studied by neuroscientists that goes by the name MT, the middle temporal area of the brain, and it’s just kind of right on the sides of your head, just a little bit behind your ears, behind the tops of your ears on both sides of the brain. And that area we know in typical participants will respond whenever people see something that’s moving and she shows spared activation in that region when she sees something that’s moving even though all of the brain tissue that’s behind that is completely gone so we think that her case has really provided strong support for a critical role of this region in the ability to perceive motion. And it also provides a nice counter example to another single case in the literature. There’s another patient who I think has passed away now but while she was alive she had this syndrome that was almost the reverse of what Milena has.
So this other patient had damage to this area, MT, this area that’s involved in motion, and she could see everything except motion so for this patient she didn’t have any problems recognizing things but she couldn’t make decisions based on motion. So say for example she was pouring tea into a teacup, she couldn’t see the height of the tea rising. She would have to sue other strategies like putting her finger in the teacup and feeling when it reached the right height or she had to do things like a crossing a road when there was traffic, she had a really hard time knowing when to go because she couldn’t gage the speed of the vehicles. So she was a patient who was missing the ability to perceive motion because this area was damaged in her. Milena’s almost the opposite of that.
he’s missing most of the rest of her early visual system and yet she’s got this area that can still perceive motion and that area that can perceive motion has a lot of connections with other areas in the brain that can do things like reaching and grasping and navigating and so on, and so that’s why we think she’s been able to use some of these residual abilities in order to do those kinds of daily functions.
Gawrylewski: Hmm that is wild.
Lewis: Yeah that is really fascinating. It’s almost like just seeing the world in strobe.
Gawrylewski: I was exactly thinking that, like, a strobe.
Culham: The old patient, that’s how they describe it, if you’ve been, say, to a…well, a disco or something where there’s a strobe light and you’ve seen how you know everything looks like it’s just a series of still frames and if you ever do that you can try doing something like have somebody toss something at you and you’ll have a really hard time catching it because you can’t gage the motions. So for this other patient who’s like the opposite of Milena that’s kind of what the world that she experiences is described like. I think one thing that’s important to note and this is something that our colleague Gordon Dutton is quite passionate about is just raising peoples’ awareness both in the public and even in the medical community that vision isn’t just one thing so those of us with normal vision have this that it seems so effortless, we just open our eyes and the world is there and everything about the world that we’re used to is there. We can see the form of objects, we can see how they move, we can see the color and the texture and all of these rich things. And so we tend to assume when we hear about patients who are bind that the world is just gonna be black to them and they’re not gonna see anything. And in Milena’s case and other cases like her, we see that sometimes patients could have certain types of vision but not others.
So I think that’s really the most interesting thing about Milena is she opens up a lot of possibilities for future things that might be able to be done to do therapies for patients how have visual loss because of brain damage to enable them to learn to take advantage of some of the residual abilities and the residual connections in the brain that may still be present.
Lewis: That’s really an amazing case and it’s just wonderful that Milena was so willing to give her time to make this study possible.
Culham: She’s a really wonderful woman. She’s stayed very positive about everything over the years. She’s been incredibly generous with her time, for her and her family to come to Canada and the Netherlands and travel around to do all of these crazy tests that we do. So we’ve been super-grateful to her for helping to shed some light on what can happen in these fascinating cases.
Gawrylewski: Thanks for listening to the new Scientific American podcast. We’ll be back soon with another episode. Meanwhile, get your science-news fix at our Web site, www.scientificamerican.com and follow us on Twitter where you’ll get a tweet whenever a new item hits the Web site. Our Twitter handle is @sciam. For Scientific American, I’m Andrea Gawrylewski.
Lewis: And I’m Tanya Lewis.