MS. DIANE REHMThanks for joining us. I'm Diane Rehm. Service and therapy dogs are especially trained to help people. They've gone to Newtown, Boston and West, Texas to provide comfort in times of crisis and tragedy. Brian Hare of the Duke Canine Cognition Center is here to explain why the relationship between dogs and humans is unique in the animal kingdom, also Amy McCullough of the American Humane Association and Paul Mundell of Canine Companions for Independence.

MS. DIANE REHMI know many of you love dogs and will want to join us, 800-433-8850. Send us your email to drshow@wamu.org. Follow us on Facebook or send us a tweet. Good morning and welcome to all of you.

MR. BRIAN HAREGood morning.

MS. AMY MCCULLOUGHGood morning.

MR. PAUL MUNDELLGood morning.

REHMAmy, I want to start with you because I know you were in Boston last week with your therapy dog Bailey. Tell us about that.

MCCULLOUGHYes, well, like all Americans, when we heard the news of the Boston bombings, we wanted to help and so the American Humane Association authorized Bailey and I to travel to Boston and we spent two days there. This was approximately a week after the bombings.

MCCULLOUGHAnd the first day that we were there, we spent the bulk of the day at the two bomb sites. It was the first day that they had opened back up Boylston Street and there were two makeshift memorials set up at each of the bomb sites.

MCCULLOUGHAnd so when Bailey and I stepped on to that street, wow, the powerful emotion. I mean, the feeling was palpable. Here's this busy, metropolitan street with dozens, hundreds of people, yet a silence and a weight. And so when Bailey and I approached the first memorial, people started to approach us.

MCCULLOUGHThey would notice Bailey and soon people are sort of forming a semi-circle around Bailey and she's going from person to person wagging and people are petting her and the emotions that I felt and heard from the people was -- it was just so powerful.

MCCULLOUGHSome people were silent, but tears running down their faces as they petted her. Other people had questions about Bailey and then some would talk about sort of what they were feeling at that point. There was a man who said that he had come there that morning to the memorial specifically because he had a son who had passed away from cancer when he was about Martin Richard's age and so he felt moved to come there to the memorial and pay his respects.

REHMTell me what kind of dog Bailey is and what kind of training she's had.

MCCULLOUGHShe is a golden retriever and she has been trained through a national organization called Pet Partners. And so she and I had to complete training and she goes through an assessment every two years to make sure that she still has the skills and aptitude to be a therapy dog.

MCCULLOUGHSo while we were there, we also looped in with a local group called Tufts Paws for People and they put us in touch with a couple of other organizations so we could visit some other people, like the first responders we spent time with. We spent some time at a counseling session for the race volunteers and so it was really an amazing two days while we were there.

REHMAmy McCullough, she's national director of animal-assisted therapy for the American Humane Association. We've got lots of pictures on our website drshow.org of Amy and Bailey and of canine companion dogs so you can see them all there. Paul Mundell, one of Canine Companions' dogs also had a job in Boston. Tell us about Wenna (sp?), a three-year-old black Lab and golden retriever cross.

MUNDELLYes, yes, well, Wenna was there with. Wenna is a Canine Companion graduate, as you said, and she was there with her handler, Laurie (sp?) who lives in the Boston area. And normally, Laurie and Wenna are victim advocates. They work children and victims of crime and Wenna provides comfort.

MUNDELLAnd so given the tragedy in Boston, I mean, as Amy just described, you know, these are the times when the magic that dogs can express is so needed.

REHMWhat is that magic?

MUNDELLWell, you know, that's a great question and that's what we spend a lot of time thinking about in the Canine Companions, what we try to, you know, facilitate. And, you know, I think it's unique to dogs, the kind of empathy that we feel for them and we believe that they feel for us is something that is exclusive in all the creatures around us.

MUNDELLAnd I think that, you know, one of the things that we try to do is through breeding and through training and socialization and, of course, training of the handler who is going to be working with the dog, try to kind of get minimally get out of the way of that magic, so to speak.

MUNDELLIn other words, get it so the dog is comfortable in any environment and is not, you know, has the sort of temperament that's it is going to be happy doing it.

REHMAnd what kinds of folks does Wenna work with ordinarily?

MUNDELLSo day in and day out, Wenna works with people who are the victims of crime, you know. And very often, especially in the case of children, as we all know, you know, when they've been subject to trauma, you know, and feeling threatened already, relating to strangers, particularly strange adults, it's not the easiest thing in the world. And there again, I mean, that's what dogs enable. They, you know, children will interact with Wenna in a way that they won't with strange adults.

REHMPaul Mundell, he's national director of canine programs for Canine Companions for Independence. Now turning to you, Brian Hare, you are the co-author of a new book titled "The Genius of Dogs: How Dogs are Smarter than You Think," and I have always known that. But tell me what that title implies?

HAREWell, I think what's exciting for dog lovers everywhere to know is that science has finally woken up and realized what everybody has known already, which is that dogs are geniuses and that they're really important to study and that we can learn a lot about animal psychology and even human psychology if we understand dogs better.

HARESo about ten years ago, what people would have said about dogs is, well, why would you study a dog? They're totally unremarkable. They're just a normal mammal. Yeah, we have them, but they're artificially selected, et cetera.

HAREBut what happened a little over ten years ago is we discovered that dogs have an unbelievable ability to, relative to other species, relative to wolves, relative to great apes...

REHMCats?

HARE...cats too, relative to cats, to understand us in terms of our gestural communication, to respond to, you know, spoken words, to also potentially respond to how we're feeling et cetera. And one of the most fun findings really, and this is all scientifically demonstrated, is that dogs actually really prefer people to dogs and so that's...

REHMReally?

HAREYes, and so people have actually done the studies where you give dogs the choice. Do you want to hang out with a dog or do you want to hang out with a person? And the answer is they want to hang out with people.

REHMBrian Hare, he's professor of evolutionary anthropology, director of the Duke Canine Cognition Center. He's co-author of "The Genius of Dogs" and co-founder of Dognition. Tell me what Dognition means.

HAREWell, Dognition is really exciting because basically because we've learned so much about dogs, now we have the opportunity to provide people at home, to actually use some of the science through Dognition.com to play games with their own dog. These are cognitive games, to not find out how, whether your dog is smart or not. I can tell you if you're listening to the show and excited about dogs, then your dog is already a genius because it's convinced you that you should take care of it.

HAREAnd so what Dognition is about is helping you understand your dog as an individual. Is your dog one that has a lot of empathy relative to other dogs? Is your dog a dog that's very communicative relative to other dogs? Is your dog a dog that has remarkable memory? Is it a dog that is capable of reasoning? Is your dog one that is perhaps a little too cunning, i.e. it sometimes uses its intelligence against you?

HARESo Dognition helps you play some of these games to actually understand more about what dog you're living with. Just quickly, my own dog when I tested him...

REHMWhat kind?

HAREHe is a Majorca (sp?) , he's an American black dog. He's from the shelter.

REHMOkay.

HAREHe's very rare.

REHMSmall dog, big dog?

HAREHe's a big dog. He's a big dog and he knows it. And so I play Dognition with him and I'm an expert. I do this for a living and I thought, okay, he's not going to be particularly empathic and he's very communicative, but inferential reasoning, no way. And he completely did exactly the opposite of everything I predicted and so I didn't know my dog as well as I thought I did and that's what Dognition.com is all about.

REHMNow Nancy Robertson, a producer on this program, went to do this with her very own dog.

HAREUm-hum.

REHMShe said you really need two people to do this.

HARERight, so if your dog is really good at sitting and staying, you can do it on your own. But if you're looking for a fun date with somebody you know that might enjoy dogs together with you, this is a great opportunity to spend some time with people you care about.

REHMBut why would you need a second person?

HAREOh, you only need a person if your dog can't sit or stay because somebody has to hold the dog while you're playing the games and then let them go to make their choices.

REHMAll right, Brian Hare, Amy McCullough, Paul Mundell they're all here to talk about dogs as therapy dogs, dogs as comfort dogs, dogs as genius dogs. We'll take a short break here and I hope you'll join us. Go to our website drshow.org see the pictures, give us a call. I look forward to speaking with you.

REHMAnd we have lots of callers waiting. We've got lots of emails. Here's one from Candy in Freeport, IL. She said: Just saw the documentary, "Shelter Me," please talk about the programs that provide dogs to be trained as service dogs via correctional facilities. This documentary show what must be a wonderful program for inmates as well as providing the animals to the people in need of them.

MUNDELLI can't speak specifically about that program. Although I can tell you that many programs, including Canine Companions use the prison programs as either part of this we do, part of the rearing process for some of our puppies. Some of the programs use inmates as kind of the trainers as well. And, you know, the way -- certainly the way we view it, you know, for those prisons that, you know, are part of the kind of Canine Companion's puppy-rearing scheme, in many ways it's a double benefit.

MUNDELLI mean, obviously we're getting dogs that are well-socialized, well-trained. But at the same time, the prison inmates are getting kind of a meaningful activity they can do. You know, the reports that we get from them is that, you know, they find it very rewarding because they feel like, you know, in many respects, they are contributing something positive and not kind of just sitting with dead time, but they're actually doing something to benefit people.

REHMPaul, can you clear up the terminology here, therapy dog, care giving dog. You know, all kinds of different designations.

MUNDELLI can certainly try. Yeah, I think, you know, the clearest -- you've got the sort of traditional designations of, you know, guide dog or dog guide, more properly even, service dog, which is typically a dog that's working with somebody with some sort of mobility impairment, if they happen to be in wheelchair. Then you've got therapy dogs, those are dogs that work in kind of a wide variety of situations.

MUNDELLYou know, similar to what Amy was describing, a particular kind of type of therapy dog, it's a Canine Companion's facility dog or other schools like (word?) also used that terminology. Facility dog is a therapy dog, so to speak, that's had certain kind of training and works with typically a professional, kind of some therapist that does that as part of their career. Hearing dogs or signal dogs as the older designation for dogs that work with deaf or hearing impaired people.

MUNDELLComfort dogs is something newer and is a kind of a subset, you might say, of a therapy dog. It's a dog that, you know, is like the Newtown or Boston dogs are often referred to as comfort dogs. In other words, they are, as the name implies, giving comfort to victims of trauma.

REHMSo, Amy, there's got to be a different set of standards, different approach to training for each of these designations.

MCCULLOUGHThere should be. And there are different levels of service dogs depending on the certifying body. There's a few different organizations that certify or register therapy dogs. And some of them do have different sort of levels. For example, with Pet Partners, they have a predictable rating and a complex rating.

REHMWhat does that mean?

MCCULLOUGHIt's to describe the type of setting that the dog will be performing animal-assisted therapy within. So it has to do with the population that they'll be working with. It has to do with the amount of staff intervention that is at that facility, and then the goals of the interaction. So you're looking at a different dog that might go into an intensive care unit and be working with frail elders versus maybe a dog that goes to a youth correctional facility and runs outside and plays with the child.

MCCULLOUGHSo there are definitely different applications that these dogs are used in. And so it's incumbent on the facility primarily to ensure that they have policies and procedures in place to make sure that the dogs that they are inviting in to serve their population are qualified and a good fit.

REHMAnd I wonder what that means. For example, if you, is there a certain breed that's more likely to be amenable to this kind of training? For example, as a hearing dog, Brian?

HAREWell, I mean, actually Paul would be the expert on how you train these dogs and why different breeds have been chosen for the purposes that they're being used for. But I think, in general, you know, one of the things that we found in our research -- one of our projects is funded by the National Institutes of Health, they actually work with CCI, the Canine Companions for Independence o help them even come up with better ways to identify dogs that will be appropriate for the different jobs they do.

HAREAnd I tell you, one of the first things that you notice is the temperament of these dogs seems really different than your normal dog.

REHMHow so?

HAREJust incredibly calm and sort of almost stoic, in a way. And, you know, really nothing bothers them. And so, they can handle a lot of stress and they are not gonna be bothered or even attracted to things that -- my dog, you know, if there's another dog, my dog wants to go meet it. And these guys, they're really concentrating on what they're there to do.

REHMCan you tell from puppyhood whether a dog is going to have that kind of temperament?

HARESo they -- so Paul has some great tests and different organizations use tests to do this. And part of our job has been, can we do even better? So, Paul, maybe you -- I don't know if you want to speak to that.

MUNDELLSure, sure. Yeah, the, you know, that kind of early predictive tests is, in many ways, the holy grail for us because we have all of these dogs and you want to know which ones to devote resources to and which ones not. And, you know, certainly the dogs that are either going to be stellar at the work or are going to be treated kind of failures at the work, those are detectable early on.

MUNDELLBut there's a broad kind of middle range and that's where -- that's been where we're really devoting a lot effort. With Brian and with the Canine Cognition Center to really focus on those dogs that really until they're in training, so until they're, you know, coming up on a year-and-a-half old, you know, we're not sure. Are they going to be good dogs or are they going to have particular characteristics that may make them unsuitable?

REHMSo, it's not until they're about a year and a half old then that you can really tell.

MUNDELLYes, yeah.

REHMAnd until then, they may just act like ordinary puppies.

MUNDELLWell, a lot of the time is spent acting like ordinary puppies. That's an important part of their socialization.

REHMYeah.

MUNDELLAnd, you know, even -- I should add, even when they're working, I mean, when they're not actually working, we want them to act like ordinary dogs and relax and play. I mean, that's an important part of their life. It's also an important part of the bond between the handler and the dog that the dog is -- when it's off duty, so to speak, is relaxing and playing.

REHMSomeone has written an email saying that rescue dogs, mutts from shelters can be trained to do this work just as well and criticizing me saying by asking about breed, you're enforcing stereotypes that these dogs need to be pedigreed and bred for this work. Amy?

MCCULLOUGHI have assessed hundreds of dogs to be therapy dogs. And I found that there are some types of dogs that are more predisposed to potentially being a therapy dog, retrievers for example. But -- and the volunteers that I've worked with, we've seen everything from Great Danes to Chihuahuas and plenty of mixed breeds in between. So it really depends on that dog's demeanor.

MCCULLOUGHAnd although most dogs can be -- many dogs can be trained to be obedient, there's something innate in a therapy dog that they have the propensity to seek interaction with people. And so that's something that we really look for in therapy dogs.

REHMI guess that's what I wondered about. You talked about a year and a half as the beginning point for really understanding whether a dog can move in to that sort of training. The issue is during that year and a half they've been exposed to an owner, hadn't they picked up some of their characteristics not only been exposed to the good but also the bad and the indifferent, Brian?

HAREWell, I mean, truthfully, what we found is that the special skills that we discover that make dogs remarkable, that made science so excited about paying attention to dogs finally, these are things that are really robust. They develop very early. So the ability to understand us, to communicate with us, to really respond to, you know, sort of have an empathetic response, these are things that come online very, very early.

HAREAnd actually we see them across breeds. There's very little that breed explains about this and actually rearing history. So you can, I think, facilitate and, you know, help, you know, build on this. But I don't think some of the core things that make a dog a dog, you know, there's definitely individual variance. But it's not necessarily determined by breed.

REHMIs there any real truth to the fact, to the idea that there are no dumb dogs?

HAREWell, I mean, that's what we argue in the book. The genius of dogs is because if you think about where dogs come from, so there have been dogs about 12 to 15,000 years ago and wolves were their ancestor. And one day, some wolves decided to start hanging out near people and eating garbage. And that actually created selection, natural selection. It's not that people domesticated dogs, dogs -- wolves decided to start hanging out near people.

HAREAnd they started eating out garbage, which is a much more reliable source of food. And as a result, they were altered forever by that because it's only a certain wolf that could do this. And so those wolves bred together, it made them friendlier. And we know from experiments on lots of different animals, if you have selection for friendliness, you have a whole bunch of changes. Like you end up with fluffy ears and curly tails.

HAREAnd your coat color changes, et cetera. So imagine the relationship with wolves 15,000 years ago. If you think it's controversial today, I actually think there will be a lot less controversy. I think any human that you met 15,000 years ago would hate wolves because they eat what you eat. They're a direct competitor. And so the fact that basically a population of wolves was able to not only start relying on humans but then actually now have evolved into what we all have at home.

HAREAnd keep in mind that most of the breeds are only about 150 years old. So the fact you have the -- all these animals that even sleep in your own bed but they evolved from wolves that, you know, even today are, you know, not particularly beloved and it, you know, they don't live in a lot of place where humans live. So, I mean, what a coup for that population of wolves that decided to hang out with humans.

REHMBrian Hare, he's professor of evolutionary anthropology, director of the Duke Canine Cognition Center, co-author of the new book titled, "The Genius of Dogs: How Dogs Are Smarter Than You Think." And you're listening to "The Diane Rehm Show." In your book, you tell lots of stories, but there's a study in Japan that sort of knock my socks off. It's about intestinal cancer.

HARERight. So there's a dog that's been trained to smell breath. It can smell your breath and it was as effective as a colonoscopy at detecting whether you had intestinal cancer. And so, next time you're at the doctors, just raise your hand and say, dog please. Because I would much rather have the dog smell my breath than have a colonoscopy. So hopefully, this will be the future.

REHMAre there other cancers that dogs seem to be able to detect?

HAREYes. This is an active area of research. And, you know, and all of these different dogs that are -- and first thing to emphasize is dogs have more jobs than ever. I listen to your show all the time and it's -- the Great Recession was horrible and there's been a lot of suffering. But dogs in the age of the iPad and the internet actually have had a jobs boom. There are more jobs for dogs than ever.

HAREAnd so, because there are all these new jobs, researchers are trying to actually figure out how do they do it? Are they actually doing anything? And how do we increase the supply? But then back to cancer, the answer is, the one that's really well established is the detection of melanomas. So dogs are very good at detecting melanomas. There's a...

REHMAgain through smelling the breath?

HARENo, actually smelling the skin cancer on your body they can detect if the, you know, the spot is...

REHMHow widespread is that being known or used?

HAREWell, I think that, you know, just like anything with the medical community can't take this on board as a serious technology until it's very well established. And I think that the literature is becoming clear that it works. And now the question is, and this is very recent, in the last couple of years it's become clear. And so now the question is, is this something that makes economic sense? And can we train enough dogs to serve enough people? But certainly dogs can detect melanoma.

REHMAnd to you, Paul, I know Canine Companions has a puppy breeding program.

MUNDELLYes.

REHMBut why are they all goldens or Labrador Retrievers or a mix of the two?

MUNDELLIt's those breeds, you know, start out with a lot of the characteristics that we would like in service dogs. They, you know, aren't anxious typically about strangers. They're not the sort of dog that just bonds with one person to the exclusion of other people. You know, our dogs are, you know, if they're with you, they're bonding with you and they love you. But, you know, when it's time for them to go from, say, to puppy raiser to training, or then from training to the graduate they're going to be partnered with, you know, they'll make that move within nanoseconds seemingly.

MUNDELLI mean, they bond very quickly to new people. They're pretty unflappable in many environments. And so they form a great -- and of course physically just in terms of their size and their health and their life spans. They work very well in those...

REHMLet me ask you about that health and life spans. Is it true that more goldens are developing cancers?

MUNDELLYes, it is. And, you know, goldens have emerged, I mean, in terms of dogs with jobs and dogs as models. Golden Retrievers, unfortunately, have become models for cancer diagnostics and therapy and research just because goldens suffer pretty much the same cancers that humans do and in a rate that's fairly high.

REHMAnd is that fairly recent?

MUNDELLYou know, that's a good question. It appears to be. Now to what extent some of that is just increasing diagnostics is unknown. But it probably is the case that the frequency is increasing.

REHMPaul Mundell, national director of Canine Programs or Canine Companions for Independence.

REHMAnd welcome back as we talk about dogs in the full range of their wonderful capacity there is a question here which, I'm sure, affects lots of people says, "How would you reconcile the idea of comfort/service dogs and people like me who are afraid of dogs?" Amy.

MCCULLOUGHRight. This is where the other end of the leash comes into effect. And that's the handler, the owner of the dog.

REHMOf course.

HARESo part of the training to be a therapy dog handler is to ensure that you receive permission to approach with your dog because we know not everybody is a dog person. And so we want to respect people who have the right not to interact with a dog as well.

REHMI have to go the other way. I have a small long-haired Chihuahua who is adorable. Everybody wants to pet him. And I say to them let him come to you. Do not lean over and put your hand on his head because he's likely to take your finger off. I mean I think it has to be a two-way street, Brian.

HAREWell, there's a really cool new initiative called the Yellow Ribbon Program where if you have a dog like that they're trying to, sort of, have a new norm be that you tie a yellow ribbon to the leash of your dog or to the collar. And so that everybody can know if your dog has a yellow ribbon this is a dog that you need to let approach you or talk to the owner before you touch them. And, you know, my dog's the same way. We have a yellow ribbon on our dog when we go out.

REHMYou do?

HAREOh, yes, yes, yes.

REHMInteresting.

HAREAnd, you know, there's...

REHMGreat idea.

HARE...There's nature versus nurture and, you know, it's not -- or, sorry, I should say nature and nurture. It's not nature versus nurture. Nature and nurture and so it's not an owner's fault that your dog is that way. A lot of dogs are just -- that's the way they're tuned.

REHMExactly.

HAREAnd, you know, obviously you have dogs that were reared in a way that make them more aggressive, but it's an interaction of nature and nurture, but we can solve it all if people just put a yellow ribbon on their dog. And if people knew that's what that meant. It's a great initiative.

REHMAnd what I do is say to people let him come to you. And invariantly he will if he feels safe with that person. Instinctively they know with whom they can feel safe. Otherwise he doesn't go. Let's go to Miami, Fla. good morning, April, you're on the air.

APRILGood morning. I was a puppy raiser for Southeastern Guide Dogs. I raised the seeing eye dog puppy. And through that wonderful experience I decided to make my dog -- the subsequent dog, a German Shorthair Pointer, a therapy dog. And Erma is 18 months old and she is a reading education assistance dog. And what that means is we go into libraries in schools where children who are struggling reading aloud get to lay down with Erma on a special bed and read aloud to her in a very nonthreatening manner where she won't criticize the way they pronounce the word or they -- they're allowed to just read and enjoy reading.

APRILAnd it seems the children look forward to it every week and mothers have said it makes their child want to read more and want to bring a book and what book am I going to read to Erma next week. So I found it extremely rewarding. And she's a hunting dog so not a typical therapy dog.

REHMWow. Brian.

HAREWell, I think that caller raises, you know, just makes the point how many jobs dogs have now. And my job as a scientist, of course, is to be skeptical and ask the question is it -- these jobs that dogs are doing are they actually doing anything. And I think basically in the book, as we review the literature, the answer is overwhelming yes. And so one of the exciting things to go forward is, for instance, a reading dog. What is that reading dog actually doing?

REHMYeah.

HAREYou know, let's do some research and figure should we have reading dogs in every library or That only some dogs can do it or that only some kids are affected. And, you know, how can we perfect this even better. So the fun one at Duke is that they're -- during exam time they're exam dogs. And there's a real...

REHMTo help calm people down?

HAREExactly. There's a room in the library where you can go and hang out with puppies and dogs because one of the things that has been established is that people who interact with dogs have a rise in a hormone that basically makes you feel more social and a decrease in the hormone that makes you feel stressed out.

REHMAmy.

MCCULLOUGHBailey and I were just at the University of Colorado medical library on Sunday to provide some stress relief for med students during finals week.

REHMReally.

MCCULLOUGHSo, yes, and like Brian said the research isn't there. I mean studies regarding animal assisted therapy date back to the '70s, but yet there's not enough rigorous science behind that. We all know anecdotally that these dogs are good for human health and well being, but the science has really lagged behind. And so that's why American Humane Association has just launched a research study called Canines and Childhood Cancer where are implementing a randomized controlled trial across multiple Children's Hospitals to look at whether children who visit with a therapy dog during their chemotherapy sessions experience less distress than children who do not.

REHMOh, wow. Just extraordinary, thanks for calling, April. Let's go to Sherry in St. Louis, Mo. Good morning, you're on the air.

SHERRYGood morning. I was calling to say that a while back I met a woman who had just moved to St. Louis from New York City. And she moved here with her family and two dogs. Well, our kids were about the same age so we hit it off really well. She didn't live very far from us, about a mile, mile and a half, so we always visited each other's house and the kids played there. Well, about four months after she lived here her dogs started to chronically escape the yard. And my friend was always going out, getting the dogs and then bringing them back to her house.

SHERRYWell, during this period I was sitting at my home alone and I'm sitting at my kitchen table and I heard a noise at my door. And I got very frightened because I didn't see anyone. Finally, I got up the nerve to go to the door and I looked out the window and there were her two dogs pawing at my door. And they had never been to my house. And I was certain that they were purposely pawing at my door. And I opened it up and they came right in and they sat down like they were ready for a treat. And I sent her a picture of them, look who has visited my house.

REHMOh, my goodness. Well, dogs do have a sense of direction.

HAREWell, so we -- so that story is a beautiful example of, you know, the excitement of doing science on dogs or with dogs is that there's a lot we don't understand and a lot we don't know. And so if you ask me how did the dogs do that as a scientist, well, I'm supposed to know that because I'm mister fancy scientist person. I have no idea.

REHMYeah.

HAREAnd to be honest, you know, and that's part of the fun is there's a lot of mystery.

REHMSure.

HAREThere is some things that seem a little bit magical so the -- I think that's one of the reasons it's so exciting that scientists are now excited about dogs.

REHMExactly. Here's an email, let's see, from a person who says, "I have MS and use a service dog for mobility assistance. Are therapy dogs covered similarly under the ADA or are requirements different?" Paul.

MUNDELLWell, let me first give the disclaimer that I'm not an attorney and so I'm giving you my opinion in reading.

REHMSure.

MUNDELLBut they're different. The Americans with Disabilities Act, which was further clarified in 2010 really specifies that -- well, first of all, the Act applies to humans, not to dogs. And so by definition the dog that's covered under the ADA is covered because they're with a human. So it's the person that the law is really applying to not the dog. And so if you think about that in that context you realize that, like, a service dog or a guide dog because they're helping a person with a disability, kind of, mitigate those problems.

MUNDELLThey've been individually trained as the law states to help -- to do certain behaviors to help with the problems that a person with a disability may have. That's -- it's by virtue of that that they're covered under the Americans with Disabilities Law and have access. Now a therapy dog doesn't meet those criteria and so it's not covered under that law.

REHMAnd what about a comfort dog?

MUNDELLThe comfort dog under the ADA is considered the same as a therapy dog. Now we should say, as we were discussing earlier, the caveat there is that local ordinances may change that.

REHMAnd the law is evolving.

MUNDELLExactly.

REHMYeah. OK, let's go to Elkridge, Md., Cecilia, you're on the air.

CECILIAYes, hello.

REHMHi.

CECILIAI am an army occupational therapist who was fortunate enough to deploy to Iraq with a therapy dog. We responded to many traumatic events, but the one that I particularly remember was an incident in which five service members were killed. The eve of that event myself and my dog who actually had a rank. She was Sergeant Beaux (sp?). We responded to the event with some other mental health providers and a chaplain. I remember waiting outside -- waiting to visit the unit that had been affected when a young sergeant came out and she kindly asked everyone to leave. She basically said they just wanted to be alone.

CECILIAAs we started to walk she turned to me and she said, ma'am, you and Sergeant Beaux can come in. And we went in that night and I'll never forget it. And I think they really did not want to talk. They kind of just wanted to mourn for a little bit, but having the dog there was a very -- it was almost a comforting thing for them. And I just think that that's a very good example of what a therapy dog can do in a traumatic situation -- a traumatic event.

REHMAnd we have an email from Cindy who says, "What about the role dogs are playing helping people in the military who are dealing with PTSD, anxiety and depression." Cecilia, I want to thank you for that call and for telling us that story. I'm so moved. What about the VA? Is it recognizing the role that dogs are playing, Amy?

MCCULLOUGHRecently there was a study that the VA was conducting regarding therapy dog or service dogs with returning veterans of PTSD. They've since stopped that study and American Humane Association has called for them to reopen this and look at this because these service members are definitely in need of help. And there are great organizations that are ready to provide service dogs along with CCI and American Humane Association for these veterans. And so it's a problem that needs to be corrected.

MUNDELLYeah, exactly. And I'm happy to say it really does look like the VA will restart that study. There were some methodological problems you might say with the way that the study was initially designed, but it looks as though it's going to be relaunched and we're hopeful it'll bear fruit.

REHMAnd you're listening to "The Diane Rehm Show." I don't think that this is joke, but Ann in Indianapolis I gather you have a rather unusual therapy animal.

ANNGood morning.

REHMGood morning.

ANNThis is so exciting to be on your show, but, yes, I do. I have Harley, he's a pot-bellied pig. And he was evaluated by Pet Partners this weekend and he -- somebody mentioned the ratings earlier. That they can be predictable or complicated environments so he was evaluated as being able to work in a predictable environment so -- I'm a social worker. I work with clients with developmental disability and mental illness so he'll be working with me and with my clients and going into group facilities during the days and...

REHMWell, Ann, tell me what the reaction is from the people who see this pot-bellied pig. How much does the pot-bellied pig weigh?

ANNHe's about 35 pounds.

REHMThirty-five?

ANNHe's about the size of our puggle. He's not very big.

REHMI see. And what does he do?

ANNHe just delights everybody. He makes little grunting noises and if you scratch his belly he falls over and he rubs against people and he takes snacks very gently from their hands. And he'll walk with people and...

REHMI can't -- I can't resist asking you what's your pot-bellied pig's name?

ANNHarley.

REHMIs Harley housebroken?

ANNHe is.

REHMSo he's...

ANNHe sleeps with my son at night.

REHMI thought so. I thought so.

ANNYeah, he's totally a house pig.

REHMYeah.

ANNUm-hum, he just goes out to go to the bathroom.

REHMNow it seems to me, Brian, you are going to have to expand your anthropological studies to take into account -- this not the first pot-bellied pig I've heard about.

HARERight. And the thing to know about pot-bellied pigs, just to be clear, so don't everybody go run and buy one now because they actually can be hundreds of pounds by the time they grow up. So don't be surprised when your little pot-bellied pig gets really big. But they -- yes, I mean domesticated animals I've seen llamas are being used. You know, obviously, this person's using pigs to great effect. And so while dogs are used very, very effectively it doesn't necessarily mean they can corner the whole market. And -- but I would say that I'm not aware of any research on other animals besides dogs being used in this way. That doesn't mean that they aren't effective.

REHMExactly.

HAREIt does not mean that, but it just means we don't know.

REHMWe don't know and yet clearly Ann has experienced something that not only she finds valuable, but the people around her do. All of which says to me that there is a far closer relationship between us and the animal world than we had any idea of. Dogs because they live with us so frequently are the ones we study. But I'll bet eventually, perhaps not in my lifetime, but in yours you may find really strong connections. Amy, any last words?

MCCULLOUGHYes, I wanted to say that, of course, dogs are most prevalent therapy animal, but there are other breeds, or other species, that do. There are therapy cats, goats, llamas, miniature horses, chickens, rats so, yes, there's room in people's hearts to love all these kinds of animals.

REHMAll right. We'll leave it at that. Thanks for your call, Ann, and take good care of Harley, your pot-bellied pig. Amy McCullough, she's national director of animal-assisted therapy for the American Humane Association, Brian Hare is professor of evolutionary anthropology, author of "The Genius of Dogs" and Paul Mundell, national director of canine programs for Canine Companions for Independence. Thanks for listening all. I'm Diane Rehm.