The Truth about Cats and Dogs
文章来源:未知 文章作者:enread 发布时间:2023-08-07 02:54 字体: [ ]  进入论坛
The Truth about Cats and Dogs
Scientific American magazine Editor in Chief John Rennie talks about the contents of the June issue, including articles on the evolution of cats and the physiology of sled dogs. Plus, we'll test your knowledge of some recent science in the news
Full Transcript
Podcast Transcription
Steve: Welcome to Science Talk, the weekly podcast of Scientific American posted on May 29th, 2009. I'm Steve Mirsky. This week, we'll talk to Scientific American Editor in Chief John Rennie about the contents of the new June issue. Plus, we'll test your knowledge about some recent science in the news. And so without any further ado, here's Johnny.
Steve: The June issue of Scientific American is upon us.
Rennie: Yes. What is so rare as a day in June?
Steve: Sometimes, say, a day in late May, maybe early July.
Rennie: That's right.
Steve: But we have something for the kitty lovers out there...
Rennie: ...Here kitty kitty kitty...
Steve: the current issue.
Rennie: Yes that's right.
Steve: The taming of the cats.
Rennie: Yes, pom pom pom. Yes. This is a story about the origins of the domestic house cat.
Steve: And there are many millions of them across the country, perhaps some of them are even listening to this podcast.
Rennie: Indeed, but if they are listening, you know they are not going to take directions.
Steve: No they won't.
Rennie: It's just the way they are.
Steve: So this is a fascinating article. Now, for the dog people out there, rest assured, we have something for you in this issue as well, and we'll get to that, but let's start with the kitties.
Rennie: Yes, indeed. What this article on the taming of the cat concerns is a new set of work based on genetic analyses of cats and also archaeological studies that are pushing back how early it looks like we actually started domesticating cats. The old idea was that domestication of cats probably started about 8000 years ago back in early Egypt, but the latest evidence suggests that in fact it actually started a couple of thousand years before that, and so as such that's really, quietly significantly revising the sense of how long we and cats have been having little household[s] together.
Steve: We have a grave from Cyprus, was it, that dates back about 9500 years that ...
Rennie: ... that's right.
Steve: There's a human being and presumably the pet cat buried in the same area ...
Rennie: Yeah.
Steve: ... and in the same orientation.
Rennie: So that tends to suggest that even then as you say 9500 years ago that people and their pets were seen as having a close enough connection that it was sometimes seen as appropriate that people and their pets would be buried together.
Steve: Now cats, as the article says, they [don't] really do much for people.
Rennie: Right. Well, this is sort of an interesting issue. [It goes to] your definition of what's involved in domesticating an animal like a cat. Because I think [a] lot of [times] people think domesticating them means we went out we took the original wild ancestors, and we sort of broke them to our ways, you know, did the equivalent of animal enslavement. And, you know, The reality is, all that domestication really means is that we took control of their bloodlines and, as such, you know, they are used to living in close concert with us. But, in fact, in this case, the cats may have basically elected on their own to start living with us. In fact, this goes to sort of the sense of how it is that the origins of the domestication of the cat seems to be started over in the Fertile Crescent and basically right around [the] time that we had the origins of agriculture. And it makes perfect sense, because origins of agriculture, people starting to grow grain and stockpile it; well big surprise, if you start stockpile grain, there is a very good chance that mice and rats, other little vermin will start trying to go after the stockpiles of grains; and where there are mice there soon will be cats. So the cats basically came around to get the mice, and the people found that they were very helpful and sort of encouraged them to stay.
Steve: But other than that, I mean, as opposed to a dog, you can have hunting dogs, you can have, what other services the dogs provide?
Rennie: Well, you know, [that's true]. It's hunting, it's sniffing, companionship more generally, you know there are seeing-eye dogs.
Steve: Right.
Rennie: ... for example, guides ....
Steve: But your cat other than being a mouser, it's not much of a help around the house.
Rennie: No. That's true, basically.
Steve: And yet we love them.
Rennie: Yes.
Steve: We humans.
Rennie: Indeed we do.
Steve: My own cats, well I have two, have brought in—you know, speaking of being mousers—in the last month or so, they have brought home a mouse, a snake, we still have wild snakes in New York City folks!
Rennie: You live in the Bronx?
Steve: I live in the Bronx which is very wooded in certain areas—actually, my area is one. So I stepped on something in the middle of the night recently, very lightly. Once my foot touched something that didn't feel like floor, I drew my foot up very quickly, and when I turned the light on, well there was about a foot-and-a-half long snake in my house that one of my kitties had brought in, and I took the snake, which was still alive, outside. I put him in some foliage, and the next evening he was back.
Rennie: (laughs)
Steve: He was back in the base of my driveway and he was fully dead this time.
Rennie: Courtesy of the cats?
Steve: Well, clearly one of the cats went back and got him and brought him back and said "No, no, no, this one['s] is for me." And so we had the mouse, the snake, and an unfortunate baby bird that probably had fallen out of the nest first. That one I found on the floor of the kitchen, and it's breathing!
Rennie: (laughs) And it definitely was not a slipper.
Steve: Good and so we scooped that up and brought that outside as well and anyway I'm sure everybody is fascinated, fascinated by the stories of my cat's mousing-and-other-critters abilities, but you know, this what they do.
Rennie: Right.
Steve: And their concentration when it comes to these kinds of efforts is unbreakable.
Rennie: Yeah.
Steve: It's much higher than when you [try to] get them to, say, to pay attention to you
Rennie: (laughs) Which I've never had any success.
Steve: Right, because you [are] a dog guy.
Rennie: Well, currently yes, but I grew up with lots of cats too and yes cats they choose to spend their time with you. All the old clichés about the differences between cats and dog people—cat people need to be able to tolerate the fact that their beloved pet may show them very little obvious affection, respect; but then that's what it's like being editor here. So, you know.
Steve: So, the cats became part of the human family, if you will, and they clearly descended from wild cats though.
Rennie: That's right.
Steve: And that all happened pretty rapidly.
Rennie: That's right. Yes, what is also interesting is that they're also, all of the common house cats are descended from one population of wild cats. I mean, you can find different kinds of wild cats scattered across much of the old world, different parts of Africa, Asia and Europe. There are a lot of different wild cat populations, but all of the domesticated cats we see today came from one kind of wild cat that just was found in the Fertile Crescent; which tells us something very significant about the fact about how much the spread of the cats thereafter came along with the sort of the rise and the extent and spread of civilization.
Steve: And so we have ourselves to thank for that.
Rennie: Yes, that's right. And the cats, in the sense they have us to thank for it too, but they will show no gratitude.
Steve: It's just not in them.
Rennie: No.
Steve: As I said, I've promised we have something for the dog people out there, and we have a short article in the front of the magazine, where we have the news pieces, about the amazing physical capabilities of high performance sled dogs.
Rennie: Right and in particular one, Larry, [Larry] the sled dog, who [is] a master at winning the Iditarod, which is a fantastically grueling dogsled race.
Steve: It's such an amazing calorie burner, running this thing, for the dogs. A 50-pound dog will consume 12,000 calories a day, which is just slightly more than I do.
Rennie: We've been meaning to speak to you]about that Steve.
Steve: Now, that's an enormous energy intake. You almost have to eat either just solid sticks of butter or be eating constantly.
Rennie: Yeah. I'm trying to remember when Michael Phelps, back around the Olympics, they were talking about the gigantic quantity that he took in, and I'm not sure he was even eating 12,000 calories.
Steve: I don't remember the specific number, but I think it was approaching 12,000, but not quite.
Rennie: So, I mean, it is understandable why it is that some physiologists who are [really] interested in trying to understand this sort of extreme physical performance, would naturally look at something like the sled dogs. Because clearly they've got some extraordinary ability to be able to have that kind of stamina and the ability to able to keep drawing the energy out of what they are eating efficiently, so that they can keep going through these fantastically grueling conditions.
Steve: Not surprisingly it appears that some of them have just an unbelievable concentration of mitochondria in the muscles of their legs.
Rennie: Right. Which is what you'd expect because of course mitochondria are what are responsible for being able to release the chemical energy that fuels muscle action. But what [was] really interesting in this study of the sled dogs, of Larry the sled dog in particular, was the discovery that some of these high performance dogs appear to have the ability to draw fat directly out of their and blood right into their muscle cells and immediately burn it that way, which is a more efficient way than normally what you'd see.
Steve: Which is storing it first in the liver and then recovering it.
Rennie: Exactly. So, basically they've cut out a step, and they are able to, you know, therefore draw on the food that they've very recently consumed. I mean, this is an amazing adaptation, and so they're really trying to understand what's going on with this. Because what is fascinating about it is that it may not just be a simple trait that has evolved in these dogs, in effect, because of the extreme conditions in which they had to perform. There may actually may be a latent quality that lots of mammals, maybe even people, might actually have, if you can coax it out of them under the right kinds of high-performance conditions. So it's very interesting to look at something like that to see, are there any kinds of circumstances in which it's possible for a super high-performance athlete to start to do the same kind of thing?
Steve: Yeah, these dogs were tested every few miles and they would have tiny little pieces of their muscle biopsied, basically, and maybe we need to do that with ultra marathoners, people who go out and run 50, 60 miles at a clip.
Rennie: It's understandable why people wouldn't be lining up for those kinds of experiments.
Steve: The 60-mile run isn't going to be bad enough. Every five miles, we're going to poke you up and rip [out] parts of your leg muscles; little tiny parts, but hey. And also for you dog people, we won't get into it in much detail, but my column in this issue, the Antigravity column, I suggest a modest proposal, if you will; that in order to answer some of the charges of creationists that there is no proof of evolution—we never saw any speciation in action actually happen, well, why don't we just say, the differences dog breeds [are] different species? Because as Jerry Coyne, evolutionary biologist, says in his book, Why Evolution is True, if an extraterrestrial taxonomist came to earth and looked at the fossil remains of many of the different breeds of dog that we all consider a single species, there's no way he would categorize them as a single species. And as I say, something to the effect that, you know, come on, if you're talking about fertile interbreeding, the only way a male Chihuahua and a female Great Dane are going to have any success is if the Chihuahua invests in either mountain climbing or spelunking equipment, and we'll leave it at that. And there's another interesting feature. Oh! Not just one, but just one more that we'll talk about—the Scientific American 10 appears in this issue. So with everything else in our economy, it's shrunk down from, it used to be the Scientific American 50, but now we're at the Scientific American 10, [it's] much more efficient. We're going for a leaner, more efficient Scientific American n where now n equals 10. So tell us what the Scientific American 10 represents, and we'll talk about some of the honorees this year.
Rennie: Sure the Scientific American 10 is an honor roll we put together in which we try to salute certain people who have taken extraordinary steps to try to make sure that new scientific and technological developments seem like they will be in service to try to generally improve the lot of mankind in various ways. I mean, these are people who in some cases are researchers, but in other case[s] they are industrialists [or] government workers or the leaders of nonprofit, nongovernmental organizations. We want to recognize the fact that basically science and technology advances, particularly advances in beneficial ways, not just through the efforts of scientists themselves, but through efforts of people from every part of society.
Steve: So, in addition to the fact that I haven't heard the word industrialist used outside of a Batman comic book recently.
Rennie: Bruce Wayne is not a winner this year, but perhaps next year.
Steve: Who are some of our SciAm 10 o[r] Scientific American 10 winners?
Rennie: Well, for example, one of the people who I guess would fall into the category of industrialist, thanks for bringing it up, is Shai Agassi.
Steve: This is really interesting stuff.
Rennie: And I think this is really a fascinating example. Shai Agassi is the founder and CEO of a company that is called "Better Place" that is involved in trying to develop a new model for introducing electric cars, making electric cars more practical. [You know] the traditional problem that is the, sort of, the big roadblock, if you will, which stopped a lot of electric car development and going forward, [is that], you know, the batteries are a big limiting factor. The batteries you need for an electric car tend to be very, very expensive and most battery technology is such that you have a [fairly] limited mileage that you would actually be able to associate with the cars. They would not be able to go as far as people can with, [say,] a full tank of gas. This tended to discourage people from being interested in a lot of electric cars. Agassi is proposing a new model, a new business model that would get around some of that. Because in effect, when you would buy an electric car, you would not buy the battery. The battery would be some thing you would, in effect, would be leasing or renting from his service and as you are driving down the road, you notice that your battery is running down, you would pull over into one of his service stations, where you would have the option of perhaps recharging, but more importantly you would be able to swap the battery out and put in a brand new ...
Steve: Fully charged ...
Rennie: ... fully charged battery. So that gets you right past the whole limitation of whether or not the battery is actually going to be a run out of juice or what kind of capacity it might have. So it is a radical new way of thinking about all of that, and it's something that is being tested in Israel, I believe, and maybe a couple of other places. And it may be something that may make electric cars much more practical.
Steve: The amazing thing that he has accomplished is actually getting people onboard to build these battery exchange stations, so that there is this nascent network. There is an infrastructure to enable this whole concept to go forward.
Rennie: Right. I mean, infrastructure really is the key in a lot of these things, but in some ways that goes to the really creative, novel way of thinking about this. A lot of us in the past, looking at the problems of electric cars, have seen it as purely a technological problem. But here if they are recasting it and showing [that] the right kind of infrastructure, the right kind of business model, the right kind of other systems that are not specifically technological, can completely change the game on that.
Steve: Yeah. Who [else] do we have in here?
Rennie: Well, certainly, you know, [a] couple of other people that we really salute for the wonderful work that they're doing are two fellows you might have heard of, Bill Gates and Michael Bloomberg. They have recently proposed to put together this $375 million global antismoking initiative. Everybody recognizes that smoking is the leading cause of preventable deaths and lots of other problems with the disease around the world. So there are tremendous benefits globally that could be had by discouraging people from smoking and. So here you have a case of a couple of billionaires who are using a portion of their money to try to fuel these sorts of antismoking efforts, so that's something with potentially huge good health consequences.
Steve: Yeah. Bloomberg is actually pretty interested in public health, and I know that he has given so much money to Johns Hopkins that the school of public health is the Bloomberg School.
Rennie: Oh!!!!
Steve: So I'm sure that wasn't cheap. I see you've given a little nod to our friend, Eugenie Scott here, who has been on the podcast a few times.
Rennie: Sure, Eugenie Scott from the National Center for Science and Natural Education, who has done wonderful work for years in trying to make sure that evolution, is taught appropriately in public schools and to try to discourage the teaching of creationism under any of its various guises as a bad scientific alternative to that. So we thought that was wonderful because, of course, good science education is really [the] cornerstone for all future scientific and technological development. So we really are glad to be able to recognize her for that work. Someone else that we think did some wonderful work is a professor at Rensselaer Polytechnic Institute, Robert Linhardt. He was involved, you may remember from last year, there was the unfortunate scandal involving tainted heparin. Heparin is a blood thinner and an anticlotting agent and it turned out that some heparin that was on the market, turned out to be contaminated and it had come from China. Linhardt, one of his great contributions in this case was that he was able to do the, sort of, the forensic detective work in tracking that back and to demonstrate exactly where [it] was the contamination came in so it could be identified, and tried to protect people that way. But it was also great [is] that Linhardt has actually been involved in trying to develop a completely synthetic source of heparin so that, potentially in the future, you could avoid all of these kinds of contamination problems.
Steve: So that's the Scientific American 10, and that's only three or four of them. We have a few more, Bryan Willson—not of the Beach Boy.
Rennie: No. That's right, that's right. Bryan Willson—this Bryan Willson is actually a professor of mechanical engineering at Colorado State University, and he has been doing a lot of great things about simple, new kinds of technologies that can greatly improve some of the sorts of technologies that are very commonly used in lots of the developing world. For example, there are lots of these little two-stroke engines that are used on, for example, motorcycles and taxis, its very common source of engine. They are very, very polluting. He and his team have developed a kit that can be, sort of, retrofitted on to these to make them much better, much more efficient than they are. And similarly he has also been involved in developing a new kind of little cook stove that also greatly cuts the emissions that come off these sort of wood burning cook stoves and actually makes these stoves more efficient—[they] heat up food faster. So, you know, really great, beneficial things. They are not glamorous, but on the other hand, they are sort of things that hugely improve the qualities of the lives in other parts of the world and that, of course, are very beneficial to the environment, which ultimately benefits everybody.
Steve: You know, you say that they are not glamorous. One of the things that Tom Friedman pointed out in his book Hot, Flat and Crowded, is that when we're really getting into the innovation of new energy-efficient, nonpolluting things, it's going to be real boring, and I think the listeners will agree to that. We've shown that that's really true. But seriously, it's great stuff, and yes, it's not glamorous, it's nuts and bolts, it's important. There's a lot of hard work involved. It's, you know, Simon Cowell doesn't care about this stuff—is that his name?
Rennie: Simon Cowell, from American Idol?
Steve: Yeah.
Rennie: Yes.
Steve: Is it Cowell? And back to Bruce Wayne. But now let me just wrap up our little discussion of the June issue. As you know I'm a big fan of the "50, 100, and 150 Years Ago" column that we keep in front of the book.
Rennie: Who isn't?
Steve: Who isn't? And I would like to share something with you from 50 years ago.
Rennie: A mere 50 years ago this time.
Steve: Just 50 years ago, June of 1959. And in June of 1959, we wrote, "The problems of eating and drinking under weightless conditions in space, long a topic of speculation [among] science fiction writers are now under investigation in a flying laboratory. Preliminary results indicate that space travelers will drink from plastic squeeze bottles and [that] space cooks will specialize in semiliquid preparations resembling baby food. According to our report in the Journal of Aviation Medicine almost all the volunteers found that drinking from an open container was a frustrating and exceedingly messy process. Under weightless conditions, even a slowly lifted glass of water was apt to project an amoeba like mass [of] fluid onto the face. Drinking from the straw was hardly more satisfactory. Bubbles of air remained suspended in the weightless water and the subjects ingested more air than water." And just 50 years later, astronauts, just last week, drank their own recycled urine in space out of, squeezable kinds of, you know, plastic bag kind of things. But a couple of big circular globs of the perfectly portable drinking water now did get loose and I saw some astronauts on television just sort of floating over in revolving their head around and just catching that globule of water.
Rennie: And slurping that up?
Steve: Right. And only in 50 years, we've gone from experimenting with how we're going to eat and drink in space to actually recycling the astronauts' own urine, so that they could drink it [in] space.
Rennie: That's one small step for a man, one giant leap for mankind.
Steve: Check out the other articles in the June issue, including the cover piece and the recent discoveries of improbable planets around unlikely suns. All the articles are available free for nothing for a limited time at the Web site,
Now it's time to play TOTALLY....................BOGUS. Here are four science stories, but only three are true. See if you know, which story is TOTALLY.................... BOGUS.
Story number 1: The recycled water the astronauts drank wasn't just recovered from urine; the purification system also took in sweat and the water vapor in exhaled air.
Story number 2: On May 20th, Scott Parazynski became the first shuttle astronaut to Twitter from space.
Story number 3: On May 29th, the International Space Station population reaches six for the first time with the arrival of three new astronauts.
And story number 4: The bacteria in your armpits are probably more similar to the bacteria in somebody else's armpits than to the bacteria on your own forearms.
Time is up.
Story number 4 is true. Different kinds of bacteria prefer different environments on your skin. So your forearm and armpit bacteria will probably differ vastly, but your armpit bacteria won't differ that much from somebody else's armpit bacteria. The research appeared in the Journal Science and the May 29th episode of the daily SciAm podcast, 60-second Science.
Story number 1 is true. The astronauts' recycled drinking water came from urine, sweat and exhalations. No wonder the water had that certain tang.
Story number 3 is true. The ISS population for the first time reaches six, and for the first time five different space agencies are representing it. For more, read John Matson's article on the Scientific American Web site entitled "Space Station Population about to Double".
All of which means that story number 2, about Scott Parazynski becoming the first astronaut to Twitter from space is TOTALLY.................BOGUS. Because what is true is that on May 20th Parazynski, who last went to space in 2007, became the first astronaut to reach the summit of Mount Everest, a place to definitely avoid any giant leaps.
Well that's it for this edition of the Scientific American's Science Talk. Check out for the latest science news, including Jesse Bering's "Mind and Brain" blog and why girls are so cruel to each other, and our slide show on the top 10 Earth- and people-friendly buildings. For Science Talk, I'm Steve Mirsky. Thanks for clicking on us.
Scientific American magazine Editor in Chief John Rennie talks about the contents of the June issue, including articles on the evolution of cats and the physiology of sled dogs. Plus, we'll test your knowledge of some recent science in the news.