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Science Matters with Lawrence Krauss

Airdate: February 17, 2015
Arizona State University physicist Lawrence Krauss brings us up to date on the latest science news.

Guests:
  • Lawrence Krauss - Physicist, Arizona State University
Category: Science

Keywords: science, lawrence krauss, asu, news,

View Transcript
Ted Simons: A recent discovery is leading researchers to think they may have found a new primitive human species. Here to discuss that and more is our friend, ASU physicist, Lawrence Krauss, who appears every month on our show to educate and illuminate our audience while at times completely befuddling the host. How are you doing?

Lawrence Krauss: I was trying to educate and illuminate you

Ted Simons: I like that shirt.

Lawrence Krauss: What do you think it is?

Ted Simons: They look like jackasses.

Lawrence Krauss: That’s a good guess. That’s normally how accurate you are. They’re zebras.

Ted Simons: Those are zebras, okay. Let's get to humans. New primitive human found --

Lawrence Krauss: Well, yes, maybe, the answer is maybe. What it really means is that we -- we're just learning about our history in many ways. We have discovered there are at least three and maybe four dominant species living all at the same time. Homo sapiens, Neanderthals, and there’s another group called denisovans, a Hobbit group that has been known, but the point is recent discoveries in China. Let me say these groups coexisted between 200,000 years ago and up to about maybe 40,000 years ago. Humans, so that -- Neanderthals first went into Europe, Asia, this other group called the denisovans, which have been discovered, genetically distinct moved into Asia and both eventually moved to Australia. Humans, homo sapiens came out much later, and effectively -- we can't say they killed them off, but within a few thousand years of when humans went into Europe, Asia, Australia, those other groups died off. That was complicated enough. Three species -- now new teeth have been found in a cave in China, and the interesting thing is, of course, I'm not --

Ted Simons: How do you look at teeth like that and say that is a new species?

Lawrence Krauss: That's the big question. You can compare them to any teeth you have seen and say they are not like them. Open question, I think, is that enough to say they're a new species? There is a lot of disagreement on that, there’s a lot of questioning. I think I said on the program before, if I went to see, a basketball game and some reason the roof collapsed and killed me and basketball players. 500,000 years later, if you looked at basketball players and -- two different species were existing at the same time. It is very difficult to know what we mean by species. We are just beginning to understand whether these things are variants of the same group or really different species. What we have been able get -- we just had an event at ASU with a wonderful scientist from the institute in Germany, the first person to sequence DNA from Neanderthals and we now sequenced DNA from -- genetically we can begin to look and that is much more efficient than looking at skeletons.

Ted Simons: Not homo erectus, not Neanderthal -- could these -- the child, the love child of these --

Lawrence Krauss: There has been interbreeding as far as we can tell between all of them which by the way means the definition of species created when I was a student and when you were a student, which is a long time ago for both of us, species couldn't breed and produce offspring viably. That is clearly not a good definition. There is -- from looking at their DNA, we know there was a lot of interbreeding. In fact, we just had an event that I'm happy to say my university president, Michael Crow is about 3% Neanderthal --

Ted Simons: Really.

Lawrence Krauss: You can go to a company called 23 and me and get your DNA sequence and find out what percentage of Neanderthal you are. Between two and five percent of our genetic make-up right now is Neanderthal. To put it dramatically, if you ask how related are we to Neanderthals. It is like as if you go back six generations. One of your ancestors was a Neanderthal, that’s how closely we are related to Neanderthals. There was interbreeding and clearly - The question is, you form new species when they're isolated. Asia was really big. Species began to look different, but is it enough to call it a species? There is superficial differences right now between many different groups on earth in characteristics, but they’re all species of homo sapiens, so I really think it’s premature to say there’s a new species but what’s clear is there could have been and there could have been a lot of different dominant species -- one of the big questions which is open, is why did we survive? Why not them? Would the word be a better place if it was full of Neanderthals, were they kinder or gentler? What was it about humans that they were efficient killers, if you want. All of these questions are interesting questions.

Ted Simons: Last point on this. Fossils found in China, Taiwan. A jaw found in Taiwan that didn't match as well. Why don't we see more of these fossils? Are they out there we just haven't found them?

Lawrence Krauss: Of course, it's hard to find. They're probably out there. You know, limited in money to be able to look for it. But, you know, you have to look for places which are well preserved that have not been subject to any kind of disruption in the interim and I suspect there is a lot more out there. In some ways it is kind of amazing that there is any anyway. Isn't it amazing that someone falls and gets eaten by a saber tooth Tiger or whatever happened, but because of circumstances their skeleton survives in one way or another in the right conditions. In some ways it is amazing that we can finds -- these are just a few hundred thousand years old. We found human bones, and my colleague found -- 3.2 million years old. So, they're sporadic but filling in. What is really neat, this is just the beginning. Fossil record will get a lot more complete and some of what we think now will turn out not to be true. Except what is clear there were three different genetically different groups that I can honestly say that.

Ted Simons: And real quickly, one last point on this, I talk about how come you can't find more? We think of humans everywhere, billions of humans everywhere. There weren't a whole heck of a lot of Neanderthals --

Lawrence Krauss: All of the evidence genetically, human, population at one point was reduced to the southern tip of Africa – where they originated to maybe a few hundred people. So, imagine if they had died out, which they were on of the edge of extinction, if they had died out, none of us would be here, and we are all related to those 100 people or less. And it is kind of amazing that right now, of course, there are more people existing on the planet now essentially than have existed in all of human history up to that point. The population of the earth is ridiculously high. That is one of the big problems. There is a lot we're learning from sequencing Neanderthals. I just learned, for example, some of the Genes for diabetes we got from Neanderthals.

Ted Simons: Really?
Lawrence Krauss: You wonder why because it wouldn’t seem like a positive thing that you’d want to get in evolution -- it turns out it was probably better related to being able to handle starvation. That Gene is not good when you eat a lot. If you are starving, it may allow you to adapt better. Early days, humans and Neanderthals were probably starving a lot.

Ted Simons: Something else I want to get to this solar dynamics observatory. First of all, what -- before we look at the video, what is it the NASA solar dynamics --

Lawrence Krauss: It is an observatory sent up as a satellite a little over five years ago to observe the sun in many different frequencies and measure magnetic properties of the solar surface – to basically look at the fact that the sun, here on earth, likes like a round sphere pretty much the same every day. It is incredibly dynamic. You have got to remember that inside the sun there’s about an equivalent about 100 billion hydrogen bombs going off every second. That’s pretty dynamic.

Ted Simons: With that in mind, let's go to the video.

Lawrence Krauss: Amazing video.

Ted Simons: Let’s roll the tape because this is --

Lawrence Krauss: Look at this all day.

Ted Simons: And this is stuff that -- that is Venus.

Lawrence Krauss: Transit of Venus. It is on twice here.

Ted Simons: Unbelievable.

Lawrence Krauss: Look at that. These are shooting up. The earth is about one-1000th the diameter of the sun. So the earth is much smaller than any of these huge solar flares we're seeing and magnetic fields -- each one of them generating up these storms is much, much bigger -- look at this. This is just amazing.

Ted Simons: That's outrageous.

Lawrence Krauss: These are not small flames. They are going out millions of miles from the solar surface.

Ted Simons: How often does something like that particular explosion happen?

Lawrence Krauss: We're just learning. Basically things like that going on at different levels of activity every day in the sun. One of the reasons to understand the dynamics of the sun is because what happens on the surface of the sun affects what happens on earth. Because there is things called coronal mass ejection, huge amount of energetic particles coming out, extreme ultraviolet radiation. Turns out our Ionosphere, which affects our weather. Ionosphere, upper part of the atmosphere that gets ionized by solar radiation -- it depends on how active the sun is. The sun, 11-year solar cycle. Sometimes they are much more active than others. If a really big one is emitted, then it can affect not only just the weather on, but potentially affect radio communications on earth. At the same time these beautiful images, which you should go online and see, they are just amazing to see the dynamics of them. Each of those sun spots which represents areas where magnetic fields on the surface of the sun are very different. Temperature of the sun 5,000 degrees at the edge, but the temperature in some of these regions of high filaments can go up to millions of degrees.

Ted Simons: What are we looking at there? That looks different than some of the flares.

Lawrence Krauss: A different wave length. Look at that. It is amazing. They are going out and coming back in. Why? The sun has a lot of gravity. Ejected at thousands of miles an hour but it comes back in and we want to understand what dynamics causes that cycle. What dynamics the sun is because not just intrinsically understand the evolution of the star, our nearest neighbor, but because as I say, life here on earth in many ways -- at the same time as this by the way, this week, satellite was launched, happy to say, by actually space-X, a private company -- there is Venus again. That will actually go out to about a million miles away from the earth to be able to measure that solar wind and magnetic fields and give us a 60 minute to two-hour warning, if any huge ejection is taking place so we can turn down sensitive devices.

Ted Simons: Something we saw there, that could knock out power grids, disrupt communications --

Lawrence Krauss: It could in principle depending on what kind of radiation is being emitted. That is why we want to understand the dynamics of the sun. But you can clearly see that the sun, the Large scales it is pretty stable, happily, more or less the same. It has been progressively hotter. It’s 15% hotter than it was 2 billion years ago/ And in 2 billion years, it will be 15% hotter still. You and I would exist on a planet about 1,000 degrees -- the fact that the sun is dynamical – it’s not surprising. If you think about it, 100 billion hydrogen bombs going off in the core every second means there is a lot of energy there. In some sense it is surprising that it is as quiet as it is because of all of that.

Ted Simons: What we saw was like five years of --

Lawrence Krauss: That was 1800 days of the sun. Celebration video that was put together, the mission of this satellite was a five-year mission like the USS enterprise of Star Trek. They put together a compilation of the incredible images that have taken place over the five years.

Ted Simons: Did we learn anything different as we look at the images – this particular dynamic observatory. Did it teach us anything?

Lawrence Krauss: I -- the answer is it is still -- data is still being processed. We have learned that this 11-year solar cycle exists, of course, we knew that, but we are seeing that the kinds of ejection material, energetics, ultra brown radiation varies in ways we are just learning about. I think it is a long ways before we will be able to explain it all. Data is necessary before we can develop theories that allow us to understand the dynamics of the sun.

Ted Simons: The other thing that launched is up there in place. The gravity of the sun and the earth keeping it in place?

Lawrence Krauss: Shot out to that wonderful point between the earth and sun, in the middle where the sun is pulling in one direction, earth pulling in another, it is just going to sit there. Wonderful stable point, and it will give us an advance warning. We see these things, we're not sure how much material makes it out. But these things will measure that solar winds, and the magnetic fields and the energetic particles and radiation and give us, you know, hour or two warning if sensitive devices need to be turned down.

Ted Simons: Hour or two to panic, sounds good to me.

Lawrence Krauss: No, no.

Ted Simons: We're going to panic, aren't we?

Lawrence Krauss: No, no, we are just going to hope for the best. It is not going to cause massive devastation. It’s just sensitive electronics -- satellites, particularly susceptible, more so than the earth, which a lot of radiation is protected by our atmosphere. U.S. government and defense departments care about that.

Ted Simons: Good to see you. Love that shirt by the way.

Lawrence Krauss: Thank you very much, me too. Your suit is nice, too.

Ted Simons: Wednesday on “Arizona Horizon”, we will hear from the president of the state Senate and Speaker of the House to get their impression of the current legislative session. House and Senate leadership on the next "Arizona Horizon." That is it for now. I’m Ted Simons. Thank you so much for joining us. You have a great evening.

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