SGU Episode 348: Difference between revisions

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E: Across the desert
E: Across the desert


J: This is a quote from him, he says
J: This is a quote from him, he says:
"We're trying to be very careful at this stage about definitely classifying them...One of the reasons for that is that in the science of human evolution or palaeoanthropology, we presently don't have a generally agreed, biological definition for our own species, believe it or not. And so this is a highly contentious area,"
<blockquote>"We're trying to be very careful at this stage about definitely classifying them... One of the reasons for that is that in the science of human evolution or palaeoanthropology, we presently don't have a generally agreed, biological definition for our own species, believe it or not. And so this is a highly contentious area," [http://www.bbc.co.uk/news/science-environment-17370170]</blockquote>
 
J: So, that's a little reassuring that one of the lead study members is basically casting doubt on any of the conclusions that they might be finding
J: So, that's a little reassuring that one of the lead study members is basically casting doubt on any of the conclusions that they might be finding



Revision as of 10:51, 16 April 2012

page in progress

Links

Skeptical Rogues

  • S: Steven Novella
  • B: Bob Novella
  • R: Rebecca Watson (absent)
  • J: Jay Novella
  • E: Evan Bernstein
  • RS: Richard Saunders

Introduction

You're listening to the Skeptics' Guide to the Universe, your escape to reality.

S: Hello and welcome to the Skeptics' Guide to the Universe, today is Thursday March 15th 2012 and this is your host, Steven Novella. Joining me this week are Bob Novella

B: Hey everybody

S: Jay Novella

J: Hey guys

S: Evan Bernstein

E: Hello everyone

S: and we have a special guest Rogue with us this evening all the way from Australia, Richard Saunders

RS: Hello Rogues, I hardly know what country I'm in, I've just flown back from the UK, in fact, only 2 days ago. So I'm still not sure about time zones and all that.

S: Yeah, you are definitely an international jet-setter.

(laughter)

E: an international skeptic of mystery.

B: do people still use that phrase? Jet-setter?

SR: As long as you guys use that phrase, that's OK.

S: It's coming back.

J: So what were you doing in the UK, you said?

SR: I was, I had a wonderful time as a guest of the people at QED: Question, Explore, Discover, the convention in Manchester that was on a couple of weeks ago, and what a great convention it was. It was sort of like being in a bizarro-world of being at a TAM, but being in the UK, which wasn't a TAM. But it was just that good, it was fantastic.

S: Yeah, I went last year, those guys did a great job.

B: I've been dying to go, I've gotta find the time to get out there. But, you know how it is, Richard, it's much harder for you, you've got to take a lot of time off, you can't just pop over. You've got to take days off to get there.

RS: I love travel, but I would travel twice as far as I have to go to something like QED in Manchester, they put on such a great convention. Good to catch up wit some old friends, like D.J Grothe and Joe Nickell, of course.

S: Well let's get started, we actually have a lot of news items to get through. Evan, you're going to start us off with This Day in Skepticism, covering for Rebecca, which I should mention, if you haven't figured it out by now, Rebecca is off this week. So Evan you're back in your old role.

This Day in Skepticism

(2:03)

E: ooh, I'm gonna get comfy. It still fits, this is good, this is good. I'm comfortable. Alright, March 17 1958 - the Vanguard 1 satellite was successfully launched into Earth orbit [1]. So, what was special about this particular satellite? It was the fourth artificial satellite launched into space, but the first to be solar-powered.

S: Really.

E: It is still up there.

S: Is it still working?

E: er, not still working. They kinda lost functional communication with it back in 1964.

S: So it's a hunk of metal orbiting the Earth now?

E: Yeah, it wasn't always that, it evolved into just a hunk of metal

S: It's space junk

J: It still operated longer than they thought, I mean, for a solar-panel Steve, come on

S: Yeah, that's good, it's great

E: They say it's going to stay in orbit well into the 22nd century. This thing was built to last. Except for the, you know...

S: Not necessarily to function, but to last

E: and part of the Vanguard project, which served lots of different functions, it's primary function was to obtain accurate measurements of the Earth through orbit analysis, and they determined it's precise shape, and sort of for the first time we knew it had these bulges

B: Lop-sided, oblate spheroid.

E: Exactly, so we learned some good stuff, and if you look at a picture of it, it certainly reminds you of Sputnik. You know, that sort of image, with the ball and the thin arms protruding from it. So, it has that sort of retro satellite sort of look and feel to it.

RS: A 'retro satellite look', isn't that a funny expression

(laughter)

E: Who ever thought we'd be able to say that?

S: Yeah, we're at a point where satellites can look retro

(laughter)

J: Like a 'retro laser pistol'

S: Well, laser pistols have always been retro

B: Right, and they don't even really exist

RS: When they finally invent them, do you think they'll look like phasers? like the old things on TV?

J: Yeah, I hope so.

B: Yeah, if you figure that the aesthetic doesn't really matter that much, if they have to put a little cool casing on it or whatever, they better damn well make it look like a phaser from Star Trek, or something from Star Wars, I mean, come on.

J: But a cool one, not a lame one

RS: Lost in Space rifles

J: Aw, those were bad

S: Alright, well thanks Evan


News Items

Oldest Skeleton

(4:32)

S: The first news item, this is just a quickie, but it's really neat.

B: Quickie? Quickie?

S: Not that kind of quickie. But, scientists have discovered the oldest skeleton on the earth [2]. You guys hear this?

B: Yeah, this is pretty cool, it's like a cordate, worm-like-

S: It's not a human skeleton, obviously, it's the oldest skeleton of any kind of creature, and this species is Coronacollina acula. This is a pre-cambrian animal from the Ediacaran era, so they date it to between 560 million and 550 million years ago. The Cambrian explosion occurred around 542 million years ago. This creature lived on the ocean floor, like attached to the floor. It looks like a little thimble with at least 4 long spicules coming out from it. They don't know what the purpose of those structures was, they could have been just to stabilize it on the ocean floor. And originally, do you know where this fossil was found?

RS: I certainly do! It was in my backyard, it was just extraordinary. No, it was found in South Australia, and you know what? It really does look sort of like Sputnik.

S: It does!

E: It does

S: A thimble Sputnik, instead of a ... grapefruit Sputnik. But, yeah, the 4 spicules look kinda like the antennae

RS: It does, it's very strange, but there is certainly a wealth of very, very old fossils in Australia, but this one is a bit of a surprise, this one's really old

S: Yeah, this is cool for a lot of reasons. So, a quick background, the Cambrian Explosion is when we first start to see multicellular animals in the fossil records, with hard parts. Now there are some fossils of Ediacaran fauna from before the Cambrian, but they are mainly soft-bodied, like flat type of creatures. And one question is, well what happened to the Ediacaran fauna? and where did the Cambrian fauna come from? One hypothesis was that Ediacaran fauna essentially dies out right before the Cambrian explosion. But the other possibility is that animals and plants, or whatever, creatures that are present in the Cambrian explosion were around, they existed in the pre-Cambrian, they just hadn't developed hard parts yet that fossilized, so we don't see them. So, the Cambrian explosion, in part, is an artifact of the fossil record. It may actually represent a dramatic, rapid increase in the number of animals in the world. But it's also that when animals start to develop hard parts they will suddenly appear in the fossil record, even if they had a much longer history.
Well this creature actually has some structures in common with Cambrian sponges, and that suggests that this creature is an ancestor to certain animals that existed in the Cambrian and therefore, not all the Ediacaran fauna went extinct, and Cambrian creatures' ancestors were around in the pre-Cambrian. So that sort of supports that there was a long lead-up to the Cambrian explosion, and it was partly, or mostly, an artifact of developing hard parts that the "explosion" occurred. So this is actually a really important fossil find in terms of our understanding of this period of time on the Earth and the evolution of life. And it is also, in a way, an important evolutionary prediction that there would have been antecedents to the Cambrian fauna, you know, these creatures would not have come out of nowhere, they had to have ancestors, and now we've found one. It also makes sense that we would find the first creature to develop hard parts. Maybe there are others out there that are waiting to be discovered, and you're right, Richard, Australia is a very rich location for this period of time. The oldest living things that we're finding on the Earth are being discovered in Australia.

RS: Yes, and I'm one of them

E: Not quite there yet.

RS: But it's interesting, the way you put this, as the explosion where it may have been an explosion before, but we don't know about it. But I guess you could still classify it, if these skeletons came along, then it's an "explosion" of this form of life, the ones that adapted skeletons, something which could fossilize. So I guess it's an explosion no matter how you look at it.

S: Yeah. Of course, the creationists try to present it as a 'sudden creation', but that's not what we're talking about at all. And sudden meaning over several millions of years.

RS: Yes, we've got to be careful about the way we express ourselves here, it's sudden but it's like in slow motion of course. I guess it's just the way we're used to using the word when we' speak about the fossil record.

S: It's geologically sudden, but it's still a long period of time.

Red Deer Cave People

(10:05)

S: Let's move on, Jay, we have another sort of archeology, or paleontology, related item. Paleontologists have, in other skeleton news, discovered perhaps a new species of human living not that long ago.[3]

J: In other skeleton news, I like that.

(laughter)

J: A team of scientists have been studying bones of five or maybe more individuals that date between 11,500 and 14,500 years ago, and this collection of bones have been named after one of the sites where the bones were found and that's why they are called...what are these people called?

S: Red Deer cave people.

J: Right, cos one of the sites was called Red Deer cave, but it wasn't the sole site, there were actually several sites that they were finding the bones. So the bulk of the skeletal remains have been in a Chinese collection, or one or more Chinese collections, but recently the collection has been under extensive investigation, and they're finding a lot of really, really interesting things about this. Skulls and teeth from 2 locations are very similar, and this most likely means that they're from the same population, and they also found that they have a mix of archaic and modern characteristics, the features are considered distinct from modern humans. And some of the descriptors that they gave were thick skull bones, short and flat faces, broad noses, rounded brain cases, prominent brow ridges, and the jaws also jut forward, but lack a modern human-like chin. They had modern frontal lobes, but quite archaic-looking anterior or parietal lobes. Steve, what does that actually mean?

S: Well, those are the lobes of the brain. So you have the frontal lobes which are at the front, temporal, which is like by you temple, the parietal lobe would be behind that, and then the occipital lobe in the very back.

J: Cool, so those parts of their brains weren't as developed as much as a modern human

B: Right, so they're just going from the shape of the skull to infer the size of the various parts of the brain

S: Sure, that's a pretty good indication.

B: One thing that struck me about this when I was reading about it was it said the skeletons and the skulls were like a mish-mash of archaic and modern features, and the first thing I thought of was like, oh boy, Piltdown man, how do they know that this isn't a hoax, and what steps have they taken to make sure that this is a legitimate thing. And I was just wondering if it struck you guys the way it struck me when I read about it. And it's weird, cos even the fact that it was found in China made me think, well, are they just trying to get some notoriety and are they making this stuff up?

J: Well, I'll tell you why I think it seems more legitimate. First of all, they're not making any claims of anything definite, they're saying a lot of maybes and I'm going to talk about that a little bit later, cos I've got a lot more information to give you guys. They had a few ideas about the origin and all that, but they're very openly saying that they need to do a lot more investigation, they're actually trying to do DNA testing to get some more information about them, and plus, Bob, this isn't just some random skull.

S: There are five individuals, Bob, and for me that's the biggest hedge against this not being a hoax I agree, you know, China has a history of fossil fraud, of selling fake fossils to make money. So you've always got to be curious, but it looks like they're coming under scrutiny, and we obviously have to wait for these to be really evaluated by the scientific community. But it sounds like they're starting to be evaluated, and I think with multiple individuals- I think that this fits quite well with what we've been discovering over the last ten years or so, that Neanderthals, and Homo sapiens and other sub-species were...

E: They were gettin it on

(laughter)

S: There were lots of sub-populations, with different features, so seeing one sub-population living in that area that had some persistent, you know, Neanderthal mixture of older and more modern features makes perfect sense compared to what we've been seeing.

J: Hey, Bob, I have a quote here, one of the study co-leaders, Darren Curnoe from the University of New South Wales, Australia - hey Richard, do you know this guy?

RS: Oh sure, he just lives down the street

(laughter)

RS: No, I don't

E: Across the desert

J: This is a quote from him, he says:

"We're trying to be very careful at this stage about definitely classifying them... One of the reasons for that is that in the science of human evolution or palaeoanthropology, we presently don't have a generally agreed, biological definition for our own species, believe it or not. And so this is a highly contentious area," [4]

J: So, that's a little reassuring that one of the lead study members is basically casting doubt on any of the conclusions that they might be finding

RS: It seems to me that they're taking a very reasonable approach to this, just being very cautious about it. But when I see those dates, I'm just amazed to think that there were other species of humans running around only 11,000-odd years ago, it's insane.

J: Yes, it's very weird

B: That's nothing

E: So you think about the mammoth also that was running around about the same time, and that's hard to grasp

B: For mammoths, you're going back 4, 5, 6,000 years ago, even more recent

RS: We missed it by that much

(laughter)

J: So, Steve, I wanted to hear about a few of the theories that they're throwing around. So, they've discussed, Dr Curnoe and his team have two scenarios, and other scientists that were following the research have a third scenario, and I'm curious to hear what you guys have to say. So, the team have speculated that the findings might mark a very early migration of a very primitive homo sapien that lived separately from other forms in Asia before dying out. And the second idea they had was that they were indeed a distinct homo species that evolved in Asia, and lived alongside our own kind until remarkably recently. Then other scientists, as I said, have said that these are just hybrids.

S: Those are the theories, they're just saying all the possible ways to fit that data, I think that's it. I don't think that at this point they have any particular reason to think of any one or the other. They could be hybrids, they could just be, as you said, a sub-population lingering in this region. I think we're gonna be seeing more and more of that as we discover more and more human fossils throughout Europe and Asia. Remember, there was that other population found in Siberia, remember 'homo floresiensis', the 'hobbit' on the island of Flores. Evolution is a messy, branching bush, and we're just finding more and more twigs all over the place. Alright, thanks Jay.