Introduction

Where did we lose the vast majority of people? I don't think it's just hormones after you get done with them. I think it is the media, especially television. Television is really rotten when it comes to science and it's getting worse. I say this to my scientific colleagues and every once in awhile they'll say to me, "Oh, no it's really good, Jere. I watch PBS." Oh, sure, but only about three percent of the population watches PBS. You're talking to the converted already. Let's get to those other people who understand very little about science, and let's get them through NBC, ABC, CBS and that absolute pseudo-scientific network Fox.

Oh, I've got to tell you about the Learning Channel. How many of you watch the Learning Channel? How many of you caught "Alien Abduction Week" last March on the Learning Channel? Did you see "The Mysterious Origins of Man" in October on the Learning Channel? They bought it after NBC showed it to a few tens of millions of people. It dealt with paleontology, my field, and I can tell you it was pure pseudoscience and antiscience. That's the un-Learning Channel, actually. Don't let your kids watch that. I don't.

So let's talk then for a moment about a couple of other media. You know Time Magazine. I hold up my copy because I asked Time Magazine if I could use pictures of their covers. They said, sure for $200 a snapshot. So I'm holding it up. I bought this one with my own money so I can show it to you. This cover shows "Evolution's Big Bang", and I want to tell you about that today because I want you to use this, if you can, as an exciting thing in paleontology, and look at some of the pictures in here and at what I'm going to show you today--pictures of the field, pictures of scientists, and I'll tell you this: these paleontologists are every bit as weird and fun and exciting as anybody on those situation comedies or dramas on NBC. You see us up here in suits now, and usually I do throw on a tie for these things, but I wanted to come across a little more like an outraged person. Am I doing OK so far?

But how many people--and you know, I'm really proud that Time magazine has covers on evolution's big bang and the origin of life. There was one on dinosaur extinctions that actually had two dinosaurs on the cover; one was T. rex and up in the corner was Ronald Reagan. Does anybody know the circulation of this magazine? How many? I think it's four or five million. It's not very many, really. I talked to editors of scientific magazines like Discover magazine and they say, "Oh, we're doing a great job." You sure are, your circulation is 1.2 million. Earth magazine--how many of you get Earth magazine? That's almost the total circulation. I exaggerate a little bit. It's 100,000. So, a lot of this exciting science and the scientists themselves are going unnoticed and unknown to the general public. This museum has about a million visitors on a good year. Most of those people are converted. The people that read this kind of stuff are converted already. They find it interesting. But even, I point out, on Time magazine's cover the subtitle is "New discoveries that show life as we know it began in an amazing biological frenzy that changed the planet almost overnight". I think that misleads a lot.

I should point out that Time magazine, although they've done these three covers I mentioned to you in the last two decades, they've done a cover on the Roswell Incident with a big alien on the front, they did one on angels, they did one on all kinds of superstitions and paranormal and anti-science stuff. They're no better, in some regards, than television. We've got to change this.

You guys, I think, are doing a great job. You're under paid but you're doing a great job. But you ought to get out there and fight to get this kind of good science, the exciting science and the exciting people that have interesting lives into the media and your class materials. I know a little bit about Stan's life. I won't say anything about it! I don't know anything about Richard's. But I bet you could build some good TV programs around them. I don't want them to touch my life, though!

Fossil Record

I'd like to point out a few of these things as we look at these rocks in more detail around the world. We're going to start down in the lower part to set the stage for what happens at this point in time. That point in time is about 545 million years ago, when we see the first appearance of abundant, skeletonized--in other words, with shells--animal life. I think this is exciting. Here's a close-up of that boundary. That's my backpack and my father's rock pick. That's the boundary. Down here Darwin and geologists at the time, paleontologists, did not see much. There was some speculation. Up above here they saw many fossils. So what was going on?

In order to understand that, I think we need to go back just a little bit. Here's an RNA phylogeny of life, very simplified, and you've seen this many times. I want to point out a couple of things. We're talking, when we talk about animals, about a little tiny twig out here on this end of the Eucaryote lineage, 545 millions years ago--actually probably a little bit more than that; we'll talk about that later on. That branch popped up there. There are about 26 other major groups that, if animals are considered to be a Kingdom, then they would have to be Kingdoms too, in the old terminology. And we have these two groups of prokaryotes, the Eubacteria and Archaebacteria. Some Eubacteria formed various organelles in the multicellular organisms that became incorporated in the Eukaryotes through symbiosis.

Now, Stan was talking about organisms over here and I want to go back and pick up where Stan left off with those and why they evolved, as Stan was saying. Some time, probably around 4 billion years ago, we see these bacteria that he showed us. I'll show you a few more pictures of those at about 3.5. The important point to realize here is that all the way around here, until about 1.4 or 1.5, we see the first true fossils that might be Eukaryotes. There's some evidence at 1.6 or around there that there were Eukaryotes existing, chemical evidence. And you've got to remember, every point here, when I say 2.5, each of those points is 100 million years. So when you go from 2.0 to 1.4, that's 600 million years. That's as much time as there has been from now back to the time period we'll be talking about mostly here.

I say this because I was at a teacher's presentation once and somebody was talking about the origin of oxygen at 2 billion years ago, and he said there was evidence for it at 1.8 and no evidence for it at 2.2 and therefore he said it was probably about 2.0 billion years. And somebody raised their hand and said, "Gee, how come it happened so fast?". Well, ma'am, that's 400 million years. That goes back twice as long as the dinosaurs have been around. That's plenty of time, as Stan was saying, for most stuff to happen.

So, what I want to talk about then is what happened in this period of time up to about here and then look at the period of time where we have the radiation, not only of animals, but of some other groups that we'll talk about in a moment. The important point, again, is that Eubacteria in the fossil record dominated for 7/8th of the history of life on Earth and they still dominate. We live in a bacterial world. Do not get excited about dinosaurs! It is bacteria that is important! I don't even work on the darned things, but Stan, now you owe me lunch! Here's one of these stromatolites, like Stan was talking about, from Western Australia at 3.5 billion years and from this kind of domal structure, they have found these kinds of fossils. And Stan has shown you some of those previously. They are inferred, as he did, to be cyanobacteria, fairly advanced kinds of things. We see these kinds of stromatolites throughout the geological record but mostly in Precambrian rocks. There are some in other rocks and we still have them around today, for example at Shark Bay. These domal structures, as Stan pointed out, were built, at least in the Precambrian, totally by these bacteria, cyanobacteria, which were cementing and trapping sediment on top of them to make these domal structures like mushrooms, giant mushrooms.

He also pointed out that there are bacterial mats that lay flat, and I've dove all around the world and seen them. Bacterial mats are really far more abundant than what we think. These kinds of stromatolites became less important after the arise of animals, presumably because the animals were grazing on these kinds of bacteria that make the mats. Well, if we go back to the Grand Canyon and we look at this large or very thick sequence of rock which is known here as the Chuar Group, there are lots of different kinds of fossils, as it turns out. Darwin just didn't have enough information. Not only are there stromatolites like the things that we just talked about but there are other things. So we made an expedition to fly into the Grand Canyon and collect just in that group of rocks that are around 800 million years old.

Here's a view of some of the sedimentary rock, very well preserved, very well bedded. And it's from those kinds of rocks, and rocks elsewhere in the world, we find some perhaps algae of some kind, fairly large, you can see the scale down here. And we see in rocks like these with some of the paleontologists over there collecting fossils, organisms like these which are probably some kind of an alga, an eukaryotic alga. These are still under study by various people around the world. That pretty much completes what we have in the biological record--I've left out a few things--up to about 600 million years, or a little bit less than that, when we see the first animal fossils.