Blue Collar Scientist

The second issue of Evolution: Education and Outreach is available on the Springer site.

The irritating and user-hostile necessity of downloading every article separately as a PDF has not been resolved for the new issue. But it is still well worth reading it if you are teaching this subject.

Evolution education in this country (the United States) is in some serious trouble. As is well known, we have a large population of people whom the schools have failed, who believe that the theory of evolution makes claims that it does not. In place of the reality of evolution, they have chosen to believe the creation myth of a bronze-age middle eastern religion, which was largely plagiarized from four earlier Mesopotamian myths. The worldview of this “alternative” asserts that knowledge is essentially undiscoverable and unchangeable, that observations of the universe must conform to limits that are pre-defined by these myths, and that people who do not agree with the repressive system of “morality” that accompanies these mythic beliefs are unfit to exist in society.

Accordingly, it is very nice to find a free periodical resource designed to aid those doing education and outreach on the topic of evolution. Springer has a journal called Evolution: Education and Outreach, designed to help instructors of K-16 with their activities. And they have decided that during 2008, anyone may receive the journal free online. This is stale news; somehow I missed it when it was launched last November.

Free access is good, very good indeed! And Springer should be commended for this.

On the other hand, they’ve made it painfully difficult to get a copy of the journal online. As far as I can tell, it is actually impossible to get a copy of the journal online.

What you can do instead is get a separate copy of each article in the journal, requiring at least 21 separate downloads for a single issue of the journal.

To do this, go to the very counterintuitive page that apparently lists issues of the journal. As I write, there is only one issue of the journal available. But don’t be confused by the link to “Online First,” because that’s not it. What we’re looking for is Number 1 / January, 2008 - click on that instead.

Once you have done that, you’ll be on a page that lists the articles in this issue of the journal. At the top of each section are the article titles. Other than the title, there’s no way to determine what the article is about. If you click the title, you don’t get the article - you get an abstract (sometimes), and you get some information about who, if anyone, has cited back to that article. Clicking the title is about as expensive in terms of effort and download time as just downloading the article and skimming the first couple paragraphs to learn if it is topically relevant with what you are doing. So there’s no real point to clicking on the title.

To get the article, you need to look a few lines below the title, to the “Text:” field, and click on either PDF or HTML, depending on which format you want to read the article in. I’ve now read a few articles in each format. Strangely, PDFs download a lot faster than HTML (sometimes HTML articles simply won’t load at all). And if you click on the HTML link, you may wonder why nothing happens, depending on what browser you are using and how it is configured - the HTML link insists on opening a new tab or window without telling you, and this can be puzzling if the new page opens hidden behind another one.

Anyway, if you do all this properly, you can read the whole journal only after an absolute minimum of 24 clicks (and 21 save-as dialogs if you are saving PDFs locally to read offline). Everywhere else on the web, one click would do to read a PDF version of a journal. And don’t fool around with the “save this item” or “download this list” icons, because they don’t do what normal web users think.

This system sucks, and it will obviously discourage people from reading. I know Springer is a journal publisher, and I know publishing journals in this way makes sense when your readers are highly focused on specific topics. But they’re publishing an EPO aid in this case, not a research journal, and most of its audience is not going to be savvy to Springer’s proprietary online journal publishing system. Nor will they find its bells and whistles useful.

The contributors to and publishers of this journal need to take a look at what we’re up against: a horde of ignorant evangelists who enjoy single-click downloading of articles at their primary “research” sites such as Answers in Genesis.

The resource content is actually pretty good. I recommend going and reading it if you are doing science EPO that ever touches on evolution, as I am.

Springer: Single-click download, please. Until then, you get a D-.

Andrew Kitchen, Michael M. Miyamoto, and Connie J. Mulligan report in PLoS-ONE on their development of a three-stage model for the colonization of the Americas by Homo sapiens. This issue is of deep interest to anthropology outreach in Alaska, and I’m accordingly very interested in the paper. The attention that these ideas will likely receive in Alaska suggests several major avenues for effective public outreach:

• It provides an opportunity for “what is the nature of science and knowledge” education. The concepts of falsifiability and refinement of knowledge over time are particularly rich opportunities with these new results.
• It provides an opportunity to provide some “cutting edge” science to students. As noted below, many of the interpretive materials in greater Anchorage on these subjects reflect what was “cutting edge” twenty years ago, but which is now largely rejected in paleoanthropology.
• This paper is largely about analysis of genetic populations, and statistics. Therefore, it is an open door to talk about mutation rates and evolution, and some simple statistical exercises could easily be devised to give students an idea of what the authors are doing in their analysis.
• It provides an example of multidisciplinary work in science. The authors present a genetics analysis but subject it to controls imposed from other fields.
• Because some broadly similar studies of the past have not been subject to those controls, it provides an example of why there might be apparent disagreement about knowledge amongst scientists. For example, I’ve heard about genetic data that supports migration into the Americas both much earlier, and significantly later, than well-dated archaeological sites. By not imposing constraints from other fields of study, such findings result in apparent disagreement, without necessarily being valid disagreement. The distinction is worth teaching since organized antiscience uses such cases as a wedge.

The authors propose that the population of Amerind ancestors expanded out of east central Asia between 43,000 and 36,000 years ago, and occupied Beringia, the easternmost portion of Asia and the western part of Alaska, including the sea floor which was exposed at the time. A stable population of 8,000 to 10,000 people remained there from that time until around 16,000 years ago, at which time 1,000 to 5,400 of them rapidly expanded into the Americas. The study conforms to prior hypotheses that this expansion occurred either through an ice-free corridor in eastern Alaska and western Canada, or along the coast.

Consistent with other recent work, this paper proposes a single migration, as opposed to studies of the past that considered Amerinds, Na-Dene, and Eskimo-Aleuts to be the result of different migrations. This hypothesis gained popularity in the mid-1980’s, and is the model adopted by a number of interpretive materials in and around Anchorage. The model has been in disfavor for some time in the professional literature, and it seems likely that this new study would help to change these interpretive aids (assuming that scientific evidence trumps political expediency).

The authors point out that the genetic studies to date have strongly supported a single-migration model, but that they have varied significantly concerning the proposed date of the migration, with dates anywhere from about 13,000 years ago, to 40,000 years ago. As a result, that data has been interpreted by a variety of scenarios involving additional migrations, migrations of various ages, and so on. At least from the layman’s perspective, many of these seemed like clever possibilities that had the unfortunate air of being ad-hoc about them.

The new study accommodates some of the more puzzling aspects of the prior genetic studies, particularly ones that come up with very old dates of 30,000 years or more for the migration. A stable population in Beringia for some thousands of years would explain those results, and also explain why there are no American archaeological sites older than around 15,500 years old, while accommodating nicely the archaeological evidence that Homo sapiens was in northwest Beringia by about 30,000 years ago.

The study incorporates data from both nuclear and mitochondrial DNA of both Native Americans and Asians. Mitochondrial DNA evidence was cited in 2005 (with quite a bit of publicity, at least in Alaska) to support the idea that the population colonizing North America was extremely small, so it appears to me that the re-analysis of the mitochondrial data is of particular interest. Also of interest is that this study, unlike some in the discipline, uses archaeology, geology, and paleoecology as opportunities for imposing controls on the analysis of the genetic data. Some of the genetics studies of the past have given the appearance of being statistical analyses that avoided giving very much consideration to what is known from other disciplines. The study constrains divergence time to 15,000 years ago, and by trying out different migration rates between Asia and Beringia (and back), it is shown that the lower (and “more biologically realistic,” as the authors put it) the migration rate the larger the population of Amerind ancestors:

Our results demonstrate that smaller estimates of Ne depend upon a substantial level of migration from Asia to account for present-day levels of Amerind genetic diversity, e.g. Hey’s estimate of ≈70 founders is associated with a mAsia→NW > 9.0, which is twice the migration rate for contemporary Europe (m = 4.3).

Emphasis mine. I agree with the authors that the high migration rates assumed by other studies are implausible. Intuitively, I have a hard time accepting that the rate of migration on a modern industrial continent serviced by jets and trains is substantially lower than that found in east Asia in the Pleistocene, but I’m not an expert.

The authors also build into the paper a very nice opportunity for those doing outreach to talk about “what is science:”

Our goal is to provide a comprehensive model for the initial settlement of the Americas that generates new testable hypotheses and has high predictive power for the inclusion of new datasets. In light of our results, we propose a three-stage model in which a recent, rapid expansion into the Americas was preceded by a long period of population stability in greater Beringia by the Paleoindian population after divergence and expansion from their ancestral Asian population.

In other words, science produces conclusions that are testable. When you come to a conclusion, you are sticking your neck out a bit - because by definition a scientific finding is subject to being disproved at some point by someone who has better data, or is better at interpreting your data than you are.

One of the most interesting aspects of this paper, from an outreach perspective, is the opportunity to discuss how we know the dates. Here in a single paper are incorporated various methods for dating prehistoric events and materials (carbon dating, stratigraphy, genetic statistics, and surely a few others), and all of the methods agree that this recent event in world geological history still took place thousands of years before some believe the world was even created. The contrivances that are required to refute these vastly different, yet mutually-supporting dating techniques are awesome in their implausibility, and that’s where the teaching opportunity comes from.

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This blog article is about:

Kitchen, A., Miyamoto, M.M., Mulligan, C.J., Harpending, H. (2008). A Three-Stage Colonization Model for the Peopling of the Americas. PLoS ONE, 3(2), e1596. DOI: 10.1371/journal.pone.0001596

The BBC, LiveScience, and others are reporting on the discovery of a new pterosaur found in north-east China. The find also confirms a prediction of evolution. From the BBC story:

“It is very likely that this pterosaur represents a lineage of arboreal creatures that lived and foraged for insects in the gymnosperm forest canopy of north-east China during the Early Cretaceous,” the researchers write in PNAS.

They conclude this from curved bones in the feet, which are similar to those found in perching birds. This pterosaur is also smaller than most others, of a size that makes sense for perching on branches. Cladistics suggest that this pterosaur was close to the ancestors of the giant pterosaurs, including Quetzalcoatlus, which had a 30-foot wingspan. Thus the new fossil is transitional, being in some ways less derived than later specimens but more derived than the pterosaur’s hypothesized concestor.

“It is interesting to see some clear arboreal adaptations in this species,” said [Smithsonian paleontologist Matthew] Carrano, who was not on the research team.

“It confirms a suspicion we had, that pterosaurs were more diverse in their habitats than we knew from the [fossil] record.”

Let’s be a bit more direct here, in the interests of effective science outreach and clear communication. The notion that pterosaurs were more diverse (in their habitats, or in their phenotype - both apply) than the fossil record previously demonstrated is a prediction of evolutionary theory, not merely a suspicion of paleontologists. There are actually two predictions here, both of which are confirmed by this fossil.

1. Evolution predicts that some species will be absent from the (known) fossil record, and that some of them, if they were known, would illuminate the evolutionary development of their lineage. Here we have an example of a fossil which was unknown until recently, and which does just this. Score one for evolution.
2. Evolution makes the more specific prediction that, when you have lots of fossils of lots of species with specialized adaptations - such as pterosaur fossils - that less derived species will exist earlier in the lineage. Not only that, but it says that most of the characteristics that are common to most or all of the more specialized species will be present in the less derived one. Again, from what’s been published, this fossil confirms this prediction.

Seems I’m on a paleontology kick lately. Undoubtedly this is a result of spending so much time in museums over the last month, looking at fossils. Fair warning - there’s at least one more of these in the pipeline. I’ve had some interesting information and photos from the PI of the crayfish fossils I reported on earlier that I’m working up.