evolution
evolvingthoughts | February 20, 2008
In a recent paper on biological nomenclature in Zoologica Scripta, Michel Laurin makes the following comment about the stability of Linnean ranks:
However, taxa of the rank of family, genus or species are not more stable. ...
This sad situation should not surprise us because the ranks, on which the traditional (RN) codes are based, are purely artificial. As Ereshefsky (2002: 309) stated, ‘they are ontologically empty designations’. Ranks were initially thought to be objective because, for Linnaeus, each rank reflected the plan of the Creator and could be recognized on the basis of…
evolvingthoughts | February 20, 2008
From The Blackwell Companions to Philosophy series comes A Companion to the Philosophy of History and Historiography edited by Aviezer Tucker. It looks fascinating, especially essay 36 on Darwin...
gregladen | February 20, 2008Everyone knows about Darwin's Finches, of the Galapagos Islands. But of course, Darwin made observations of birds throughout his travels on The Beagle. Here, I present a number of passages from The Voyage that include some of these observations.
Struthio Rhea
I will now give an account of ... the Struthio Rhea, or South American ostrich. This bird is well known to abound over the plains of Northern Patagonia, and the united provinces of La Plata. It has not crossed the Cordillera; but I have seen it within the first range of mountains on the Uspallata plain.... The ordinary habits of the…
pharyngula | February 20, 2008Take a look at this excellent list of evolution misconceptions. The entries are very brief, but mostly correct and very common: in particular, #12, "Natural selection involves organisms 'trying' to adapt" is one of the most common mistakes in creationist thinking — they completely miss one of the most important insights that Darwin had.
But I have to nitpick a little bit. #6, "The theory is flawed," gives the wrong answer — it basically tries to argue that the theory of evolution is not flawed. Of course it is! If it were perfect and complete we'd be done with it, and it wouldn't be a…
gregladen | February 20, 2008A good trick in child psychology is to come to a "compromise" in which the child, not knowing any better, gets what they think they wanted but it really turns out to be cod liver oil after all. Florida creationists got their cod liver oil when the Florida School Board voted, with a worrisome 4-3 count, to accept the proposed science standards that actually use the word "evolution."
The word "evolution," however, is qualified as a "scientific theory." That's the compromise part. Creationists, like young children, can get certain concepts very wrong, and this is one of them. We often hear…
laelaps | February 20, 2008Last November news broke of at least one Florida school district opposing new education standards that would bring the term "evolution" to the state's students for the very first time. Since that time opponents to the view have attempted to rally but never quite got their act together, and now it has been decided that the phrase "scientific theory of evolution" will be used in Florida public school science standards. This is a compromise (I'm sure we'll still be hearing "It's only a theory!" often), but in a general sense it's a win for better science education.
Some have hinted that the…
esiegel | February 19, 2008What? Is this a joke, Ethan? Have you been watching Jurassic Park again, drinking Dino DNA or something? No, I got an interesting question from startswithabang.com reader and ichthyophobe Lucas:
Over the years a few intact, frozen woolly mammoth have been found and procured by different scientists and governments, most recently Japan. What are they doing with these ancient popsicles? Cloning? Could a frozen woolly mammoth be effectively cloned?
Aaah, the woolly mammoth, something we think of as ancient, but really it only went extinct an estimated 3,700 years ago, with the last mammoths dying…
tfk | February 19, 2008Florida Citizens for Science is liveblogging the Florida Board of Education meeting on science standards.
clock | February 19, 2008I tried to understand what DNA barcoding is, as everyone is talking about it. And I tried reading a couple of papers about it - I am a biologist, so I should have understood them, but nope, I was still in the dark.
So, what does one do? Waits for a science blogger to explain it. And so it happens, Karen explained it yesterday. I read it. Slowly and carefully. Only once. And I grokked it all!
laelaps | February 19, 2008This morning I was browsing YouTube in an attempt to find some nutty creationist argument no one had seen yet, but instead I came across a few cable TV "debates" between creationists and defenders of evolution. They were painful to watch; the creationists proffered the same nonsense and the various skeptics/scientists often talked right past them and did not do a very good job at refuting the "freedom of inquiry" spin creationists love to use. This clip is a case in point;
Ouch. I don't have warm feelings for Anderson Cooper, either, as asking vague, "objective" questions that create such…
gregladen | February 19, 2008
Fallback foods are the foods that an organism eats when it can't find the good stuff. It has been suggested that adaptive changes in fallback food strategies can leave a more distinct mark on the morphology of an organism, including in the fossil record, than changes in preferred food strategies. This assertion is based on work done by the Grants and others with Galapagos Island finches, by Richard Wrangham and me with hominids, and by Betsy Burr and me with rodents.
The reason for this is simple. There is a rough correspondence between how much energy one can obtain from a food type and…
gregladen | February 19, 2008Comparing living chimpanzees to living humans, in reference to the species that gave rise to these two closely related species, is one way to frame questions about the evolution of each species.
Generally, it is useful to address evolutionary questions by comparing two living species with the reconstructed "last common ancestor" (LCA) of those species. All of the similarities and differences between the LCA and the living form, in each lineage, represent evolutionary "stories" (that could even be worked out as hypotheses). Similarities indicate important, long-maintained adaptations, and…
evolvingthoughts | February 18, 2008
A new paper, unfortunately not yet available to nonsubscribers on PNAS's Early Edition, has done some remarkable work on the evolution of canoe designs, putting some meat onto cultural evolutionary models.
The paper is nicely reviewed by K. Kris Hirst here, however. And when we mere mortals can get it, the paper is listed at the bottom of that and this post.
What Rogers and Ehrlich (yes, that Paul Ehrlich) did was analyse 95 variables in the design of the canoes of the "Lapita Complex", a group of Polynesians regarded as having colonised their islands around 1400-900 BCE. They found that…
gregladen | February 18, 2008Charles Darwin wrote a book called Geological Observations on South America. Since Fitzroy needed to carry out intensive and extensive coastal mapping in South America, and Darwin was, at heart, a geologist more than anything else (at least during the Beagle's voyage), this meant that Darwin would become the world's expert on South American geology. Much of The Voyage is about his expeditions and observations. Part of this, of course, was figuring out the paleontology of the region.
Bahia Blanca is a port at the northern end of Patagonia. Chapter V of The Voyage begins:
THE Beagle…
evolvingthoughts | February 18, 2008
Back when Darwin was a student at Cambridge, he read, and almost memorised the Rev William Paley's Natural Theology, and thereafter remained impressed by the obvious adaptiveness of the parts of organisms and their interrelations. As is well known, he gave an explanation differently to Paley's external intelligence that designs all these facets of life - instead he claimed that natural selection, a process like Adam Smith's "hidden hand" explanation for the functioning of economies, was enough to explain adaptation.
I have long thought that Darwin was too much in thrall to the traditions…
razib | February 16, 2008When the adaptive acceleration story hit the wires I started wondering if population size wasn't the only parameter that might have changed in the past 10,000 years. To make it short, perhaps a small-world network model is more much accurate now with the rise of complex societies (the complexity being contingent upon the parasitism of elites upon the marginal surplus productivity of the larger population sizes due to agriculture). I assume that in the hunter-gatherer world occurrences such as the burial of a Swiss man at Stonehenge in the British Isles 4,300 years ago were not unheard of;…
razib | February 16, 2008If you enjoyed William D. Hamilton week, I highly recommend Lee Alan Dugtakin's books. The Imitation Factor is a book length exposition on research which shows how many organisms use socially embedded information in making their decisions; if you want to understand the utility of conformity it's enlightening. The Altruism Equation consists of seven biographical sketches of prominent thinkers in social biology; worth checking out just for the chapter on J. B. S. Haldane. That being said, the prose is definitely workmanlike as opposed to masterful, A Reason for Everything and The Darwin Wars…
evolvingthoughts | February 16, 2008
A real journalist reviews a media conference held for the new pro-ID film Expelled:
Freedom of expression is unseemly at an Expelled press conference. There was no give-and-take, no open marketplace of ideas, in fact, scarcely any questions at all. Ruloff and Stein batted one softball after another out of the park from those posed by Paul Lauer, a representative of the film's public relations firm. Questions from non-employees had to be submitted by email. Lauer (or somebody at his firm) screened them.
I'm not sure whether Thomas Aquinas handled media inquiries this way. I'll have my…
gregladen | February 16, 2008Yet another group of slack jawed yokels in some backwater school district want to force their religious beliefs on children in their local school district. This time it's Nassau County.
"The theory of evolution falls short here since it cannot be observed, hasn't been repeated and cannot be tested," Marjorie Ramseur told School Board members. "I applaud you for taking a stand on this issue. If you're going to teach evolution, please teach all of it."
[source]