evolution
evolgen | April 27, 2007This week's phylogeny comes from this paper on molecular dating of speciation events. I won't be addressing molecular dating per se, but I will be dealing with what molecular clocks tell us. Like, do they actually reveal the speciation time of a pair of species?
The divergence date of a pair of species can refer to two things: when the two populations became two species (no longer exchanging alleles) or when the two genetic lineages split. The splitting of genetic lineages happens prior to the speciation event. That's because within a population there is variation throughout the genome. It's…
voltagegate | April 27, 2007I love to read old science books, especially those that discuss biology before the discovery of DNA (aka the "mechanism of heredity"). I found this particular book in a small antique store in Pennsylvania and was struck by a small passage affirming the viability of evolution.
From The Outline of Science: A Plain Story Simply Told, published in 1937:
The Evolution-idea is a master-key that opens many doors. It is a luminous interpretation of the world, throwing the light of the past upon the present. Everything is seen to be an antiquity, with a history behind it - a natural history, which…
oracknows | April 26, 2007On May 5 New York City will witness what will perhaps be the most unintentionally hilarious spectacle of two fundamentalists making utter fools of themselves:
MEDIA ADVISORY, April 26 /Christian Newswire/ -- After ABC ran a story in January about hundreds of atheists videotaping themselves blaspheming the Holy Spirit, best-selling author Ray Comfort contacted the network and offered to prove God's existence, absolutely, scientifically, without mentioning the Bible or faith. He and Kirk Cameron (co-hosts of an award-winning Christian TV program) challenged the two originators of the "…
purepedantry | April 26, 2007The Economist has a great article summarizing all the ways in which the debate between evolution and religion has gone global. It also does a good job of analyzing the different strains within the American debate, depicting it as much less monolithic:
Even in the United States, defenders of evolution teaching do not see their battle as won. There was widespread dismay in their ranks in February when John McCain, a Republican presidential candidate, accepted an invitation (albeit to talk about geopolitics, not science) from the Discovery Institute. And some opponents of intelligent design…
cmooney | April 26, 2007From his blog:
Camp 3, which is perhaps not as well defined, promotes the inclusion of theistic elements in evolutionary biology, in some cases explicitly in other cases as a kind of "fill in the blank," in order to provide a better approach to "framing" evolutionary biology. (Notice the closeness between the word "blank" and the word "gap.")
Or at least, this is what they say. Explicit requests to ask them to clarify this key point have been left unanswered to my knowledge. Which is very worrisome, and sometimes makes me think Moran is right about the possibility that Nisbet and Mooney are…
evolvingthoughts | April 25, 2007
Some phrases no science or other journalist should ever write about science:
"could rewrite theories about evolution"
"medical breakthrough"
"scientific breakthrough
Any suggestions (with links, please)?
[ht: What You're Doing is Rather Desperate
evolvingthoughts | April 25, 2007
I am not sure what exactly this is about, but it is being launched tomorrow. It appears to be a website that corrals news and information about the ecology and biodiversity, global warming and so on. I guess we'll have to wait until the launch to find out. The blurb that was sent to me is below the fold.
A dream has finally come true. After four years of hard work, the first of what will someday be thousands of the most trustworthy portals on the Web, is about to launch. It will be free of corporate/commercial bias, and FREE to the public forever!
http://earthportal.org is the result of…
grrlscientist | April 25, 2007tags: Solomon Islands Frogmouth, Rigidipenna inexpectatus, Podargus ocellatus inexpectatus, birds, birding, ornithology
Gone are the days when animals were classified to taxon based solely on bone structure (osteology), body structure (morphometrics) or behavior (ethology), or some combination of these characters. Currently, scientists have a suite of powerful tools for classifying creatures to taxon, and analyses using a combination of these methods is allowing us to come to a deeper understanding of all animal life. As a result of using these techniques, a new species of bird has been…
pharyngula | April 25, 2007This is cool: Simon Conway Morris gave a talk at Baylor, and Cody was there. Conway Morris is a smart fellow who does some very interesting work, and now I learn that he's also a charming speaker — even though I completely disagree with his conclusions, I wish he'd come a little farther north so I could listen to him. I'd most like to hear him talk about Cambrian and pre-Cambrian paleontology, but it sounds like he's instead lecturing specifically on the ideas where he's most wrong, his belief in the overwhelming power of natural selection (or perhaps, design) to drive convergence.…
evolvingthoughts | April 24, 2007
According to Teleology, each organism is like a rifle bullet fired straight at a mark; according to Darwin, organisms are like grapeshot of which one hits something and the rest fall wide.
Thomas Henry Huxley
John Pieret, of Thoughts in a Haystack, has a nice further discussion of this excellent essay of Huxley's, doing what I didn't have the energy to do. Now that he has linked here and I back to him, expect the Internet to roll up in a recursive black hole...
razib | April 24, 2007Erick Trinkaus has a new article in PNAS, European early modern humans and the fate of the Neandertals:
A consideration of the morphological aspects of the earliest modern humans in Europe (more than ~33,000 B.P.) and the subsequent Gravettian human remains indicates that they possess an anatomical pattern congruent with the autapomorphic (derived) morphology of the earliest (Middle Paleolithic) African modern humans. However, they exhibit a variable suite of features that are either distinctive Neandertal traits and/or plesiomorphic (ancestral) aspects that had been lost among the African…
clock | April 23, 2007I never thought that I would link to Razib approvingly, but his recent series of posts about evolution of religion are right on the mark. You can start with today's post and follow the links back to his older posts. A good start for a discussion on the topic.
mikethemadbiologist | April 23, 2007ScienceBlogling Mike Dunford has an interesting post asking whether we should save an endemic Hawaiian plant, the williwilli. It's a good post, but I have two comments, one silly and one serious. The silly comment is that how could anyone let a plant named the williwilli become extinct? It's so damn cute (and is the plural williwillies?) Onto the serious point.
The reason that the williwilli is in trouble is because an invasive, non-native gall wasp is parasitizing the williwilli. Mike writes:
...if the invasive species outcompetes the natives, resulting in the extinction of the native…
razib | April 23, 2007A few weeks ago, Andrew Brown (author of The Darwin Wars) stated:
I'm not sure that Boyer, Atran and Wilson regard their explanations as complementary. I have talked to all three of them about it. My feeling is that while all three of them understand that the explanations might be complementary, they prefer to believe that all the work is done by their preferred model. It's not clear to me how one could decide this point in principle.
He refers to Scott Atran (In Gods We Trust), Pascal Boyer (Religion Explained) and David S. Wilson (Darwin's Cathedral). Atran & Boyer are of very similar…
evolvingthoughts | April 21, 2007
Jonathon Gottschall, in a recent piece in New Scientist (reprinted here) offers what he calls "Literary Darwinism":
Understanding a story is ultimately about understanding the human mind. The primary job of the literary critic is to pry open the craniums of characters, authors and narrators, climb inside their heads and spelunk through the bewildering complexity within to figure out what makes them tick.
Yet, in doing this, literary scholars have ignored the recent scientific revolution that has transformed our understanding of why people behave the way they do. While evolutionary…
evolvingthoughts | April 20, 2007
Yesterday was Willi Hennig's birthday. Hennig invented cladistics (though he called it "phylogenetic systematics"), which is the foundation for all modern taxonomy. Frölich Geburtstag, Willi!
Via Paleoblog.
Oops, my mistake. Philosophers are not always good at math.
evolvingthoughts | April 20, 2007
Yesterday, a commenter asked why I said this and what I meant by it:
All species at a given time have exactly the same evolutionary duration, and on average, probably the same number of ancestral species, as their nearest relatives.
Consider this diagram:
This is an evolutionary tree, or rather part of it since we probably do not know all the branches and taxa that actually occurred in it, for four extant species. The concestor c for A and D is shown by the lowest circle, for A and B and C at the next highest circle, and for B and C at the top circle. The number of previous species to…
razib | April 20, 2007Here is a report on some developments on the hypothesis that humans are very well evolved to run in the heat. A physical anthropologist told me that while cold adapted peoples can acclimate to tropical conditions, heat adapted peoples are not as good at the reverse. That suggested to me that as a tropical species we have deep and extremely powerful adaptations which allow us to tolerate heat, and these adaptations might have other uses that remained advantageous once we moved north into Eurasia.
pharyngula | April 20, 2007I met the fellow who was doing this animated short at the Bell Museum a while back, and now he's let me know the work was done … so here it is for everyone to enjoy.