evolution
evolgen | December 4, 2007
I previously described where in a genome we would expect to find sexually antagonistic genes. Briefly, depending on whether a gene is male-biased or female-biased and whether beneficial mutations are dominant or recessive, we can predict whether these sexually antagonistic genes will be on X chromosomes or autosomes. As I mentioned in that post, the theoretical results can only be translated into realistic predictions if we have reliable estimates of the relevant parameters. We do not have such estimates, but we can study the distribution of sex-biased genes throughout genomes. The results…
pharyngula | December 3, 2007Here's a useful excercise: can you summarize a key concept in your field in less than a minute? Chris Mims takes a stab at explaining evo-devo — he's not trying to explain the whole field, actually, but the central concept of a master gene. He uses the analogy of a power strip for a transcription factor, which I like quite a bit, and I'm probably going to have to steal it someday.
evolgen | December 3, 2007
Not all animals must have sex with another individual to produce perfectly viable offspring. And neither do humans, thanks to technological breakthroughs in artificial insemination. But what about those critters that do not require masturbation and meat basters to produce babies sans contact with another individual? Remarkably, this is quite common in the animal kingdom, although different animals go about doing it in different ways.
Caenorhabditis elegans, the roundworm that has become a popular model in developmental biology, lives in populations made up almost entirely of hermaphrodites.…
evolvingthoughts | December 3, 2007
Way back in the 1910s, when human evolution was poorly known, some trickster, probably Charles Dawson, its discoverer, set up a hoax: Piltdown man. This was enthusiastically accepted by many British experts because it made Britain, and in particular, England, a leading locale in human evolution. This was the era of Imperial honour and competition, shortly before these powers decided to compete more concretely. Nationalism has always been a factor in evolutionary hypotheses, ranging from Raymond Dart's southern ape, Australopithecus, in South Africa to objections to the discovery by Eugene…
oracknows | December 2, 2007There are certain bloggers who can reliably be counted on to deliver the stupid. We've met several of them over the time this blog's been in existence. One such blogger, the born again Christian named LaShawn Barber, has been particularly good at it, although we've only met her a couple of times before, likening the NAACP to the white nationalist teen duo Prussian Blue as a means of trolling and saying rather odd things about Ted Haggard. Those were bad enough, but now she's even more out of her depth than usual as she decides to pontificate about something about which it is brain-fryingly…
loom | December 1, 2007My bad--for some reason I thought my piece on NPR would air this morning. It was on the news tonight. And you can listen to it here.
loom | November 30, 2007A quick heads-up: I'll be talking about the tree of life tomorrow morning on NPR's Saturday Weekend Edition. The segment will be archived on their "Science Out of the Box" web page. We'll be talking about everything from animals to mushrooms to the unclassifiable viruses that graft the tree of life into a web.
Update: 12/1 10 am: ...or maybe not. As far as I could tell over the breakfast din, the piece didn't run this morning. I'll let you know when and if it does.
Update: 12/1 5:30 pm: The piece just ran. I don't think I made any major gaffes, but fact-check away. Here's where you can listen…
mikethemadbiologist | November 30, 2007Or is it Lazarai? Either way, The New Yorker has an interesting article about recreating extinct viruses. To be precise, the article deals with recreating retroviruses.
Before you get all het up about the Evul Scientists creating a new AIDS or some hooey, most mammalian genomes (and other organisms) are chock full off degenerate--non-functional--retroviruses. Presumably they would up in these genomes by infecting the host, so figuring out what ancient viruses look like can help us figure out how today's viral threats work. While there's some hyperbole in the article, it's still a pretty…
oracknows | November 29, 2007Heard on the radio this morning, a commenter responding to a radio talk show host's pointing out to him that Mike Huckabee doesn't accept evolution as valid. This is as close as I can remember what he said, but the gist is correct:
We disagree on that. But not believing in evolution is something I can overlook. It's not that important. It's not as though he'll have stormtroopers knocking down my door because of it.
Maybe not, but if elected Huckabee would have a huge say over federal educational and biological research policy and funding. Being a creationist, as Mike Huckabee is, to me is an…
scientificactivist | November 29, 2007Dear Texas,
Let me first of all say that despite our differences, I still consider you my home, even if I only get to visit a couple of times a year these days. Friends, family, football: you have it all for me. And, as I watched it get dark here in Oxford around 4 pm this afternoon, I have to admit that I really miss that warm Texas sun.
But, Texas, I have to tell you--pal to pal--that your recent actions have been so stereotypical. I mean, yeah, we get it. You're conservative. Really conservative. And, you like Jesus. A lot. Tell me something new. But now I hear that you forced…
evolvingthoughts | November 29, 2007
The term "radical" is a very loose term. It basically means "something that differs wildly from the consensus" in ordinary usage. So I hope David Williams and Malte Ebach won't take offense if I say that they have a radical interpretation of the nature of classification. In a couple of recent posts - one on Adolf Naef, and one on Molecular Systematics - they have presented some views on classification that do, indeed, differ from the received consensus. So, I need to blather a bit...
The nature of classification is highly contested in biology, let alone the ancillary philosophical…
loom | November 27, 2007I just noticed that in the new issue of the New Yorker Michael Specter has written an article on the viruses in our genome. I wrote about this research in the New York Times a year ago. I haven't had a chance to read the article through yet, but I was mortified to come across this line...
Until recently, the earliest available information about the history and the course of human diseases, like smallpox and typhus, came from mummies no more than four thousand years old. Evolution cannot be measured in a time span that short.
What happened to the New Yorker's legendary fact-checking staff?…
loom | November 27, 2007For my latest "Dissection" column in Wired, I take a look at the tree of life, and the way it changed dramatically thirty years ago this month. To get a sense of what the tree looks like today, I pointed readers to the wonderful interactive tree of life at the European Molecular Biology Lab. But I didn't realize until after I finished the column that when you scroll over the branches of the tree, pictures pop up of species at their tips. Most of the pictures are of assorted chains, blobs, and other microbial portraits. But things get more interesting in the animal kingdom. Iz very nice!
Hat…
razib | November 25, 2007Evolution: What the Fossils Say and Why It Matters is an expansive new book authored by vertebrate paleontologist Donald Prothero and lushly illustrated by Carl Buell. The quality of the plates and illustrations, the binding as well as the texture of the pages, screams out "Coffee Table Book." That's not an insult, but it just reinforces that this isn't a monograph aimed at specialists, rather, it is in large part a manifesto aimed toward the general public. And its high production quality testifies to the fact that it wants to be taken seriously by marrying style with substance.
Though…
clock | November 24, 2007Or, Happy Evolution Day! It's time for a party!
It is easy to look up blog coverage - if you search for "Origin of Species" you mostly get good stuff, if you search for "Origin of the Species" you get creationist clap-trap as they cannot even copy and paste correctly (hence they are better known these days as cdesign proponentsists).
Pondering Pikaia and The Beagle Project Blog were first out of the gate this morning with wonderful posts.
Here is a recent book review of the Origin by someone who knows some biology and another one by someone who does not - both are quite nice and eye-opening.…
pharyngula | November 24, 2007Today is the 148th anniversary of the publication of Charles Darwin's On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. Enjoy those Thanksgiving leftovers!
evolvingthoughts | November 24, 2007
... a book was published that changed the way we thought of biology.
evolgen | November 23, 2007Brian at Laelaps has written a post entitled "What's good for the gander isn't always good for the goose", in which he describes some examples of sexual dimorphism in charismatic vertebrates. Studying the phenotypes of these traits is interesting, but what's happening on the genomic level? That is, how do differences between males and females affect the distribution of genes on chromosomes?
Many of the traits that are beneficial for males are deleterious in females (and vice versa). For example, male sheep with big horns will mate more and leave more offspring, but females with big horns…
evolvingthoughts | November 21, 2007
So now, I think it's worth asking what we really can achieve by doing sociobiological investigations, and some of the traps in previous attempts.
Humans are animals. They are vertebrates, mammals, primates, and apes. Like other animals, their behaviours are formed, constrained, and in most cases fully dependent upon their biology, but the confounding factor in doing sociobiology is the trap of taking one's own culture, the culture of the researcher, as being "normal" and treating all other cultures as less than normal, or primitive, or in some other manner less than worthy, treating biases…