evolution
clock | August 15, 2007John Wilkins just published a paper (..."a review of the centenary festschrift for Mayr...") and got a book accepted for publication (the book grew out of series of excellent blog posts about species definitions - who says that blogging is bad for your health?)
Congratulations!
evolvingthoughts | August 14, 2007
I have a book forthcoming, Species definitions: a sourcebook from antiquity to today, which gives and commentates definitions of "species" in logic and biology for 2,500 years, from Plato to Templeton and beyond. It's designed as a reader for scholars to see how the notion[s] have evolved separately in the logical definitional sense - for Aristotle, eidos, which we translate as "form", "species", and "kind", was a logical term, not a biological one, which had to wait until the 16th century, and even then they were distinct notions.
I argue in the commentaries that there was nothing…
evolvingthoughts | August 14, 2007
I normally don't respond the to IDiocy of Uncommon Dissent, but John Lynch, may he rot in purgatory for a thousand years, has made me. As usual, I won't dignify it with links. If you are that interested you can find it.
There are two items: one is by DaveScot, who argues (!) that because Popper's falsification hypothesis means that until we find non-white swans, a hypothesis that swans are white stands, we should somehow assume that Intelligent Design stands as a scientific view. This is silly for a couple of reasons. One is that we have got counterinstances to the need for ID to explain…
loom | August 13, 2007Parasitoid wasps (or rather, one group of them called the Ichneumonidae) are the subject of one of Charles Darwin's most famous quotations: "I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of caterpillars."
Scientists have learned a lot more about parasitoid wasps since Darwin wrote about them in 1860, and their elegant viciousness is now even more staggering to behold. Not only do they devour their hosts alive from the inside out, but they also manipulate the…
grrlscientist | August 13, 2007tags: science, nature, medicine, tangled bank, blog carnivals
Aaand yet another blog carnival was published today. This time, the 86th edition of the Tangled Bank blog carnival is now available. They also include a submission from me, so be sure to go over there to see what all the noise is about.
clock | August 13, 2007A serious one, for advanced courses. I held it in my hands the other day (Jonathan Eisen brought a copy to Scifoo to show). I hope to get one soon. Check it out at its homepage and order yourself a copy. It looks great!
clock | August 13, 2007I may be a little late to this, but better late than never. Laelaps has penned one of those rarities - an exceptionally detailed historical summary of the way people's understanding of human origins changed over time. Bookmark and read when you have time to really focus.
evolvingthoughts | August 12, 2007
I have a review of the centenary festschrift for Mayr, published by the National Academies of Science, in the latest Biology and Philosophy here. I worked pretty hard on this one, so it's more than your average dashed off review article...
Hey, Jody; Fitch, Walter M.; Ayala, Francisco J., eds. 2005. Systematics and the origin of species: On Ernst Mayr’s 100th Anniversary. Washington, DC: National Academies Press. Pages: 367 + xiii. ISBN: 0-309-09536-0
evolvingthoughts | August 11, 2007
Laelaps has a very nice essay that ranges from the number of ribs humans have, the book of Genesis, creationism, and the variety of stories told about human evolution from the nineteenth century to now. Go read it. It's one of the few blog posts in which you'll read of petrified testicles...
[HT: Afarensis]
loom | August 11, 2007I think that the next time I'm asked to talk about human evolution at 7:38 a.m. on a news show, I'm going to shave my head the night before. Nothing undermines the authority of a science writer like a serious case of bed head. See it here (or paste this address into Windows Media Player's URL), and take pity.
grrlscientist | August 11, 2007tags: researchblogging.org, osteocalcin, type 2 diabetes, obesity, bones, medicine
Even though bones seem to be metabolically inactive structures, nothing could be further from the truth. In fact, bones are rebuilt constantly through the action of cells known as osteoblasts while old bone is destroyed by other cells known as osteoclasts. Bones also produce red and white blood cells, help maintain blood pH and store calcium. However, exciting new research has shown that bones also act as an endocrine organ. Not only do bones produce a protein hormone, osteocalcin (pictured), that regulates…
evolvingthoughts | August 10, 2007
Rob Wilson has a new entry up at the Stanford Encyclopedia of Philosophy, entitled "The Biological notion of an individual". It discusses an interesting problem, one that goes back to discussions by Julian Huxley in 1911. What is an individual in biology?
The term "individual" means, etymologically, that which is not divisible. Of course we can divide up organisms, but if we do this physically, they immediately thereafter cease to be the organism. Except... there are colonial organisms that can be so divided - sponges, hydras, slime molds, and so on. To make matters worse (much worse, as…
pharyngula | August 10, 2007Here is an excellent article on the biology of sexual orientation. We all know this is a contentious issue — are we born with an orientation, or is it a 'choice' that people make? — and the article just lays the facts out for us and points out some of the lacunae in our knowledge.
First, I'll confess to my own position on that nature-nurture debate: it's both and it's neither, and the argument is misplaced. There is no template on the Y chromosome that triggers a sexual response when Pamela Anderson enters the visual field, but there almost certainly are general predispositions that are a…
pharyngula | August 9, 2007Two new Homo fossils are described in this week's Nature, and here they are.
This is KNM-ER 42700. It's a very well preserved brain case, it has been dated to 1.55 million years ago, and it has been positively identified as belonging to Homo erectus. It's a little unusual in being particularly small, but otherwise, definitely H. erectus.
a, Anterior, b, left lateral, d, superior and e, inferior views of KNM-ER 42700 (scale bar, 5 cm).
This is KNM-ER 42703. It's a broken maxilla, or upper jaw, and it has been dated to 1.44 million years ago — it's over 100,000 years more recent than the KNM-…
mikethemadbiologist | August 9, 2007...the signal peptide? Interesting. I'll start at the beginning.
One of the few bright spots regarding the problem of antibiotic resistance is that resistance typically infers a fitness cost to the bacterium, at least initially. In other words, the resistant strain usually grows slower than a nearly identical sensitive strain*. While compensatory mutations can lower or eradicate this 'cost of resistance', it is thought that resistance can't increase initially without favorable selective conditions--antibiotic use--due to the cost of resistance.
We'll need a little background about…
jrosenhouse | August 8, 2007Today's New York Times has this interesting article about some recent hominid fossil finds. Alas, it falls into the familiar trap of reporting every mundane find as if it is a scientific revolution:
Two fossils found in Kenya have shaken the human family tree, possibly rearranging major branches thought to be in a straight ancestral line to Homo sapiens.
Scientists who dated and analyzed the specimens -- a 1.44 million-year-old Homo habilis and a 1.55 million-year-old Homo erectus -- said their findings challenged the conventional view that these species evolved one after the other. Instead…
razib | August 8, 2007The New York Times has an article up reiterating the fabled "bushiness" of hominid phylogenetic trees:
Scientists who dated and analyzed the specimens -- a 1.44 million-year-old Homo habilis and a 1.55 million-year-old Homo erectus -- said their findings challenged the conventional view that these species evolved one after the other. Instead, they apparently lived side by side in eastern Africa for almost half a million years.
My knowledge of bones is not strong, so I leave it to John Hawks or Kambiz to decompose the details. That being said, the big picture is that this is another strike…
evolvingthoughts | August 7, 2007
I have a soft spot for Herbert Spencer [see also here]. Supposedly the founder of social Darwinism and the precursor to American libertarianism and justifier of the robber barons of the Gilded Age, he has been the whipping boy of progressives and anti-evolutionists alike. Ever since Richard Hofstadter fingered him as the source of rough individualism and eugenics in his Social Darwinism in American Thought in 1943, Spencer has been the evil demon of philosophy, political thought, and evolution. But a recent article in The New Yorker occasioned by a new book Herbert Spencer and the Invention…
oracknows | August 7, 2007After a long run of arguing against global warming and indoor smoking bans, it appears that our favorite Libertarian comic with a penchant for bad arguments and ad hominem attacks on scientists has temporarily left the field of blog combat in a huff of "giving up" that reminds me of a certain Black Knight telling a certain King that he's not beaten and that it's "just a flesh wound." I'm not worried; I'm sure he'll be back whenever he returns from his vacation to speak for himself. In the meantime, while the blog silence is golden, I'd like to step back a minute. I don't want to rehash old…
purepedantry | August 6, 2007It's mad, I tell you, madddd! Mad scientists these days. Always going around saying, "Hey, you know how that animal could be better? If it had another head. Muahahaha!"
Anyway, the (possibly mad) scientists Wolfgang Jakob and Bernd Schierwater wanted to know more about the genes that determine the body plan of multicellular organisms. In mammals, these genes are called Hox genes, and in organisms that have circular symmetry like jellyfish they are called Cnox genes. We know that these genes broadly pattern the body plan of multicellular organisms because in a variety of settings if you…