evolution
razib | June 5, 2009In Natural selection of a human gene: FUT2 I referred to a paper, Signals of recent positive selection in a worldwide sample of human populations (see my earlier review). Now the same group has a follow up paper which takes a slightly different tack, The Role of Geography in Human Adaptation:
Since the beginning of the study of evolution, people have been fascinated by recent human evolution and adaptation. Despite great progress in our understanding of human history, we still know relatively little about the selection pressures and historical factors that have been important over the past…
edyong | June 4, 2009 If you tickle a young chimp, gorilla or orang-utan, it will hoot, holler and pant in a way that would strongly remind you of human laughter. The sounds are very different - chimp laughter, for example, is breathier than ours, faster and bereft of vowel sounds ("ha" or "hee"). Listen to a recording and you wouldn't identify it as laughter - it's more like a handsaw cutting wood.
But in context, the resemblance to human laughter is uncanny. Apes make these noises during play or when tickled, and they're accompanied by distinctive open-mouthed "play faces". Darwin himself noted the laugh-like…
jrosenhouse | June 2, 2009Looks like Richard Dawkins has a new book coming out. It's called The Greatest Show on Earth: The Evidence For Evolution. I can't wait to read it!
But wait a sec? Didn't Jerry Coyne just write that book? Yes, I believe he did. It was called Why Evolution is True. No subtitle needed; the title pretty much says it all.
BOOK FIGHT!
Dawkins certainly wins round one: Better title. Why Evolution is True sounds like the start of a philosophical discussion. The evidence Coyne meticulously documented is not the reason why evolution is true. It is merely the reason we are confident that…
laelaps | June 2, 2009
The exceptionally preserved skeleton of Darwinius, known popularly as "Ida." From PLoS One.
Last month an international team of paleontologists lifted the veil on one of the most spectacular fossils ever discovered; a 47-million-year-old primate they named Darwinius masillae. It was a major event, but not everything went as planned. This fossil, popularly known as "Ida", immediately sparked a controversy about the relationship between science and the media, the ethics of buying fossils from private collectors, and what our distant primate ancestors were like.
Indeed, the media blitz…
oracknows | June 2, 2009Three years ago, I wrote about what I considered to be a fascinating and promising approach to understanding tumor biology. This method involved understanding that tumors are in general made up of a heterogeneous collection of cells. Using this knowledge, it is possible to apply evolutionary principles to cancer, treating a tumor as, in essence, an ecosystem. Indeed, that is exactly what Maley et al did three years ago. They applied evolutionary principles to the precancerous lesion in the distal esophagus known as Barrett's esophagus by examining various measures of population diversity in…
edyong | June 2, 2009In the darkness of the deep ocean, some animals create their own light. Among these is the Hawaiian bobtail squid Euprymna scolopes, which forms a partnership with the luminous bacterium Vibrio fischeri. The squid houses colonies of these bacteria in special light organs, and it can control the brightness and direction of their illuminations. But these organs do much more than produce light - they detect it too.
Deyan Tong from the University of Wisconsin has discovered that the organs generate nervous signals when they sense light and they're loaded with proteins responsible for detecting…
pharyngula | June 1, 2009I admit, I was initially put off by the mere title of Nick Lane's new book, Life Ascending: The Ten Great Inventions of Evolution(amzn/b&n/abe/pwll). I'm one of those many biologists who is adamant about the absence of direction in evolutionary history, and ascending just sounds too much like life climbing the rungs of the ladder of life, so I picked it up in a somewhat prejudicial mood.
Have no fear, though, I was won over. Right at the beginning, he admits that it is a subjective list; his criteria for including the ten chosen evolutionary innovations are that it had to revolutionize…
grrlscientist | May 31, 2009tags: Birdbooker Report, bird books, animal books, natural history books, ecology books
"How does one distinguish a truly civilized nation from an aggregation of
barbarians? That is easy. A civilized country produces much good bird
literature."
--Edgar Kincaid
The Birdbooker Report is a special weekly report of a wide variety of science, nature and behavior books that currently are, or soon will be available for purchase. This report is written by one of my Seattle birding pals and book collector, Ian "Birdbooker" Paulsen, and is edited by me and published here for your information and…
edyong | May 29, 2009When Walt Disney created Mickey Mouse in 1928, he understood the draw that anthropomorphic mice would have. But even Walt's imagination might have struggled to foresee the events that have just taken place in a German genetics laboratory. There, a group of scientists led by Wolfgang Enard have "humanising" a gene in mice to study its potential relevance for human evolution.
The gene in question is the fascinating FOXP2, which I have written extensively about before, particularly in a feature for New Scientist. FOXP2 was initially identified as the gene behind an inherited disorder that…
razib | May 28, 2009
Nick Wade in The New York Times reports on new research where they inserted human FOXP2 genes into the mouse genome. Here are some of the findings:
Despite the mammalian body's dependence on having its two FOXP2 genes work just right, Dr. Enard's team found that the human version of FOXP2 seemed to substitute perfectly for the mouse version in all the mouse's tissues except for the brain.
In a region of the brain called the basal ganglia, known in people to be involved in language, the humanized mice grew nerve cells that had a more complex structure and produced less dopamine, a chemical…
razib | May 27, 2009Scientific American has a long piece reviewing the recent genetic insights into the origins and development of the most awesome pets of all:
It is by turns aloof and affectionate, serene and savage, endearing and exasperating. Despite its mercurial nature, however, the house cat is the most popular pet in the world. A third of American households have feline members, and more than 600 million cats live among humans worldwide. Yet as familiar as these creatures are, a complete understanding of their origins has proved elusive. Whereas other once wild animals were domesticated for their milk,…
ejohnson | May 26, 2009
In this week's episode of Science Saturday, John Horgan chats with primatologist Richard Wrangham about two features that define humanity: violence and cooking. They compare chimpanzee aggression and human warfare, discuss the ancient origins of food preparation, assess the raw food diet craze, and explore how cooking has shaped the sexual division of labor in human society.
laelaps | May 26, 2009
The skull of a tarsier, from The Descent of Primates.
At the turn of the 20th century evolutionary biologists faced a significant problem. In 1859 Charles Darwin had expounded the mechanism of evolution, and Eugene Dubois' discovery of "Pithecanthropus" (known as Homo erectus today) illustrated that humans had evolved over time, but the broad outline of human evolution was almost entirely a mystery. There was no doubt that we had evolved from some ancient group of primates, but one of the most frustratingly difficult to resolve questions was what our earliest primate ancestors were like.…
razib | May 26, 2009On this week's Science Saturday John Horgan interviews Richard Wrangham. The second half of the conversation focuses on Wrangham's new book, Catching Fire: How Cooking Made Us Human. I've heard pieces of the arguments mooted in the back & forth before, but it looks like in this book they're all brought together. Humans are a large animal with a very small gut, so we need to maximize the bang-for-the buck when it comes to what we eat. Unlike gorillas and to a lesser extent chimpanzees we just aren't able to process enough low quality vegetable matter to keep ourselves going. Part of this…
grrlscientist | May 24, 2009tags: Birdbooker Report, bird books, animal books, natural history books, ecology books
"How does one distinguish a truly civilized nation from an aggregation of
barbarians? That is easy. A civilized country produces much good bird
literature."
--Edgar Kincaid
The Birdbooker Report is a special weekly report of a wide variety of science, nature and behavior books that currently are, or soon will be available for purchase. This report is written by one of my Seattle birding pals and book collector, Ian "Birdbooker" Paulsen, and is edited by me and published here for your information and…
grrlscientist | May 24, 2009tags: religion, atheism, godlessness, Science is the Dumbest Religion, humor, funny, satire, edward current, streaming video
This video asks the important question: Have scientists really found the missing link? Or are Darwinianists just blindly worshipping roadkill again? [3:23]
pharyngula | May 22, 2009Oh, man. I'm willing to keep saying that Darwinius masillae was an important discovery, but the PR machine is making it hard to do so without cringing. Carl Zimmer has the History Channel ad for their program on it.
Oh. My. Dog. "The most important find in 47 million years"? "A global event: this changes everything"? This is not helping. It is inflating a good discovery beyond all reason, and when the public hears the creationists declare that it's one fossil of a monkey-like creature, and they're right, it's going to damage the credibility of science.
Seed Media has a bit of a scoop: they'…
laelaps | May 22, 2009
The exceptionally preserved skeleton of Darwinius, known popularly as "Ida." From PLoS One.
.
It has been three days now since an international team of paleontologists promised to deliver the change we need change everything, but when I woke up this morning I was pleased to find that things had still not gone "Bizarro World" around here. There is still a lot going on with Darwinius (better known as "Ida"), though, and while I am sure we will still be talking about her for some time to come I wanted to take a moment to step back and answer a few questions that keep cropping up about this…
grrlscientist | May 21, 2009tags: book review, Why Evolution is True, evolution, creationism, religion, scientific method, Jerry Coyne
Considering the plethora of books about evolution out there, is it really necessary to publish yet another one? What can another book about evolution have to offer that previous books have not provided? This new book not only presents the latest information about evolution to come to light, but it also responds to the most recent attacks made upon this branch of scientific knowledge. The book, Why Evolution is True (NYC: Viking; 2009) by Jerry Coyne, is the most up-to-date and one of the…
mikethemadbiologist | May 21, 2009...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…