Life Sciences
clock | February 20, 2007Storing Digital Data In Living Organisms:
DNA, perhaps the oldest data storage medium, could become the newest as scientists report progress toward using DNA to store text, images, music and other digital data inside the genomes of living organisms. In a report scheduled for the April 9 issue of ACS' Biotechnology Progress, a bi-monthly journal, Masaru Tomita and colleagues in Japan point out that DNA has been attracting attention as perhaps the ultimate in permanent data storage.
More.....
Epigenetics To Shape Stem Cell Future:
Everyone hopes that one day stem cell-based regenerative…
tetrapodzoology | February 19, 2007
If you like amphibians and non-avian reptiles, Britain is a crappy place to live: we have just three native lizard species, three snakes, three newts, two toads and two frogs. But do we have a few more: are various 'neglected natives' lurking in our midst?
This depauperate herpetofauna mostly owes itself to the fact that Britain was glaciated for most of the time that it was connected to the European mainland, and by the time conditions were more equable there was a window of just a few thousand years before (at about 7000 years ago) the English Channel formed. As a result of all this the…
loom | February 19, 2007Darwin gave a lot of thought to the strangest creatures on this planet, wondering how they had evolved from less strange ancestors. Whales today might be fish-like warm-blooded beasts with blowholes and flukes, but long ago, Darwin argued, their ancestors were ordinary mammals that walked on land with legs. His suggestion was greeted with shock and disbelief; neverthless, scientists have found bones from ancient walking whales. Humans, Darwin argued, evolved from apes, most likely in Africa where chimpanzees and gorillas are found today. And today scientists have found about twenty different…
clock | February 19, 2007Light-sensitive Protein Found In Many Marine Bacteria:
New light has been shed on proteorhodopsin, the light-sensitive protein found in many marine bacteria. Researchers at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley have demonstrated that when the ability to respire oxygen is impaired, bacterium equipped with proteorhodopsin will switch to solar power to carry out vital life processes.
More....
The Last Wild Hunt: Deep-sea Fisheries Scrape Bottom Of The Sea:
An international team of leading fisheries…
evolvingthoughts | February 19, 2007
A recent report noted that studies that rely on evolutionary processesto explain, say, antibiotic resistance among pathogens, tend not to use the "E-word" in medical journals, instead using terms like "emerging", "spreading" and "increasing". The reason appears to be the bad connotations "evolution" has in American contexts.
There is much misunderstanding of this term, and people often pack a lot of differing concepts under it. Consider this rant by a creationist in The American Spectator: there are "six types of evolution" according to him. They are cosmic evolution, chemical evolution,…
evolvingthoughts | February 16, 2007
As everyone is tired now of hearing, Intelligent Design booster Michael Behe has argued there is an "irreducible complexity" in some biological processes that means they cannot have evolved. The basic logic is pretty simple - if a system needs all its parts, then the lack of any part means it would be nonfunctional. This means, he says, that for it to have evolved, those other parts would be twiddling their thumbs evolutionarily, until all the parts are in place.
The incredibly smart, handsome and active Ian Musgrave has a piece on Panda's Thumb on Behe's key example, the clotting cascade…
tetrapodzoology | February 16, 2007
Continuing the vampire theme, I here want to discuss another of those really, really interesting things about vampire bats: namely, how did their blood-feeding behaviour evolve in the first place?
First off, a big thank you to everyone who's been visiting, commenting and generally saying nice things. The Speculative Zoology post in particular generated a lot of recent interest, and as of yesterday Tetrapod Zoology was the third most-hit site in the scienceblogs community (though still way way behind Pharyngula of course). For some reason I'm unable to post new comments on the Speculative…
clock | February 16, 2007'Regressive Evolution' In Cavefish: Natural Selection Or Genetic Drift:
"Regressive evolution," or the reduction of traits over time, is the result of either natural selection or genetic drift, according to a study on cavefish by researchers at New York University's Department of Biology, the University of California at Berkeley's Department of Integrative Biology, and the Harvard Medical School. Previously, scientists could not determine which forces contributed to regressive evolution in cave-adapted species, and many doubt the role of natural selection in this process. Darwin himself, who…
tetrapodzoology | February 14, 2007
Imbued with god-like powers, the ever-inspirational Mathew Wedel, aka Dr Vector, has wondered what sort of experiments he might play with the biosphere in order to observe the evolutionary results. Given that I just posted an article the other day on Godzilla, it would be a good idea to avoid the whole speculative zoology area for a while. After all, I don't want to get a reputation. But I have to strike while the proverbial iron is hot and, don't worry, we'll be back to rodents, passerines and small, dull brown lizards soon enough. Sticking only with tetrapods (of course), what neat…
clock | February 14, 2007Female Antarctic Seals Give Cold Shoulder To Local Males:
Female Antarctic fur seals will travel across a colony to actively seek males which are genetically diverse and unrelated, rather than mate with local dominant males. These findings, published in this week's Nature, suggest that female choice may be more widespread in nature than previously believed and that such strategies enable species to maintain genetic diversity.
How Badger Culling Creates Conditions For Spread Of Bovine Tuberculosis:
A stable social structure may help control the spread of bovine tuberculosis (TB) among badgers…
grrlscientist | February 12, 2007
Western honeybee, Apis mellifera.
Image: William Connolley.
When I was in graduate school, I nearly decided to study social bees for my dissertation work, but in the end, I decided to pursue my greatest passion, birds. However, despite this, bees have long been a favorite animal of mine, and if I had my own place to live, I would be keeping social and semi-social bees of various species, particularly native species.
But it looks like the nation's bees are not doing very well: something is killing them. The domesticated western honeybee, which does much of the pollintation of crops, has…
tfk | February 12, 2007198 years ago, Charles "Chuck D." Darwin was born to an English physician who had married into the family famous for Wedgwood china. Halfway around the world, in a log cabin on the frontier, young Abraham Lincoln was born. Those two births changed the world, bringing forth a set of ideas that changed how we all see the world.
Darwin's idea was simplicity itself, once he recognized it. Animals and plants all differ, and those differences are passed from generation to generation. Some of that variation improves an animal or plant's prospects in life, other variations limit the prospects of…
pharyngula | February 10, 2007In the comments, Art Hunt passes along a short analysis from Patrick Frank of the instances of Haeckel's work in a number of biology texts from 1923 to 1997. Even the oldest was critical of Haeckelian recapitulation, and only a minority used Haeckel's figure at all.
I looked at 15 books in total. Where Haeckel's drawings appeared, that fact is noted. Where comment on Haeckel or his law is given, I have quoted the text faithfully, or in one case summarized, to give the flavor of the commentary.
Of the 15 books, only 5 show Haeckel's drawings, two in whole, three in part.
Of those 5, only…
jstemwedel | February 9, 2007Last weekend, the sprogs and I were delighted to attend a late Australia Day/early Darwin Day party. Our hosts apologized for "not having much interesting kid-stuff" on hand. Little did they suspect that the abundance of cookies (not just ANZAC cookies, but rolled ginger and lemon cookies in the shapes of kangaroos and giant Galapagos tortoises), and of cute stuffed animals native to Australia, and of art supplies, would keep the Free-Ride offspring more than happy.
Did I mention that the art supplies included Australia-themed stickers? Terribly useful to have road signs so your duck-…
cmcclain | February 8, 2007
The sea cucumber, Scotoplanes globosa, at 1500m in Monterey Canyon.
Just Science Entry #4
Not giant squid or man eating sharks...megafauna, those organisms those organisms large enough to be caught in trawls or seen in photographs or video. (fish, crabs, lobsters, starfish, urchins, sea cucumbers, sponges, corals, etc.). This is different than the macrofauna (those organisms retained on a small screen mesh sieve, cannot see them with the naked eye) and meiofauna (really small organisms you cannot see with the naked eye like forams, copepods, nematodes).
For more than a century the ocean…
razib | February 7, 2007Why do humans cooperate? Why do we behave "altruistically"? These are the sort of "big" questions which the human sciences explore. From the vantage point of evolutionary biology there has been a long history of exploring, and attempting to explain, altruistic behavior. And yet such questions weren't always considered of great value, the great W.D. Hamilton was discouraged from his exploration of this topic by his department head. At one point he took up carpentry to furnish for himself an income while he pursued his science in his spare time, so pessimistic was he about receiving academic…
clock | February 7, 2007Human Proteins Evolving Slowly Thanks To Multitasking Genes:
Many human proteins are not as good as they might be because the gene sequences that code for them have a double role which slows down the rate at which they evolve, according to new research published in PLoS Biology. By tweaking these dual role regions, scientists could develop gene therapy techniques that produce proteins that are even better than those found in nature, and could one day be used to help people recover from genetic disorders.
More....
Sea Creature's Toxin Could Lead To Promising Cancer Treatment:
A toxin derived…
grrlscientist | February 5, 2007
Bateleur Eagle, Terathopius ecaudatus,
photographed at a zoo in North Carolina. Click image for a much larger view.
Image appears here with the kind permission of the photographer, Chris Losinger.
Birds in Science
Like bacteria, various farm animals have been cloned to produce a variety of protein drugs that benefit humans. These protein drugs can counteract medical conditions such as anemia and diabetes and even some cancers. However, these cloned animals are expensive, large, and most take years before they can produce these desired protein drugs in sufficient commercially-viable…
razib | February 5, 2007The conventional Mendelian
model for diploid organisms assumes that the expression of an autosomal
allele within an individual should be invariant of its sex of origin,
that is, whether it is inherited from the father or the mother.
This model is incorrect for a subset of alleles across many taxa, in
particular mammals. In 1989 David Haig and Mark Westoby outlined
the evolutionary rationale for parent specific gene expression.1
In 1992 paternal and maternal specific imprinting of the insulin growth
factor 2 and insulin growth factor 2 repressor loci (Igf2,
Igf2r) in mice confirmed their…
clock | February 4, 2007I don't know how many of you check out the constantly growing list of links to posts that cover Basic Terms And Concepts in Science, but you should. Our Seed Overlords are cooperating and will soon set up a place where all those posts will be re-posted, commented upon, edited, etc. - a one-stop shopping for all basic stuff useful, for instance, in teaching at all levels from Kindergarden to Postdoc!
Until then, here is my unofficial list - not the one compiled by Wilkins - that also includes some of my own posts, as well as some of the other people's posts that I found useful in teaching…