Life Sciences
voltagegate | September 1, 2007The bints, it turns out, have an interesting evolutionary history.
Recent molecular analysis of the order Carnivora (dogs, cats, bears, seals, bints, etc.) places all subsequent species into two clades (branches): the Caniformia and the Feliformia.
The Caniformia clade contains a staggering array of animals - dogs, bears, seals, martins, pandas, otters and walruses - but interestingly enough, dogs (canids) were the first to split from the group (from the Arctoids), something like this:
The other side of the clade, the Feliformia, starts with the split of Nandinia, the African palm civet.…
tqa | August 30, 2007
Michael Majerus has spent countless hours conducting research on the Peppered Moth (Biston betularia). He's observed them in the field, bred them in the lab, watched them get eaten by things, kept careful count of the things that he's seen, and, recently, given a talk about his findings. Jonathan Wells has spent, to the best of my knowledge, absolutely no time doing any actual research on natural selection or moths, but that certainly didn't stop him from launching a full-throated attack on Majerus.
In this attack, Wells manages to misrepresent a lot of things. This should come as no…
dmunger | August 28, 2007
We can recognize the faces of our friends very quickly from just a snapshot. Within 150 milliseconds of being flashed a photo, brain signals respond differently to photos containing animals than photos with no animals. We can categorize scenes as "beach," "forest," or "city" when they are flashed for even shorter periods.
But we also get a great deal of information from the motion of people and animals. We can identify our friends and family members just from a point-light display of them walking. We can also detect the emotions of point-light faces, and even the species of point-light…
grrlscientist | August 27, 2007tags: Birds in the News, BirdNews, ornithology, birds, avian, newsletter
Bald Eagle, Haliaeetus leucocephalus, preparing to land on its nest, Kodiak Island National Wildlife Refuge, Alaska.
Image: US Fish and Wildlife Service.
Birds in Science
Here's a question for all of you: whose offspring would do better; those raised only by their parents, or those raised by their parents in addition to an extended family group? A research team led by Andrew F. Russell of the University of Sheffield in England recently asked that very question in their research of superb fairy-wrens, a species where…
jstemwedel | August 24, 2007 The other day I received a DVD made by Americans for Medical Progress called Physicians - Speaking for Research. (They indicate on their site that the DVDs are free for the asking.)
This is a DVD aimed at physicians, rather than at research scientists or the general public. However, the aim of the DVD is to help physicians to be better at communicating with the general public (primarily their patients, but also their family members and neighbors) about the role animal research has played in medical advances upon which we depend today, and the continued importance animal research will…
pharyngula | August 24, 2007
Some of you may have never seen an arthropod embryo (or any embryo, for that matter). You're missing something: embryos are gorgeous and dynamic and just all around wonderful, so let's correct that lack. Here are two photographs of an insect and a spider embryo. The one on the left is a grasshopper, Schistocerca nitens at about a third of the way through development; the one on the right is Achaearanea tepidariorum. Both are lying on their backs, or dorsal side, with their legs wiggling up towards you.
There are differences in the photographic technique — one is an SEM, the other is a DAPI-…
clock | August 22, 2007First Finding Of A Metabolite In One Sex Only:
Researchers at the University of Illinois at Chicago have discovered a chemical compound in male blue crabs that is not present in females -- the first time in any species that an entire enzyme system has been found to be activated in only one sex.
How To Share A Bat:
New research shows how different species of plants evolve unique floral adaptations in order to transfer pollen on different regions of bats' bodies, thus allowing multiple plant species to share bats as pollinators.
Global Warming Threatens Moose, Wolves:
Global warming is…
clock | August 22, 2007There are 30 new papers published in PLoS ONE this week. Here are a couple of my picks (under the fold). You know the drill, go read, rate, annotate and comment:
Marburg Virus Infection Detected in a Common African Bat by Jonathan S. Towner, Xavier Pourrut, César G. Albariño, Chimène Nze Nkogue, Brian H. Bird, Gilda Grard, Thomas G. Ksiazek, Jean-Paul Gonzalez, Stuart T. Nichol and Eric M. Leroy:
Identification of the natural reservoirs of Marburg and Ebola viruses is essential in combating the hemorrhagic fever outbreaks that they cause. This study reports Marburg virus-specific RNA and…
grrlscientist | August 22, 2007tags: researchblogging.org, evolution, social behavior, cooperative breeding, environment, global warming, climate change, African starlings, birds
Superb starling, Lamprotornis superbus, a cooperative breeding savanna dweller that is abundant throughout northeast Africa.
Image: Dustin R. Rubenstein [larger]
Postponing one's own reproductive efforts to help other individuals raise their offspring might seem like a bad choice, evolutionarily speaking. But cooperative breeding, as this behavior is known, is fairly common in the animal kingdom, although the reasons underlying the evolution…
pharyngula | August 17, 2007
I just finished Sean B. Carroll's Endless Forms Most Beautiful: The New Science of Evo-Devo the other day, and I must confess: I was initially a bit disappointed. It has a few weaknesses. For one, I didn't learn anything new from it; I had already read just about everything mentioned in the book in the original papers. It also takes a very conservative view of evolutionary theory, and doesn't mention any of the more radical ideas that you find bubbling up on just about every page of Mary Jane West-Eberhard's big book. One chapter, the tenth, really didn't fit in well with the rest—the whole…
sheril | August 16, 2007I've received several emails voicing concern over fishing down food webs since posting last week about the Yangtze River Dolphin: the first cetacean species likely driven to extinction by human activity. Just remember, it's not a dismal picture when you hold the Montgomery Burns perspective!
Keeping economics in mind, there's arguably reason to question whether we should fret over the oceans' dwindling and altered stocks. Human tastes are malleable, so we adapt to what industry supplies. For example, lobster and skate - traditionally the 'poor fisherman's dinner' - are now featured at NYC's…
clock | August 14, 2007Navigation: Using Geometry To Navigate Is Innate, At Least For Fish:
Many animals, including humans, frequently face the task of getting from one place to another. Although many navigational strategies exist, all vertebrate species readily use geometric cues; things such as walls and corners to determine direction within an enclosed space. Moreover, some species such as rats and human children are so influenced by these geometric cues that they often ignore more reliable features such as a distinctive object or colored wall.
This surprising reliance on geometry has led researchers to suggest…
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…
voltagegate | August 13, 2007"Without knowing it, we utilize hundreds of products each day that owe their origin to wild animals and plants. Indeed our welfare is intimately tied up with the welfare of wildlife. Well may conservationists proclaim that by saving the lives of wild species, we may be saving our own."
- Norman Myers
jlynch | August 11, 2007ABC (Australia) is reporting that the Yangtze River dolphin or baiji (Lipotes vexillifer) may not be definitely extinct after all (see here and here). Wang Ding - who headed the survey team - is reported as saying:
This is only one survey and...you can’t have a sample in a survey, so you cannot say the baiji all is gone by the result of only one survey. For example, there is some side channels or some tributaries [where] we cannot go because of a restriction of navigation rules, and also we don’t survey during the night-time so we may miss some animals in the Yangtze River. ...
I’m pretty…
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…
sheril | August 9, 2007They say extinction is the only real certainty. Species are constantly blinking in and out of existence. This may or may not be of concern depending on your scale of interest. In 2007 we're doing all sorts of things to pillage and plunder life on this incarnation of planet earth, but of course 2007 is a rather arbitrary number.. for even if space and time do exist, who's counting and to what end? In any event, I do remain interested in the here and now because that's where I live. You do too. So it's worth taking note when Biological Letters reports the first probable human-caused…
denialism | August 8, 2007Responding to a commentor on a thread about animal rights, I again encountered this funny view of nature that some people have. Two sentences in particular just struck me as being out of touch with reality.
The alternative may be to try to live in harmony with nature.
...
Trying to dominate nature has only caused suffering. There are alternatives.
Where do people get this idea that nature is our friend? Hippies drive me nuts. Not only is this just totally unrealistic, but I think it also reflects a fundamental ignorance of biology, history, and the basic infrastructure of our society. I…
denialism | August 8, 2007No.
However, there is never a shortage of crankery from Mike Adams who asserts Microwave ovens destroy the nutritional value of your food. There may be too much idiocy here to address but let's get started.
The rise of widespread nutritional deficiencies in the western world correlates almost perfectly with the introduction of the microwave oven. This is no coincidence. Microwave ovens heat food through a process of creating molecular friction, but this same molecular friction quickly destroys the delicate molecules of vitamins and phytonutrients (plant medicines) naturally found in foods.…
clock | August 7, 2007Glia Play An Important Role In Circadian Timing:
Glial cells of the nervous system, once thought to function strictly as support cells for neurons, are now thought to actively modulate them. Providing further evidence in support of this theory, researchers at the Department of Neuroscience and the Center for Neuroscience Research (CNR) at Tufts University School of Medicine (TUSM) recently identified a specific population of glial cells that is required for the control of circadian behavior in Drosophila (the fruit fly). Their findings, which confirm and extend their earlier work, are…