Life Sciences
evolvingthoughts | January 12, 2007
This is the first in an irregular series of basic concepts in science, that I suggested to the Seed Bloggers we might do from time to time. If anyone wants to suggest a revision, because I got it wrong or am unclear, make a comment - this will be revised to make sure it is OK.Clade: this term of art is a new one in biological systematics, or the science of classification, or taxonomy. The word has given its name to a new science of classification: cladistics, which is properly known as phylogenetic systematics.
A clade is, simply expressed, any branch (Greek: klados) of the evolutionary…
clock | January 12, 2007Big-brained Birds Survive Better In Nature:
Birds with brains that are large in relation to their body size have a lower mortality rate than those with smaller brains, according to new research published in the journal Proceedings of the Royal Society B: Biological Sciences. The research provides the first evidence for what scientists describe as the 'cognitive buffer' hypothesis - the idea that having a large brain enables animals to have more flexible behaviours and survive environmental challenges.
The Price Of Vanity: Mating With Showy Males May Reduce Offspring's Ability To Fight Off…
evolvingthoughts | January 11, 2007
Quick... what was Darwin's most popular book? If you answered The Origin of Species, you were wrong. It was his last book, published the year before he died, The Formation of Vegetable Mould Through the Action of Worms With Observation of Their Habits. Darwin noted when he was beginning his career that worms churned up soil, causing heavier objects to sink slowly in the soil. He noted that all soil had passed through the alimentary duct of worms. It started off a fashion of cultivating worms by gardeners that continues to the present day.
Now called "bioturbation", this process has…
pharyngula | January 11, 2007
The Kansas Board of Education is going to be re-evaluating the anti-science standards the formerly overwhelmingly right-wing crazy board had approved—they've since elected more moderate members—and the creationists aren't happy about it. When reading the stories, there was this name that kept coming up: Doug Kaufman. I don't know a thing about the man, but from all of his newspaper quotes, I'm getting an impression of a real Gumby, a fellow who has one thought in his head and who bellows it out at every opportunity. If only that thought weren't wrong…
Here's Doug Kaufman in the Kansas City…
clock | January 11, 2007Continuing with the Thursday series of the BIO101 lecture notes. Check for errors of fact. Suggest improvements (June 01, 2006):
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BIO101 - Bora Zivkovic - Lecture 4, Part 1
Adaptation vs. Diversity
Biology is concerned with answering two Big Questions: how to explain the adaptation of organisms to their environments and how to explain the diversity of life on Earth.
Much of the course content so far engaged the question of the origin and evolution of adaptation, and much of the remainder of the course will also look at particular adaptations of humans…
cortex | January 10, 2007I'm curious how animal rights activists feel about this:
They are the new "Prozac Nation": cats, dogs, birds, horses and an assortment of zoo animals whose behavior has been changed, whose anxieties and fears have been quelled and whose owners' furniture has been spared by the use of antidepressants. Over the last decade, Prozac, Buspar, Amitriptyline, Clomicalm -- clomipromine that is marketed expressly for dogs -- and other drugs have been used to treat inappropriate, destructive and self-injuring behavior in animals.
It's not a big nation yet. But "over the past five years, use has gone…
tqa | January 10, 2007In Terry Pratchett's Discworld series, the universe runs on narrativium - the element that ensures that things follow the demands of the story. It's narrativium that mandates that the little old lady in the woods is a witch, narrativium that demands that a third son, attempting a task that killed two older brothers, succeed, and narrativium that ensures that the million-to-one chance succeeds 99% of the time. In The Science of Discworld 2, Pratchett and co-authors Ian Stewart and Jack Cohen point out that storytelling is a key characteristic of humans, and that it has been essential to our…
grrlscientist | January 6, 2007
I also managed to see a lot of posters today -- some of which I will tell you about below the fold (I primarily focused on those posters that discussed birds or molecular evolution of certain characters);
Albers. The mosquito larvae of the genus Ochlerotatus actively regulate of the osmotic pressure of their body fluids so as to maintain homeostasis of the body's water content, a process known as osmoregulation. For this reason, some species are restricted to freshwater habitats while others can successfully osmoregulate in saline waters that greatly exceed the concentration of seawater.…
neurontic | January 5, 2007(Information and statistics purloined from The Edge's 2007 World Question )
Violence has declined precipitously over the course of recent human history, says Chris Anderson, curator of the TED Conference. According to the 2005 Human Security Report "the number of armed conflicts in the world [has] fallen by 40% in little over a decade," as have the number of deaths per conflict. Need more convincing? Consider this: Roughly 30 percent of the male population in hunter-gatherer societies died violent deaths. "Percentage of males who died in violence in the 20th century complete with two world…
clock | January 4, 2007Tenth in the series of mini-lecture notes for the speed-class BIO101 for adults. Find errors. Suggest improvements. (May 21, 2006)
--------------------------------------------------Ecology
BIO101 - Bora Zivkovic - Lecture 3 - Part 2
Ecology is the study of relationships of organisms with one another and their environment. Organisms are organized in populations, communities, ecosystems, biomes and the biosphere.
A population of organisms is a sum of all individuals of a single species living in one area at one time.
Individuals in a population can occupy space in three basic patterns:…
mixingmemory | January 3, 2007It's a new year, and that means it's time for Edge.org's annual silly question. This year, in addition to giving the question to scientists and philosophers, they also gave it to business people, and even Brian Eno. As in the past, there are a lot of people in cognitive science and related fields on the list this year, so I thought I'd give you a brief look at how they answered the question, "What are you optimistic about?" Since this has to be the worst Edge.org question ever, and that's saying a lot, most of the answers are thoroughly uninteresting and unoriginal. You can almost feel the…
jlynch | January 1, 2007
What is this mystery beast captured on film in Kayan Mentarang National Park, East Kalimantan, Indonesia in 2003? Initial claims were that it was a new species
of carnivore. But is there evidence for this claim?
Initial discussions centered on whether the specimen was a viverrid of some kind (e.g. the very rare Hose's Palm Civet, Hemigalus [Diplogale] hosei). The WWF, who sponsored the original research, for their part felt that this was most likely a new species of civet. Recently a study by
Meijaard et al. has analyzed the two available photos of the specimen (and in so doing generated…
loom | December 29, 2006One reason I love writing about biology is that it has so many levels. Down at the molecular scale, proteins flop and twist. Higher up, cells crawl and feed and divide. They organize into animals and plants and other big organisms, which must obey their own rules in order to survive. For some organisms, a day is a lifetime. Others must weather centuries. When millions of organisms get together, they form ecosystems that wax and wane in ways that could not be predicted from lower levels. And over the course of generations, genes take on a new personality, no longer passive bits of code, but…
clock | December 28, 2006Here is the next installment of my lecture notes for teh adult education speed-class in biology. As always, I ask for corrections and suggestions for improvement (May 20, 2006):
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BIO101 - Bora Zivkovic - Lecture 3 - Part 1
Imagine that you are a zebra, grazing in the savannah. Suddenly, you smell a lion. A moment later, you hear a lion approaching and, out of the corner of your eye, you see the lion running towards you.
What happens next? You start running away, of course. How does that happen? Your brain receieved information from your sensory…
tfk | December 27, 2006A source tells the Washington Post that Uafter much pressure, the Feds will be listing the Polar Bear as a "threatened" species:
The Bush administration has decided to propose listing the polar bear as threatened under the Endangered Species Act, putting the U.S. government on record as saying that global warming could drive one of the world's most recognizable animals out of existence.
This is a remarkable step, and it is not the least bit surprising that the administration is announcing this between Christmas and New Years, when the minimum number of people read newspapers or the Federal…
clock | December 27, 2006Singing For Survival: Gibbons Scare Off Predators With 'Song':
It is well known that animals use song as a way of attracting mates, but researchers have found that gibbons have developed an unusual way of scaring off predators -- by singing to them. The primatologists at the University of St Andrews discovered that wild gibbons in Thailand have developed a unique song as a natural defence to predators. Literally singing for survival, the gibbons appear to use the song not just to warn their own group members but those in neighbouring areas.
Scanner Offers Humane Way To Look At Bird Bones:
Why…
evolvingthoughts | December 24, 2006
It's a season, so I am told, that has something to do with religion. We celebrate the birth of commodity capitalism, or something. So I thought I would combine my favourite issues - philosophy, religion and evolution.
It's all Alex Rosenberg's fault. At a dinner before the conference, he was sitting opposite me, and talk turned, as it does, to creationist attacks on science. Alex made the following claim: It is not possible to be a theist and believe in evolution by natural selection consistently.
I demurred, of course. But on further thought, I wondered if he might not be right.
To…
cmcclain | December 24, 2006
The series continues! Chris Mah and Peter's recent and wonderful posts have goaded me into next segment of the 25 Things You Should Know About The Deep Sea (the last post in this series links to all the previous). The beginnings of deep-sea science in the late 1800's was dominated by two ideas about deep-sea life, the azoic and living fossil hypotheses. The later of these was the abyss sheltered animals through previous extinction events and general catastrophes leading to a repository for fossil taxa. Louis Agassiz and T.H. Huxley, both scientific leaders of the time, were hopeful to…
razib | December 20, 2006Well, as many of you know I have been criticized quite a bit by some fellow ScienceBloggers (this query will take you where you need to go if you are a virgin to this incident). I haven't really responded for a few reasons
1) I've been very busy with week at work
2) I've been reading a great book when I've not been busy
3) I don't really see the need to address arguments which don't relate at all to what I said or intended
But, two comments piqued my interest and I feel I have to say something. They deal with my racial identity. Seeing as I'm known in some quarters as "cinnamon love, you…
cmcclain | December 20, 2006
In one of the earliest papers on the deep-sea fauna, Mosely (1880, p.593) noted, "Some animals appear to be dwarfed by deep-sea conditions." Almost a century later, Hessler (1974) noted that "individuals of certain taxa are routinely so small that they are of meiofaunal size." Thiel (1975, p. 593) echoes these comments by noting the deep sea is a "small organism habitat." Consider that the entire collection of deep-sea gastropods from the western North Atlantic collected under the WHOI's Benthic Sampling Program (44 samples, 20,561 individuals) would fit completely inside a single Busycon…