Life Sciences
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I 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…
Giraffine giraffes (that is, the giraffid clade that includes Giraffa and its closest relatives) are famous for being long necked, with the usual explanation for the neck being that it evolved to enable these animals to avoid competing with other browsers.
But for this assumption to be experimentally supported you'd have to show that giraffes use their long necks to forage high up, and show that giraffes have a competitive advantage over shorter browsers. Surprisingly, it has been argued that these assumptions don't hold up. In some areas, over 50% of all giraffe browsing is done below 2 m…
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Next in the series of BIO101 lecture notes. Chime in to correct errors and make it better (reposted from June 11, 2006):
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Anatomy is the subdiscipline of biology that studies the structure of the body. It describes (and labels in Latin) the morphology of the body: shape, size, color and position of various body parts, with particular attention to the internal organs, as visible by the naked eye. Histology is a subset of anatomy that describes what can be seen only under the misroscope: how cells are organized into tissues and tissues…
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Nonvenomous Asian Snakes 'Borrow' Defensive Poison From Toxic Toads:
Most snakes are born with poisonous bites they use for defense. But what can non-poisonous snakes do to ward off predators? What if they could borrow a dose of poison by eating toxic toads, then recycling the toxins? That's exactly what happens in the relationship between an Asian snake and a species of toad, according to a team of researchers funded by the National Science Foundation (NSF) Division of Integrative Organismal Systems (IOS).
More....
To Trust Or Not To Trust Your Friends:
Sometimes it is better to follow the…
In the latest installment in that 'evolution of vampires' thread, we learn how a chronic decline in populations of the Yellowbilled oxpecker has highlighted the pretty obvious fact that not all oxpeckers are alike. Why didn't I mention this sooner: d'oh!
Before I got distracted by troodontids, owls, godwits, or sloths, I was talking about oxpeckers and the evolution of blood-feeding and vampirism. Here I'll start the beginning of the end of this thread: we'll go via blood-feeding passerines to bats, and then finish with pterosaurs. It's likely, of course, that I'll get distracted before I…
Sloths. Were there predatory sloths? Sloths that lived in the sea? Sloths that dug immense tunnels? Sloths on Antarctica? Sloths so keen to get to the US of A that they didn't wait for the land bridge, but swam the way instead? Well, let's see...
Today I was asked a question about sloths. Sloths are among my favourite mammals, and hence I feel particularly guilty in not having blogged about them, though I did publish a review article on them fairly recently (Naish 2005). Not only does this distraction allow me to delay yet further those promised posts on blood-feeding birds and bats,…
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As always, see how well the press release matches the actual paper:
Distinct Bison Herds Roam Yellowstone:
So what's the scoop on bison poop? First, Gardipee has found a gentle, noninvasive way to study the DNA of the animals in the park. Secondly, the genetic material she and her team extracted suggests the roughly 4,000 bison in Yellowstone are divided into at least two distinct breeding groups, which could have implications for how they are managed.
Genes May Tell A Lot About The Secret Lives Of Bees:
Despite the fact that bees are one of the most beneficial insects in the world, much of…
Ok.. so perhaps it's not a total museum dedicated to homosexual animals - but it looks like a pretty good sized exhibit. Unless you're in Norway you might be missing the exhibit though. Anyone want to sneak some photos for us?
From male killer whales that ride the dorsal fin of another male to female bonobos that rub their genitals together, the animal kingdom tolerates all kinds of lifestyles.
A first-ever museum display, "Against Nature?," which opened last month at the University of Oslo's Natural History Museum in Norway, presents 51 species of animals exhibiting homosexuality.
Here'…
tsmith |
Like most fields, microbiology is one filled with jargon. Many laymen don't even realize the differences between a bacterium and a virus, much less the smaller differences between, for example, a pathogenic versus a commensal organism. So, while I haven't decided yet exactly what I might write about in future posts, I thought I'd begin with a very general microbiology primer to get everyone up to speed on the basics of the microbial word.
To begin with, in the "well, duh" category, microbiology is the study of very tiny life. Initially, those studied were mainly disease-causing organisms;…
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The latest re-post of my BIO101 lecture notes (this one originally from June 05, 2006). I know I will have to rewrite everything about the Three Domain Hypothesis, but you also tell me if I got other stuff wrong or if this can be in some way improved for the classroom use.
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BIO101 - Bora Zivkovic - Lecture 4, Part 3
In the first two parts of this lecture we tackled the Origin of Life and Biological Diversity and the mechanisms of the Evolution of Biological Diversity. Now, we'll take a look at what those mechanisms have produced so far - the…
From the Improbable Research blog and Reuters:
BEIJING, China (Reuters) -- Hundreds of chickens have been found dead in east China -- and a court has ruled that the cause of death was the screaming of a four-year-old boy who in turn had been scared by a barking dog, state media reported on Wednesday.
The bizarre sequence events began when the boy arrived at a village home in the eastern province of Jiangsu in the summer with his father who was delivering bottles of gas, the Nanjing Morning Post reported.
A villager was quoted as saying the little boy bent over the henhouse window, screaming…
More on oxpeckers, on wound-feeding, and on the delightful habit of eating earwax...
In the previous post we looked at the behaviour of oxpeckers: the idea that they feed on blood and the other tissues of their hosts was introduced, and we can now doubt the idea that they are always symbiotic 'friends' of the mammals they clamber about on. As demonstrated by Paul Weeks in his several studies of the birds (Weeks 1999, 2000), oxpeckers spend a considerable amount of foraging time feeding - not on ticks - but on blood, ear wax, and on dead skin that they 'scissor' out of the fur. We also saw…
Species: A term which everybody thinks they understand, but which nobody agrees upon, to denote the "basic units" of groups of biological organisms.
It is sometimes said, or has been said to me, that one ought not know too much about a topic if you are to define it clearly. This is because the expert knows all the many nuances that apply in different conditions, and writes not to the beginner but to the other experts. So I must note here that my thesis and continuing work is on species concepts, and things may get a bit rocky. You've been warned.
First of all I'd like to disagree with…
razib |
Many fellow ScienceBloggers are doing a "Basic Concepts" series. Here are some of them:
Mean, Median, and Mode
Normal Distribution
Force
Gene
Central Dogma of Molecular Biology
Evolution
Clade
Instead of thinking up something new I've decided to repost a an older post where I cover the "basic" equations and models which I pretty much assume in many of my posts. The post below....
Begin repost
Occasionally I appeal to formalizations or equations on this weblog to illustrate a general verbal principle. I don't do it to obscure or needlessly technicalize a topic of interest, but rather, it is…
Not Darwin. Not Lamarck. Not the Greeks. A French physicist and mathematician...
Pierre-Louis Moreau de Maupertuis (1678-1759) was an interesting man. He devised what we now know as the principle of least action, and showed that the earth was flattened. Some other things he did, however, changed biology forever.
In 1735, the first edition of Linnaeus' Systema Naturae was published. Linneaus put out at least 13 editions of this in his lifetime, and the famous 10th edition was adopted in the 19th century as the "gold standard" - if Linnaeus named a species, that was its name thereafter…
Sleeping flamingos, Phoenicopterus ruber.
Orphaned image, please contact me for proper credit.
People Hurting Birds
Avian pathologists have determined that the deaths of 63 birds in downtown Austin, Texas, this month were the result of natural causes. Texas A&M University pathologists examined nine of the birds found dead on 8 January and determined they died because of parasites and a drop in temperature, the Austin American-Statesman reported Friday. "These birds were heavily parasitized by multiple species of parasites," said Lelve Gayle, the executive director of the Texas…
Bioethics is an important subject—it's too bad it gets sidetracked with nonsense driven by religious dogma and ignorance. One issue is the use of human-animal chimerae in research, which was enough to get our flibbertigibbet idiot of a president incensed, but I don't see the problem. It's not as if having weirdly modified experimental mammalian embryos in a dish is a danger to people—some devout Christian woman does not have to worry that she might bump into a lab cart and have a swine-man zygote splash into her vagina and crawl into her womb, but that's exactly what the hysterics seem to…
More psychic pets! Wooo... aren't you excited? I uhh... am?
by Craig Hamilton-Parker
Does your pet read your mind, see into the future, know the time or can find you wherever you are? Professional TV psychic, Craig Hamilton-Parker, believes many pets have psychic powers. Here he reveals the evidence and has designed some simple experiments to test your pet's paranormal potential.
Hmm... It's almost like he's one of those people who calls himself by his own name... weird. But not quite as weird as
the whole pet psychic idea to begin with.
Scientific research is slowly beginning to…
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Part 12 of my BIO101 lecture notes. As always, click on the web-spider icon to see the original post (from June 04, 2006). Correct errors and make suggestions to make this better. Perhaps this entire series can be included in the "Basic Concepts" series.
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BIO101 - Bora Zivkovic - Lecture 4, Part 2
In the previous segment of the lecture, we looked at the Origin of Life and the beginnings of the evolution of biological diversity. Now we move to explanations of the mechanisms by which diversity arises.
Although traits can be inherited by non-DNA…
The Bell Museum in Minneapolis is pulling out all the stops in the month of February, celebrating Darwin's birth month with an orgy of science and sex. I'm going to be there for the events on the 13th and 15th, and I'm really tempted by the talk on the 20th—I'll have to see if I can get away for that one.
People in Minneapolis/St Paul ought to appreciate that this kind of public outreach is what good museums do, and take advantage of the opportunities!
Bell Museum of Natural History, University of Minnesota
10 Church St. S.E. , Minneapolis, MN 55455, (612) 624-7389
In Feburary, the Bell…