When I was a wee young lad, I remember making crystal radios and small-scale explosives for fun. The new generation can do something even cooler now, though: how about isolating your very own stem cells, using relatively simple equipment. It’s fun, easy, and educational!
Step 3, “get a placenta”, does rather gloss over some of the practical difficulties, though, and does require planning about 9 months ahead.
The vulva is one of my favorite organs. Not only is it pretty and fun to manipulate, but how it responds tells us so much about its owner. And it is just amazing how much we’re learning about it now.
Don’t worry about clicking to read more…this article is full of pictures, but it is entirely work safe because it’s all about science.
This is cool: a team using distributed computing to solve the protein folding problem has put out a promotional video asking for your unused computing cycles…and along the way they explain exactly what it is they are doing.
I mulled over some of the suggestions in my request for basic topics to cover, and I realized that there is no such thing as a simple concept in biology. Some of the ideas required a lot of background in molecular biology, others demand understanding of the philosophy of science, and what I am interested in is teetering way out at the edge of what we know, where definitions often start to break down. Sorry, I have to give up.
Seriously, though, I think that what does exist are simple treatments of complex subjects, so that is what I’m aiming for here: I talk a lot about genes, so let’s just step way back and give a useful definition of a gene. I admit right up front, though, that there are two limitations: I’m going to give a very simplified explanation that fits with a molecular genetics focus (pure geneticists define genes very differently), and I’m going to talk only about eukaryotic/metazoan genes. I tell you right now that if I asked a half dozen different biologists to help me out with this, they’d rip into it and add a thousand qualifiers, and it would never get done. So let’s plunge in and see what a simple version of a gene is.
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) 624-7389In Feburary, the Bell Museum of Natural History celebrates the birthday of pioneering naturalist Charles
Darwin with a series of discussions and films that explore his life and legacy.Thurs., Feb. 1, 7 p.m. Bell Museum Auditorium
Film — “Genius”
$7, $5 students, seniors and members
A documentary on Charles Darwin, his historic voyage to the Galapagos Islands, and his most influential work:
The Origin of Species. Highlights include expert analysis and insight into Darwin’s impact on today’s world.Thurs., Feb. 8, 7 p.m., Bell Museum Auditorium
Film — “Kansas vs. Darwin”
$7, $5 students, seniors and members
In May, 2005 the Kansas state school board held hearings that put Darwin’s theory of evolution on trial. See
for yourself what happened — and why.Tues., Feb. 13, 6 p.m., Varsity Theater, Dinkytown, Minneapolis
Discussion — Cafe Scientifique: “Understanding Evolution”
$5 Suggested Donation.
A panel of University of Minnesota researchers discusses the science of evolutionary biology, and the history
of America’s cultural response to teaching evolution. Learn about new research from professor and science
blogger PZ Myers, Bell Museum Director Scott Lanyon, and historian of biology Mark Borrello.Thurs., Feb. 15, 7 p.m., Bell Museum Auditorium
Film (Regional Premier) — “Flock of Dodos”
$7, $5 students, seniors and members
Filmmaker and evolutionary ecologist Randy Olson pokes fun at the battle between evolution and intelligent
design. He travels to his home state of Kansas to consult his mother, Muffy Moose, and confronts her
neighbor, a lawyer backing intelligent design.Tues., Feb. 20, 6:30 p.m., Bryant-Lake Bowl, 810 W. Lake St., Minneapolis
Discussion — Cafe Scientifique: “Sex, Snails & Evolution”
$5 admission. Doors open at 5:30 p.m.
Cynthia Norton, biologist and Professor of Animal Behavior at the College of St. Catherine discusses
evolutionary biology and sexual selection. Her research into the reproductive behaviors of hermaphroditic snails
is one example of the diversity of sexual behaviors found in nature. What can biologists tell us about the
evolution of sex?Thurs., Feb. 22, 7 p.m., Bell Museum Auditorium
Film — “Deepest Desires”
$7, $5 students, seniors and members
Does the difference in the way men and women approach sex have an evolutionary basis? See what happens
when a male and female actor are sent to a London university campus with hidden cameras to ask a simple
question: “Will you sleep with me?”
That clever fellow John (Chris) Walken has proposed a useful idea—that we put together simple descriptions of basic concepts in our fields of interest for the edification of any newcomers to science. He picked the magic word Clade to write about first; I don’t know why he didn’t pick “Species”, since he could have just dumped his thesis into one short, simple blog post. Maybe he’ll do that next.
Larry Moran has joined in with a lovely lucid explanation of Evolution. This is very useful, because now whenever a creationist comes along here, we can just tell him or her to go to that post and argue with Larry. If they survive that, then they are worthy of further interaction.
All of my science posts are basic and simple, so I’m not sure what I could write to add to this collection. If anyone has any suggestions, chime in and let me know.
The heathen at IIDB are talking about squid—it’s infectious, I tell you, and the godless seem especially susceptible—and in particular about this interesting paper on squid fisheries. Squid are on the rise, and are impressively numerous.
We can get an idea of the abundance of squid in the world’s ocean by considering the consumption of cephalopods (mainly squid) from just one cephalopod predator the sperm whale. Sperm whales alone are estimated to consume in excess of 100 million tonnes of cephalopods a year. This is equivalent to the total world fishery catch and probably exceeds half the total biomass of mankind on the earth (Clarke 1983). It is therefore highly likely that the standing biomass of squids within the world’s oceans probably exceeds the total weight of humankind on the earth. Given such importance squid have generally not been given the attention they deserve or have not been incorporated to the degree they need to in ecosystem models. Future research needs to rectify this.
Squid are creatures of speed: they grow fast and die young. Teleosts and cephalopods follow rather different life strategies.
The form of growth of squid is also unique and interesting. Squid just keep growing. They do not show the distinctive flattening in their growth curve shown by their fish competitors. Many species growth can be modeled with exponential or linear curves. The interesting thing is they continue growing even during their maturation phase until they die or are eaten. They seem to achieve this because of a number of unique qualities, (1) they have a protein based metabolism with efficient digestion so food is converted to growth rather than stored, (2) they are efficient feeders, using their suckered arms and beak they can remove only the highly digestible parts of prey and ‘spit out the bones’ and (3) they can grow by continually increasing the number of their muscle fibres (hyperplasia) a feature not shared by their fish counterparts. While juvenile fish recruit new muscle fibres by hyperplasia they reach a point where growth only occurs by increasing the size of existing muscle fibres (hypertrophy). This probably contributes to their flattening growth curve. Alternatively, squid show both hyperplasia and hypertrophy throughout their life span, thus they continue to recruit new fibres as well as increase the size of existing fibres (Figure 1). Such a strategy might account for their continuous growth. All of the above features contribute to the unique form of growth and the ability of squid to grow fast and fill available niches. Their life is very much life-in-the-fast-lane. They are the ‘weeds’ of the sea.
Live fast, die young…and leave a really decrepit corpse, it seems. Here’s a description of a species that really knows how to have a good time.
Much of my Southern Ocean research has focused on the warty squid Moroteuthis ingens. Up until recent years this species was poorly understood and delegated to obscurity due to lack of biological information. However, this species is regularly caught in both fishing and research trawls and my research has focused on New Zealand, The Falkland Islands and more recently Australia’s sub-Antarctic island regions. The biological understanding of this species is now perhaps the best of any sub-Antarctic squid. It is a large squid growing to over 500mm in mantle length and females achieve a much larger size than males. While M. ingens is epipelagic during its juvenile stage it undergoes an ontogentic descent to take up a demersal existence (Jackson 1993). This species has a biologically unusual and interesting reproductive strategy referred to as terminal spawning (Jackson & Mladenov 1994). Although it is a muscular squid, females (and to a lesser extent males) undergo a dramatic change associated with reproduction. Females produce a huge ovary that can reach the size of a rugby ball and weigh as much as a kilogram. In fact the ovary can weigh more than the total body weight of the male. In association with the development of the ovary the female undergoes a dramatic tissue breakdown in its body wall. This process results in a total loss of muscle fibres that transforms the muscular female into something more analogous to a jellyfish and death is associated with spawning. Moroteuthis ingens and other onychoteuthids are important prey for a number of vertebrate predators (at least four mammals, 17 birds, 13 fish, Jackson et al 1998). It is suspected that this tissue breakdown may result in dead individuals floating to the surface where they are accessible to mammals and birds.
Cool stuff…read the whole paper!
I’m teaching a course in neurobiology this term, and it’s strange how it warps my brain; suddenly I find myself reaching more and more for papers on the nervous system in my reading. It’s not about just keeping up with the subjects I have to present in lectures (although there is that, too), but also with unconsciously gravitating toward the subject in my casual reading, too.
“Unconsciously”…which brings up the question of exactly what consciousness is. One of the papers I put on the pile on my desk was on exactly that subject: Evolution of the neural basis of consciousness: a bird-mammal comparison. I finally got to sit down and read it carefully this afternoon, and although it is an interesting paper and well worth the time, it doesn’t come anywhere near answering the question implied in the title. It is a useful general review of neuroanatomical theories of consciousness—even if it left me feeling they are all full of crap—but in particular it’s an interesting comparative look at avian brain organization.
If you’ve seen BladeRunner, you know the short soliloquy at the end by one of the android replicants, Roy, as he’s about to expire from a genetically programmed early death.
“I’ve seen things you people wouldn’t believe. Attack ships on fire off the shoulder of Orion. I watched c-beams…glitter in the dark near Tanhauser Gate. All those…moments will be lost…in time, like tears…in rain. Time…to die.”
There’s an interesting idea here, that death can be an intrinsic property of our existence, a kind of internal mortality clock that is always ticking away, and eventually our time will run out and clunk, we’ll drop dead. There is a germ of truth to it; there are genetic factors that may predispose one to greater longevity, and in the nematode worm C. elegans there are known mutants that can greatly extend the lifetime of the animal under laboratory conditions.
However, in humans only about 25% of the variation in life span can be ascribed to genetic factors to any degree, and even in lab animals where variables can be greatly reduced, only 10-40% of the life span variation has a genetic component. There is a huge amount of chance involved; after all, there aren’t likely to be any genes that give you resistance to being run over by a bus. Life is like a long dice game, and while starting with a good endowment might let you keep playing for a longer time, eventually everyone craps out, and a run of bad luck can wipe out even the richest starting position rapidly.
In between these extremes of genetic predetermination and pure luck, though, a recent paper in Nature Genetics finds another possibility: factors in the organism that are not heritable, yet from an early age can be reasonably good predictors of mortality.
As we are so often reminded by proponents of Intelligent Design creationism, we contain molecular “machines” and “motors”. They don’t really explain how these motors came to be other than to foist the problem off on some invisible unspecified Designer, which is a poor way to do science—it’s more of a way to make excuses to not do science.
Evolution, on the other hand, provides a useful framework for trying to address the problem of the origin of molecular motors. We have a theory—common descent—that makes specific predictions—that there will be a nested hierarchy of differences between motors in different species. Phylogenetic analysis of variations between species allows us to reconstruct the history of a molecule with far more specificity than “Sometime between 6,000 and 4 billion years ago, a god or aliens (or aliens created by a god) conjured this molecule into existence by unknown and unknowable means”.
Richards and Cavalier-Smith (2005) have applied tested biological techniques to a specific motor molecule, myosin, and have used that information to assemble a picture of the phylogenetic history of eukaryotes.
