Male antelope scares female into staying for sex

During mating season, male topi antelope trick females with false alarms of nearby danger to boost chances for sex, a new study says. If a female starts wandering out of a male's territory, the male will begin snorting and staring, ears pricked, at nonexistent predators."The female will be walking away, and the male runs in front, looks not at the female but where she's going, makes this snort, and she typically stops," said lead researcher Jakob Bro-Jørgensen of the University of Liverpool.

The paper is in The American Naturalist (Male Topi Antelopes Alarm Snort Deceptively to Retain Females for Mating) and there's a news report at the National Geographic site.

Sharks can become invisible?!

So this isn't exactly related to what we are learning in class right now, but I had to post. Up to 10% of sharks are "luminous" - they emit light from organs called photophores. This creates an optical illusion making them invisible to predators and prey! It also turns on sharks of the opposite sex. Pretty crazy.

Here's the link to the article:

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T8F-4YWBJSM-1&_user=112642&_coverDate=05%2F31%2F2010&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1347934181&_rerunOrigin=scholar.google&_acct=C000059608&_version=1&_urlVersion=0&_userid=112642&md5=66e2f1a151994981804dffb1694ab4c9

Smells like Teen Spirit, or maybe lilac....

Did you know that the 2004 Nobel Prize was awarded to Richard Axel and Linda B. Buck for their discoveries of "odorant receptors and the organization of the olfactory system"?

There's a nice summary of their research on the Nobel website (this is the summary of the summary - check the link for the full version):

The sense of smell long remained the most enigmatic of our senses. The basic principles for recognizing and remembering about 10,000 different odours were not understood. This year's Nobel Laureates in Physiology or Medicine have solved this problem and in a series of pioneering studies clarified how our olfactory system works. They discovered a large gene family, comprised of some 1,000 different genes (three per cent of our genes) that give rise to an equivalent number of olfactory receptor types. These receptors are located on the olfactory receptor cells, which occupy a small area in the upper part of the nasal epithelium and detect the inhaled odorant molecules.

Each olfactory receptor cell possesses only one type of odorant receptor, and each receptor can detect a limited number of odorant substances. Our olfactory receptor cells are therefore highly specialized for a few odours. The cells send thin nerve processes directly to distinct micro domains, glomeruli, in the olfactory bulb, the primary olfactory area of the brain. Receptor cells carrying the same type of receptor send their nerve processes to the same glomerulus. From these micro domains in the olfactory bulb the information is relayed further to other parts of the brain, where the information from several olfactory receptors is combined, forming a pattern. Therefore, we can consciously experience the smell of a lilac flower in the spring and recall this olfactory memory at other times.

Phagocytosis

This video, taken from a 16-mm movie made in the 1950s by the late David Rogers at Vanderbilt University, shows a neutrophil chasing down and consuming bacteria. Although some or all of the movement of the bacteria may simply be due to Brownian motion the movement of the neutrophil is clearly directed, in this case by chemical gradients. There's another nice video showing neutrophil chemotaxis here.

Unfortunately internet memes run a strong and I immediately thought of the following BoingBoing post - Adding the Benny Hill Theme to Anything Makes it Funny. So it was no surprise to find someone had already done that.

A moift and wet foil

You have probably all used JSTOR at one time or another to get access to online journals. What you might not realize is that JSTOR is part of ITHAKA, a not-for-profit organization helping the academic community use digital technologies to preserve the scholarly record and to advance research and teaching in sustainable ways.

JSTOR is currently collaborating with The Royal Society to digitize, preserve, and extend access to their Philosophical Transactions back to 1685. So, for example, you can now read the first journal report on the medicinal powers of willow bark (now known to be due to high concentrations of salicyclic acid - closely related to the active ingredient in aspirin.) Salicyclic acid is now known to be an important compound in mediating what is known as 'systemic acquired resistance' in plants - the plant equivalent to the innate immune system found in animals.

At this time in human history the 'doctrine of signatures' was still widely believed - that a plant shaped like a body part or disease would be useful in curing it (hence the names liverwort, woundwort, toothwort, wormwood etc). This was a theological reasoning rather than a scientific observation - it was reasoned that the Almighty must have set his sign upon the various means of curing disease which he provided. Through time this concept was expanded so that the "signature" could also be identified in the environments or specific sites in which plants grew.

Hence the following passage:

'As this tree delights in a moift and wet foil, where agues chiefly abound, the general maxim, that many natural remedies carry their cure along with them, or their remedies lie not far from their caufes, was fo very appofite to this particular cafe, that I could not help applying it; and that this might be the intention of Providence, I muft own had fome little weight with me.'

Undergraduate Research Colloquium

This Thursday, 20th May, is the UCSB Undergraduate Research Colloquium - A poster exhibition that recognizes the scholarly achievements of students and acknowledges the faculty who have contributed to the development of student research and creative projects.

It is held from 11:30 a.m. to 2:00 p.m in the Corwin Pavillion - so it is very convenient for you to wander across after class and take a look around. This is usually quite a large event with over a hundred posters.

Don't forget Brad Hawkins talk today at 4pm (see below).

Golden Years Truly Are Golden

As I mentioned in class the AAAS website reported on a PNAS paper out online yesterday: A snapshot of the age distribution of psychological well-being in the United States

In contrast to other, similar, studies this one used a large sample with fewer questions. In fact the sample size was over a third of a million people!

Stone's team found that global well-being declines from the 20s to age 50, then increases steadily. Happiness and enjoyment also increase after age 50. Although sadness is fairly flat throughout the age groups, most negative feelings decline with age. Worry stays level until about 50, then drops. Anger falls steadily from the 20s; stress peaks in the 20s, starts a decline, then plummets after age 50. The patterns are almost identical for men and women, although women have more stress, worry more, and are sadder at all ages, despite reporting better global well-being than men at most ages. The findings make sense to anyone who has gotten out of their 20s, says Stone. "If you were to do a survey and say, 'How many of you would like to be 25 again?' you don't get a lot of takers," he says.

Hopefully this news is not too depressing to those of you looking at 25 from the other side!