Hi everyone, I hope you'll forgive my slight detour from the topic at hand--medical problems and the medical world--for me to show you some of the really cool work I had the pleasure to research as part of my AP Biology class this year. (It's an awesome class and if you're still in high school, think about taking it!) This is a summary of a research article I had the fortune of reading a couple of months ago, and it pertains to sexual attraction in animals and how that relates to pigment.

In many species of animals, females will prefer males who have more physical ornamentation-for example, female peacocks prefer male peacocks with more elaborate and colorful feathers. It is widely debated how and why this is.

Carotenoids are pigments responsible for the production of red and yellow colors in an individual's phenotype. They are acquired through food and provide antioxidants and boost immune system. It is hypothesized that males in better condition don't need as many carotenoids, so that when they do consume them it serves to physically display their fitness in the form of richer pigmentations. To test whether females preferred males with higher carotenoid levels in their bodies, and whether more fit males were more able to procure carotenoid-­‐rich foods, the authors of this study conducted an experiment with zebra finches.

The finches were 10 fully-­‐grown brothers, some of who received a control of plain water, and others of who received water containing carotenoids, every day for 8 weeks. All the finches were fed white millet, and any other possible factors were controlled. In zebra finches, bill color is affected by carotenoids, so the researchers created a scale of color from 1-­‐9 (light orange to dark red.) The brothers were relatively similar in beak color, and those who were given carotenoid supplements ended up with much redder bills than those who were given the control.

After 6 weeks of the diets, the researchers observed how much time female zebra finches spent next to the male zebra finches from the experiment. They used this data to measure how attractive the females finches found the males, and concluded that the females preferred males with more red bills, and those with higher display rates.

After roughly another 2 weeks, the researchers collected blood samples from the finches to observe plasma carotenoid levels. Later, they injected PHA (phytohemagglutinin), a lectin which induces immune response, and is therefore an antigen, into the wing webs of the same birds. The zebra finches with the carotenoid supplements had more circulating carotenoids in their systems and had more exaggerated responses to the PHA injections. (sidenote: studies suggest that birds which have bigger responses to PHA are generally more fit.)

One can infer from this study that different levels of carotenoids can cause variation in sexual attractiveness and the ability of the immune system to function. Furthermore, there is a hypothesis that females who mate with males who have higher levels of carotenoids may be less likely to contract diseases, and more likely to receive parental support from their mates if necessary. It has even been suggested that offspring of such males could be born with advantageous traits, even though no evidence has been provided that diet-­‐related carotenoid levels are severely affected by genetic factors.

It is questionable whether obtainment of carotenoids can reflect on an individual's traits, such as energy and ability to effectively forage. However, the research on the zebra finches effectively depicts the correlation between carotenoid levels in an individual and the efficacy of their immune system.

Hi All,

In the light of Valentine's Day having just recently passed, I gave some thought to the idea of love and how it could relate to health, medicine, and this blog. While most people think love is a great thing--and it definitely is--I recently found out from a discussion with my mother that obsessive love can become a genuine clinical disorder. Take, for example, "erotomania." To talk about the meaning of the word, "eroto" as a root refers to some type of sexual desire, while "mania" indicated obsession; and that is exactly what erotomania is, not surprisingly. Erotomania is a genuine delusion that one may have that someone who is somehow more socially important than they are will or is falling in love with them. In 2002 a research group conducted a study which came to the conclusion that, of the subjects which they observed for erotomania, 11 were women while only 4 were men. There were certain characteristics associated with people afflicted with this condition; they tended to not have a steady job, or be particularly close with many other people. A very high percentage--40%, to be exact--were directly related to someone with a psychiatric issue; however, interestingly enough, less than half of them appeared to have subjected their love interest to any form of "harassment." This disorder, while it may seem somewhat grave, is apparently easily treated and helped. While it does not seem to react well to treatment with actual medicines, cognitive behavioral therapy (therapy capitalizing on the malleability of the mind and a person's ability to change perspective) seemed to affect change in patients. I thought this disorder was particularly interesting because it never occured to me that a person could have a legitimate clinical obsession with another person. Talk about crazy in love!

http://www.ncbi.nlm.nih.gov/pubmed/11788912. Erotomania Revisited: Clinical Course and Treatment. Kennedy N, McDonough M, Kelly B, Berrios GE. 2002.