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Today (February 5th) is “National Wear Red Day” yet another phlegmatic pseudo-holiday in the short-yet-ever-so-long month of February. However there is a great fundamental truth buried in National Wear Red Day. Aside from working out day and night or becoming a multi-millionaire celebrity, wearing red is one of the few things you can do to make yourself more attractive to potential mates (I am just assuming that you are a classical human being–if you are a futuristic cyborg, or an alien lifeform, or a super-intelligent animal of some other sort, please, please, please leave a comment, even if its a thousand years from when I write this).

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I am somewhat foreshadowing next week’s theme, but primates are the most colorful mammals. For monkeys and apes and hominids, colors carry all sorts of highly-charged hierarchical, social, and physiological messages. At a conscious level, we may be only dimly aware of these signifiers, but they apparently come through loud and clear to our endocrine systems. Administrators at dating sites report a 6% boost of positive replies to people wearing red in their profile pictures. Scientists and psychologists have found similar results in experiments which query men and women about the attractiveness of photographs of people of the opposite gender.

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The power of wearing red extends beyond the bedroom to the business and sports realms. Teams that have red uniforms have been demonstrated to have greater likelihood of victory (although I shudder to imagine how statisticians figured that out). The power of the not-very-imaginatively-named “power tie” is well known (at least anecdotally). Even in battle, red seems to have once conferred an advantage. The troops of great empires have had a way of wearing red garb (although, admittedly, advances in gunnery and tactics seem to have greatly negated–or reversed this trend). The Roman legions wore red. The British redcoats uh, wore red. The Chinese super-lucky national color is red. Kelly Lebrock wore red. So ignore how stupid it sounds. Shrug off your inhibitions (and your national reticence to take orders from a day of the month) and wear red.

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Unless You are Steve Seagal

Regular readers know how much I esteem turkeys.  Unfortunately I worry that my writings are not winning additional admirers for these astonishing birds.  It is time to play a trump card and reveal one of the great bizarre strengths of turkeys.  They are capable of virgin birth.

A New Mexico Whiptail (Aspidoscelis neomexicana). All New Mexico Whiptails are female. The entire species reproduces by parthenogenesis.

Before you spring up in alarm and start shouting, allow me to present a miniature biology lesson. Parthenogenesis is a form of asexual reproduction. Some female organisms are capable of producing an ovum which develops into a new individual without being fertilized by a male gamete.  In these cases, the mother contributes her genetic material to the offspring.  Although natural parthenogenesis is frequently observed in rotifers, insects, mollusks, crustaceans, and flatworms, this method of reproduction is much less common among vertebrates. However a few species of fish, amphibians, and reptiles are known to reproduce via parthenogenesis (movie-goers may recall that this happened to the dinosaurs in Jurassic Park.)  The turkey is very unusual in being a bird which can reproduce through this means (or at least we think it is unusual—perhaps parthenogenesis is more common among birds then we realize but we just don’t know about it except in settings like farms where it becomes obvious). Chickens can also produce self-fertilized eggs but they almost never develop beyond embryonic stages, whereas female turkeys can and frequently do produce living offspring which lack fathers.

This diagram from the BBC actually explains shark parthenogenesis but you get the idea.

Parthenogenesis occurs in turkeys through the doubling of haploid cells.  Biologists have discovered that the rate at which this occurs can be increased by selective breeding. Poults produced by parthenogenesis are capable of growing into healthy viable toms indistinguishable from toms with more traditional parentage.  You will note that I wrote “toms”—all turkeys conceived via parthenogenesis were created from doubled haploids and are are homogametic. Consequently they are all all male. (This will leave mammal enthusiasts scratching their heads–since female mammals are homogametic and have two x chromosomes. However for birds and for some reptiles, males have two Z chromosomes and thus are the homogametic sex. In such species, females have one Z and one W chromosome and are the heterogametic sex.)

Mammals do not naturally utilize parthenogenesis as a method of reproduction. Certain portions of mammalian genes consist of imprinted regions where portions of genetic data from one parent or the other are inactivated. Mammals born of parthenogenesis must therefore overcome the developmental abnormalities caused by having two sets of maternally imprinted genes.  In normal circumstances this is impossible and embryos created by parthenogenesis are spontaneously rejected from the womb. Biology researchers have now found ways to surmount such obstacles and a fatherless female mouse was successfully created in Tokyo in 2004. With genetic tinkering, human parthenogenesis is also biologically feasible. Before his research was discredited and he was dismissed from his position, the South Korean (mad?) scientist Hwang Woo-Suk unknowingly created human embryos via parthenogenesis. To quote a news article by Chris Williams, “In the course of research, which culminated with false claims that stem cells had been extracted from a cloned human embryo, Hwang’s team succeeded in extracting cells from eggs that had undergone parthenogenesis… The ability to extract embryonic stem cells produced by parthenogenesis means they will be genetically identical to the egg donor. The upshot is a supply of therapeutic cells for women which won’t be rejected by their immune system, without the need for cloning.”

All of which is fascinating to biology researchers (and those who would seek greatly prolonged life via biogenetic technologies), however it seems that in nature, the turkey is the most complicated creature capable of virgin birth.

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