sex – BioQuakes

All Organs are Sexual!

On February 29, 2016

Well, in the sense that female non-sexual organs and male non-sexual organs aren’t the same, as they’ve been commonly considered to be. According to a team at the MRC Clinical Sciences Centre (CSC), at Imperial College London, the stem cells that make up your organs do have a sexual identity attached to them, and thus behave differently than their sexual counterparts. In this study, a female fruit fly’s gut was observed to have enlarged after mating, likely due to the increased nutritional intake to rear healthy offspring. The reason this isn’t done all the time is that this makes it more likely for tumors to develop in the gut, so this is only done when the sake of their progeny is at stake.

(This fruit fly may be female, but her intestines were made to identify as male. There’s potentially some conflicted gender identity.)

What’s interesting is that when the female fruit fly was given male gut stem cells, the gut no longer enlarged after mating, and retained the smaller gut size of males. It turns out that the sex organs are not the only organs that have a sexual identity. At least, in fruit flies. No tests have been done on human organs yet, although it is believed that the principle will hold true, albeit in potentially different ways.

(Artist rendition of stem cells)

Medically this is significant since it may lead to explanations or understandings of how and why male and female patients may need different medical treatments since their organs function somewhat differently. Furthermore, it continues to advance our understanding of how males and females are different based on the nuances of the physical workings of their body. Overall, it’s very confusing when you apply this to gender theory.

But humans have had a poor understanding of their own bodies and inner workings for thousands of years. Is it possible that this is on the path to a deeper understanding of our physiology as a gendered species, or that these differences are conditional and minute, as I so far believe?

New Species Discovered in a Famously Sexual Animal Family

By Thans

On February 27, 2014

In Student Post

The Antechinus family of rodents has one of the most peculiar sex lives in the animal kingdom, and just recently another species was discovered. These small dasyurid marsupial are carnivores who live in Australia and New Guinea. The most extraordinary aspect of the Antechinus family is their sexual cycle. Most males live only long enough to breed, being born in November and reaching sexual maturity around August of the following year. By the time the males are old enough, they cease to function except for the sole purpose of finding a mate. The shrews stop eating and sleeping and begin to shut down bodily functions deemed ‘unnecessary’ so as to save energy for finding a mate and passing on genetic material. This ‘sacrifice’ of bodily functions goes so far as to shut down the immune system and strips the body of vital proteins. As a result of these sacrifices, the males do not long outlive their first sexual experience, which can last about 12 hours. The females live slightly longer, lasting the entire mating season and storing all of the semen within their bodies until ovulation at the end of the season, producing liters with children from various fathers. Although some females manage to survive up to 3 seasons, most die after their first litter.

A relative of the new species from the genus Antechinus

The new species, the black-tailed antechinus, was previously thought to be part of the dusky antechinuses species which is significant in that males are larger and commonly live for multiple mating seasons. It is unknown at this point whether the black-tailed antechinus shares that advantage or if the males simply die after their first season like most of the members of their genus. Other than their peculiar mating habits, the fact that a previously unknown species was discovered in Australia is remarkable, because new mammal species are extremely rare. However finds such as this of new species demonstrate how many new and interesting species of mammals and other organisms may still be out there.

Dear Darwin: What Makes Ryan Reynolds “Sexy”?

By gambibambi

On October 17, 2011

In Student Post

Photo Credit: Paco Paco Flickr

Now we all know that a big jaw, prominent brow, and bulging muscles are conventionally thought of as attractive features in a man and that large breasts, an hour-glass figure, and big eyes are attractive in women, but have you ever wondered why?

Well the answer lies in an unexpected place: science. According to the Evolutionary Theory of Attraction, what men and women perceive to be attractive is actually based on adaptational behaviors that traditionally helped survival. Studies show that women look for masculine features such as a defined jaw, prominent brow, and muscular build because these often to reflect physiological and behavioral traits such as strength, aggression, virility, and a strong immune system, which would be advantageous to pass on to offspring and would mean that the man can provide and protect his family.

So while women’s attraction is rooted in a man’s ability to provide for his family, men on the put more emphasis on signs of fertility and youth. The hour-glass figure: large breasts and “child-bearing” hips, and youthful features such as plump lips, a hip-to-waist ratio of 0.7, a face with a high forehead, good skin, and big eyes are signs to men that the prospective mate is fertile and young. Such features helped ensure the male that his genes would be passed on to his offspring. Other factors such as symmetry, especially facial symmetry, is attractive because it means that there are strong genetics at work according to researchers and experts.

Recent studies show that when a woman chooses a mate, often times she must subconsciously choose between a macho man and his more wimpy counterpart depending on her situation. While the macho man has preferential genes to pass on to offspring, these traits often mean tendency to abandon, hostility, and promiscuity. The less masculine man is more likely to provide the stability, love, and care for a family. In fact, according to expert, Dr. DeBruine’s study, a woman’s environment greatly plays into her attraction between these two types of men. In her study on women in countries with poor health standards, women preferred men with more masculine features more than those who lived in more stable and healthy societies. This is a classic example of natural selection because the women look for healthier genes often associated with masculine, macho attractive men.

So that is why we find movie stars like Angelina Jolie, Brad Bitt, and Ryan Reynolds are attractive: evolutionary adaptations meant to help ensure our survival and the successful passing on of genes to offspring. Do you agree with this theory of attraction? And which category would you put yourselves in ladies, those who go after Mr. Sensitive or those who go after Mr. Dangerous?

For more on this go to:

http://www.cnn.com/HEALTH/blogs/paging.dr.gupta/2007/10/evolution-of-attraction.html

http://ezinearticles.com/?Male-Female-Attraction—Evolutionary-Theory&id=2236366

http://wilderdom.com/personality/L7-2EvolutionPersonality.html

http://www.economist.com/node/17672806

http://antimisandry.com/chit-chat-main/sociobiological-theories-attraction-11277.html

http://webspace.ship.edu/cgboer/sociobiology.html