Indicators of Genetic Quality in Males and Females

It's sad but true guys: in this culture of equal opportunities and 'Love Thy Body' articles in magazines, we still cannot escape our evolutionary past.
Several studies have shown that there are Sexual Dimorphisms (differences in the form and function of males and females- e.g. the colouration of male and female ducks, or size difference between male and female gorillas) that we assume to be neutral in our culture, that actually show how good our genes are to our mates.

Firstly, male facial structure is influenced by testosterone, a sex hormone that is also an immunosuppressant. More masculine faces (deep set square jaw, more prominent brow ridges) use more of this hormone to produce, so the theory goes that they must have fantastic genes to be able to offset this physiological burden, and so they are snapped up by the women.

Secondly, is the issue of breast size. While there is no correlation between breast size and milk quality or quantity, that sneaky sexual selection comes back to bite us on the.. well, breast. This theory is that larger breasts, taking more oestrogen to produce, are the costly signal of higher genetic quality to rival that of the men's. It's unfortunate but true, that bigger boobs can mean you have better genes.
But before you start thinking of that enormous woman down the road who has breasts down to her knees, it's also the symmetry of the breasts that is important, indicating that we survived puberty with little disruptance to our development, also making us fabulous genetic contributors.

Now we all know that it is perfectly normal to have one boob slightly bigger than the other, and our boobs really give us no advantage or disadvantage in today's world. So don't go thinking that because your boobs are a bit wonky you're not as good as other people, as there are many more factors that go into choosing our perfect partners today, and I bet your boyfriend has never had any complaints!

A Little Something To Keep In Mind...

A lot of men don't understand the truth to the statement that a women takes a lot more work than they do to get going.
It may seem like your woman is being selfish or just delaying the main event, but it really does take a lot for a woman to become fully aroused.
There are so many benefits to waiting until this point though, physical benefits like the vaginal muscles relax, natural lubrication flows and makes the whole experience much more relaxed, as well as it leading to fewer problems like UTIs and bruising.

So women, next time your man doesn't understand this fact, show him this picture, it was designed for a reason!

While the Cat's Away...

There are several interesting phenomena that can be observed in the case of a couple that spends a lot of time apart.

-> Even if a man masturbates that morning, his sperm count will still be higher than normal upon reuniting with his partner.

-> When the couple is reunited, the man will thrust deeper and faster when they have sex.

These are adaptive mechanisms that date back to prehistoric times, that would have ensured that, had the woman been having sex with another man, her usual partner could still assure his paternity of any future offspring. This is basically saying that the man wants to make sure he's the only possible father of any kiddies the woman may have.

Penis Facts

Next, here are some little-known penis facts! All taken from my lecture by the lovely Dr Sarah Johns.

1- Richard Dawkins noted that the boneless human penis is a sexually selected trait. As most primates have a bone at the base of their penis, the fact that humans don’t is a way of an individual showing how fit he is as he doesn’t need a bone to maintain a hard erection

2-Where females mate with multiple males, it leads to fancy penis morphology. Where females are more monogamous, penis morphology tends to be simpler

3- Humans’ glans is exaggerated and has a coronal ridge, which is thought to function as a semen scoop- scooping out the previous male's sperm

4-Testes size is correlated with the level of polygyny in the mating system, not just body size. Human teste size indicates a limited degree of polygyny is likely to have been typical of our recent ancestors

5-Production of sperm cannot occur at the body temperature of most mammals. Testes are therefore held outside the abdominal cavity, where the temperature is lower

Sperm Facts

Here is a selection of interesting Sperm Facts to kick off this blog:

1- Each ejaculation contains 2-5ml of semen

2- This ejaculation will contain around 300 million sperm. Only ONE of which (the best one!) will fertilize an egg

3- Only 1% of ejaculate is sperm. The rest is made up of fluids that counteract vaginal acidity to give the sperm the best chance to reach the egg.

4- It is theorized that defective sperm, such as those with two tails, are included in semen in order to block out any remaining sperm from other men reaching the egg

5- The last few drops of ejaculate have spermicidal properties, to form a barrier between that sperm and any later man’s

6- When a couple has been separate for a while, even if the man masturbated that morning, the ejaculate amount will still be large

Welcome to Chemistry or Biology!

Hi there!
My name is Cally and I'm a second year Anthropology student.
My modules have a biological slant, and one in particular by the name of Sex, Evolution and Human Nature has caught my eye. The lecturer is a genius, and she's hilarious too, which is always good for us students with a short attention span!

Since I was at middle school, I've always had excellent sex education classes, which unfortunately is not the norm for pupils across the world. I believe this is truly a matter of priority, as it is what the future of our world's population hinges on.
Some of my key interests include sexual health and contraception issues, and I feel very strongly against teenage pregnancy (no disrespect- I know kids are what some girls have always dreamt of) and against unwanted pregnancy in general.
In my opinion, there's no reason why someone couldn't get an abortion, but preventing an unwanted pregnancy is always better than cure.
In this blog I will be posting interesting facts I learn in my lectures and on my travels through the internet, clear and concise contraception advice and other bits of information you really should have already been taught.
I hope you enjoy this blog, always feel free to comment on any posts with any questions you might have.
Cally