Biological Sex is a Big Ball of Wibbly Wobbly… Sexy Wexy… Stuff.

Categories Don’t Actually Exist

Existence does not exist in neat little categories.

We humans like our little categories because they make it easier to understand our world, but these categories only exist within our own minds.

Take, for instance, speciation. We have categories for every animal that we’ve discovered so far. But there is so much overlap. We have two egg laying mammals (the platypus and the echidna), one flying mammal (bats) and yet numerous flightless birds (penguins, ostriches, emus, kiwis, domestic fowl, et cetera),  fish that can walk on land (mudskippers), and the list goes on.

Don’t get me wrong, categories are great and all. Sorting things based on perceived patterns is a beneficial human adaptation. It allows us to understand a broader range of things because we don’t have to define everything by their own physical properties.

For instance, if I wanted to explain a crocodile to someone who’s never heard of a crocodile before, I’d likely start by saying they’re kind of like alligators.  Supposing this person is familiar with alligators, they’ll probably get an image in their head and start drawing mental comparisons. Obviously there are many notable differences between the two species, but they’re close enough to give someone a decent starting point.

If it weren’t for this human ability, we would have to start at square one with every new thing and identify them by their own unique properties in relation only to itself and as you can probably imagine, that would be awfully time consuming and would leave us with more limited time to explain to our new friend why they should probably get out of the water.

My point here is, categories are incredibly useful but there are more exceptions to the categories than there are categories.

A Brief Overview of Chromosomes

We already discussed in my previous article “‘Male’ and ‘Female’ Bodies Have the Same Blueprints” that we all started out as females in the womb, lending to many more similarity between the sexes than just nipples.

And in “Is Transsexuality a Mental Disorder?” we discussed how the genetics behind gender can get really intricate. The Y chromosome, for instance, requires the SRY gene in order to activate. Some folks lack that.

Some people are born XXY, XYY, XXYY. Some are born with a malformed chromosome.

In fact, some biologists believe that the X chromosome existed first and that the Y chromosome began as a malformed X. It is about a 3rd of the size of X chromosomes and is much more limited as far as replicating and passing on useful information.

When you think about it from an evolutionary perspective, we obviously didn’t always have X and Y chromosomes. Many other animals have different sets of sex chromosomes. For instance, birds and some reptiles have Z and W chromosomes, which behave contrary to our XX/XY system. Females are typically ZW and males are typically ZZ.

This gets even weirder when we consider transitional examples between the two apparently different systems. For instance, the southern platyfish has both XX/XY and ZZ/ZW sex determination systems often within the same populations.

This tells us that XY and ZW systems have common origins and transitioned at some point into two separate systems, possibly via fish. Neat!

The platypus is another oddity (I mean aside from the obvious). Instead of a pair of sex determining chromosomes, the platypus has ten. TEN! Five of these behave like the mammalian XX/XY system, while the other five behave more similarly to the avian ZZ/ZW system.

Various other sex chromosomal systems exist, and as we’ve seen, the systems sometimes overlap, and there exist numerous exceptions in any sex determining system.

Considering that our very distant ancestors were single-celled, the lineage of our XX/XY system goes back to asexual roots. It’s not rocket science.

Sex Is Non-Linear

To firmly grasp gender, it helps to think about it as the eventual result of numerous conflicting processes. Some processes contribute masculine traits, while others contribute feminine traits.

So, for instance, one could have XY chromosomes with a normal functioning SRY gene attached to the Y and produce a LOT of manly testosterone. Yet that same person could also have really long androgen receptors but shortened estrogen receptors (or simply more of them), thus decreasing androgen potency and making estrogen much more easily metabolized.

So you can see it’s not exactly straightforward. This is why gender is so obviously a spectrum. Speaking of gender in binary terms doesn’t truly make sense scientifically no matter how you try to spin it.

The fact of the matter is that biological sex is a big ball of wibbly wobbly… sexy wexy… stuff.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s