As the old saying goes, men are from Mars, women from Venus (Picture: Getty Images/iStockphoto)

Men: for women, they are perhaps the world’s greatest mystery until they end up dating one.

Sure, there’s sex education enough to know how the basics work, but it’s not until you’re up close and personal with a guy that you become properly acquainted with their quirks.

In recent weeks, thousands of women have flooded a viral Reddit thread with the things they didn’t know about men until they started a relationship with one.

After all, women typically approach communication, affection and organisation differently, if the clichés are to be believed.

Here’s some of the discoveries female explorers made a little later in life…

The penis

Penises, honestly… they’re pretty fascinating — especially since they can have a mind of their own.

For @kpie007, ‘morning wood’ – a slang term that involves waking up with an erection – came as a surprise. ‘I had absolutely no idea that s**t just pops up every night till I started dating my first boyfriend,’ she wrote.

Some were surprised that men’s penises changed so much in size when hot and cold (Picture: Getty Images)

She wasn’t alone in her shock. ‘NRB’s (no reason boners). Like, it just happens? For no reason?? Wild,’ said @Ocelotkitty.

But unexpected erections weren’t the only thing that left some a bit baffled. Men’s testes were another hot topic.

‘The ball sack physically moves around and you can see when it gets looser or tightens. It’s super fascinating to look at, you can also feel it. And the man can’t control it,’ wrote @Viking_gurrrrl.

‘How often they need to readjust their balls,’ added @username00990.

The ability of the penis to drastically change in size was another discovery.

Redditor @jessicaeatseggs wrote: ‘How different a penis can look soft vs erect. And how much it can shrink in the cold.’

Communication

With basic anatomy out of the way, some women also revealed how shocked they were at the level of communication men have — largely with each other.

This goes for all men including father figures, rather than just guys in relationships.

‘My mum rings to arrange a time to talk properly: 10 minutes,’ wrote @Deanomatronix. ‘My Dad rings for an update on my career/health/relationship: 53 seconds.’

Some women feel men’s communication styles are a lot more to the point and more abrupt (Picture: Getty Images)

Some guys even chimed in to share how confused the women in their lives had been at their communication styles.

‘My ex-wife was shocked at how short a phone conversation can be for dudes. My best friend called me once, this man literally flew across the country once to be at our wedding, called me because he was bringing me to work the next day,’ said @Tommyboy3111.

‘”Still need a ride?”, “Yep”, “Ok I’ll be there at 5:30”, “Sounds good”.’ he explained.

‘And that was it. She sat there astonished and was asking why didn’t we want to talk to each other? I really had no good answers either, it’s just the way she goes I guess.’

Another brilliant example of this was mentioned by @Britta_is_in_this. They wrote: ‘My favorite cousin texted me:

‘”We got engaged, best man?”

‘”Yep!”

‘”Cool.” His wife is still baffled by it.’

When it came to communicating in a romantic relationship dynamic, another woman shared a more serious discovery she’d made.

‘When they ask you to leave them alone, they absolutely mean it,’ she said.

Affection

As women grow up, it can be easy to buy into the societal stereotype that men are stoic and don’t need much affection.

Some women feel men don’t get nearly enough compliments and couldn’t believe how much one meant to them (Picture: Getty Images)

But, if you’ve dated a guy, you’ll know that this really isn’t the case.

‘Most of them are way into cuddling and having their heads rubbed,’ said @LilStabbyboo.

Another @abbeyfinch6 revealed: ‘A lot of them literally go months or years without any meaningful physical contact.

‘It’s kinda sad but on the other hand you feel great being the one person in the world making them happy.’

Compliments are another form of affection and it seems a lot of women were surprised at just how far a simple compliment could go with their men.

‘I told my guy that I loved his shirt and he didn’t even know what to say. He told me he couldn’t remember the last time someone complimented him so I’ve started looking for little, random things to compliment him on,’ wrote @classy_rachael.

‘I noticed this with my husband a while back. Whenever I tell him that something he wears makes him look nice, he’ll wear it as often as possible. If he tries something on while shopping that I think looks good on him, he’ll buy it and put it on as soon as we get home. I love that guy,’ shared @Moxymoron221.

‘They LOVE compliments and will hold onto them for years,’ added another.

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