You know that feeling you experience when you have a crush on someone? The nervousness, the excitement, the butterflies in your stomach - all of that combined is technically known as 'limerence', and scientists think it's caused by the release of adrenalin, which pulls blood away from areas of your body like your stomach, and towards the muscles where it could be better used (nudge, nudge, wink, wink).
But this lack of blood in the stomach could explain why when you're around someone you have a crush on, or you're sitting at home daydreaming about accidentally-on-purpose running into them at the cafe you both go to for your coffee, you can experience a lack of appetite when you feel 'love sick'.
But what happens when your crush decides to drop a bomb of disappointment on you while very awkwardly Friendzoning you? Biologically speaking, says Michael in the video above, the route towards the Friendzone might be explained by what's known as Bateman's Principle.
Named after English geneticist Angus Bateman, the principle states that whenever a species contains two different sexes, each with dissimilar sex cells - like sperm and eggs - it's inevitable that one sex is going to have to allocate more resources to the production of offspring than the other. This is particularly true in mammals, where females can only have a limited amount of offspring, but males can have as many as they please. Which means that one sex will end up being competitive with each other - in our case, the males - and the other to be choosey - so, the females.
So everyone's out there jostling and competing with each other, but not everyone who is rejected is an incredible jerk, as this episode of Vsauce points out. And what do you do to a really nice person you're not interested in sexually? You Friendzone them. Meanwhile, the person who has been Friendzoned has likely idealised their crush as a potential mate, but an unbiassed, neutral observer would probably tell you that you don't actually have that much in common. In other words, you and your crush are not as homogamous as you think you are.
So why then, do some incredible jerks seem to get all the mates? It could come down to what's known as the Scarcity Principle - we don't like our freedom to be limited in terms of what we can obtain, and that applies to our mate choice. It's a fascinating theory, and I'll let Michael explain in the video above how it could help you escape the Friendzone.
If you've been Friendzoned this Valentines Day, remember - no one can stop you from celebrating Anna Howard Shaw Day.