Last Christmas, I gave you my heart, but the very next day you gave it away. This year, to save me from tears, I'll give it to someone special... And so on, and so on. I'm sure, you do know the lyrics. Almost everyone do. One of the main reasons, why do we know Christmas songs so well, is that every year they repeat so many times that you unconsciously learn both, the melody and the lyrics. Even if you don't like all those super happy Christmas songs when you first heard it, it's more than probable that after a few years you will start first humming it, then singing it and finally loving it. It's because of the so called 'exposure effect'. The scientists claim that the more often we hear a particular song, the more we like it. So if you still don't like Christmas music, just keep listening to it!

Let's say it clear, there are two main reasons why do we yawn: we usually yawn when we are bored or when we are tired. When you have to read another essay that makes you almost fall asleep, but you force yourself to finish it so you keep reading, and reading... I'm sure that at some point you start yawning. Or after a long day at work, when you have no more energy to call a pizza delivery place so you just sit on a couch doing nothing... You yawn a few times or more. But when we see someone yawning, we yawn too. Actually, sometimes thinking about it, forces us to do it, even if we are not neither bored nor tired. So why do we yawn then? And, is yawning contagious? Well, it definitely is and I'm sure you already know about it. But do you know why? It's a one of the common forms of echophenomena which is an automatic imitation of somebody's actions.  So, are you already yawning?

  You're preparing a family dinner: no meat and no onion for mum, but a lot of meat and a lot of onions for dad instead. Your brother is a seafood lover while your fianc é won't take a bite of anything that lives in the sea. Too complicated? Try to remember who likes olives, blue cheese, mushrooms and brussels sprout and who hates it, only to get to know that it's completely not true, because in the last few weeks everything has changed. Why do we like foods that we used to hate before? The main reason is, our taste buds regenerate. The scientists claim, it happens every two or three weeks until we celebrate our 40th birthday. Then the whole process slow down, and we don't notice the changes anymore.

The answer seems to be obvious: as dogs bark, birds chirp, cows moo and some other animals squeak, oink or quack, cats meow - it is their way to communicate. But is it true? Well, yes and no... In the last few weeks, I was asked to take care of three cats. What I found out, is that they meowed only when they wanted to communicate with me. When they were playing of fighting with each other, they either hissed or growled At some point, I asked myself: why do they actually meow? I googled it and it turned out that cats meow only at humans! And the sound of each meow depends on what cats want to tell us: it is different when they want food, it is different when they are annoyed and they want to grab the attention, and it is different when they are angry and they want us to leave them alone. Of course, they use other sounds to communicate with us too, but the fan fact to know is that they never meow at each other.

This morning, when I was preparing my breakfast, it happened again: my sandwich fell to the floor, buttered side down. Maybe it's just a coincidence, or I have a permanent bad luck, but it happens to me every single time when I accidentally drop my sandwich.  In fact, there is a scientific explanation, why does bread usually fall buttered side down. There's even a site on Wikipedia dedicated to Buttered toast phenomenon . Let's just say, without mentioning unnecessary law of physics, that when you hold a toast or when you put it on the kitchen table, it is at the perfect level to rotate and land the buttered side on the floor. If you want to avoid it, there are some rules you can follow. You can cut the bread into smaller slices, or you can try to elevate the surface that you are working on , which will probably change the number of rotations and hopefully make the bread land on the desirable side. The shape of the slice is also important- if you make it a

It's kind of weird, but it happens to almost everyone. We take a long, relaxing bath. After a couple of minutes our hands start to look different and we can notice some changes. First, some small wrinkles start to appear on our finger pads and later on you can tell that they are on the whole palm. It shouldn't be a surprise for anyone that they remain for some time, but there's no reason to be worried about it. But why does it happen? And what is more curious, is there any purpose of this change? Even if that's quite funny, and maybe for some of you a little bit disgusting, from the scientific point of view there may be a purpose of the wrinkles that we can see on our fingers. The biologists claimed that it could be one of the evolutionary traits that help us adapt to the wet conditions. Just think about trying to grab a shampoo with wet hands while having a bath. Much easier if you have those wrinkles, don't you think?

Now, when Christmas is over and we start preparing ourselves for the New Year's Eve, we also start thinking about the promises for the New Year. The most common one regards changing a bad habit, like quitting smoking, starting a diet or more generally introducing a healthy lifestyle. But on the other hand, it may be also an excuse to start learning a new language or travel to a place when we have never been before. We may promise to spend more time with the family or dedicate our free time to a voluntary organization. But where did this tradition of New Year's resolutions come from?  From what I've known, it is due to the Romans and their mythical god named Janus. He has two faces: one looking forward and one looking backward, what symbolically means that he can see the past and the future at the same time, that he is looking backward into the past year and forward into the new year and that is why Romans start reflecting about their resolutions. And th