1. In Australia, birds of prey deliberately start forest fires - wielding flaming sticks to do so. Indigenous people have known of these 'firehawk raptors' for quite some time, but now we also have scientific research describing this stunning phenomenon.
2. Here's an update on what you learned in high school biology - this year we discovered mitochondrial DNA can actually be passed down by males.
3. Scientists have figured out an incredible method for making it rain in the Sahara Desert, and if we went ahead with something so grand, it could produce all the power the world currently uses more than four times over.
4. Viruses are literally raining on us from the sky all the time. In fact, hundreds of millions of viruses per day are deposited above the lowest layer of the atmosphere - much more than anyone suspected.
5. There are ancient messages hidden in the world around us. While Europe was wilting in a surprising heatwave this summer, a drying river in Czechia revealed a dire warning from 1616 carved into sinister 'hunger stones'.
6. It's possible to build a device that generates particles with what appears to be 'negative mass'. These bizarre particles are called polaritons, and they're half-light, half-matter. Cooooool.
7. There's a micro-organ in the human immune system we previously didn't know about. Layered on top of lymph nodes, the thin, flat structures appear to work like biological headquarters for planning a counter-attack to infection.
8. The answer really is 42! More specifically, when scientists counted all the protein molecules in a yeast cell, they were surprised (and we presume delighted) to discover the answer was 42 million.
9. Speaking of cells – for the first time, researchers captured insane footage of a bacterium using its appendages to fish for little bits of DNA from its dead friends. It's just as incredible as it sounds.
11. There are fish out there that basically have switchblades under their eyes. They're pretty freaky.
12. Neuroscientists can now connect the brains of three people, enabling them to share thoughts. This wild, pioneering experiment was a proof of concept, and the volunteers played a Tetris-style game together. The end goal? Whole networks of people, all linked together with their minds. Let that sink in.
13. Birds can see magnetic fields - how else would they be able to migrate across our planet as extensively as they do? Now we know that the reason they can achieve this impressive feat is thanks to a special protein in their… eyes.
14. One of the most common antidepressants might actually be breeding antibiotic resistance.
15. You can sail almost 20,000 miles (32,186 km) in an uninterrupted straight line - from Pakistan to the Kamchatka Peninsula, Russia.
16. Tiny marine 'insects' can generate surprisingly huge, intense ocean currents, researchers found - an idea that's been "almost heretical" in oceanography.
17. The world's largest underwater cave is officially located in Mexico, and it spans a staggering 347 kilometres (216 miles). Not only is this branching labyrinth a spectacle to behold, it is also full of Maya secrets and treasures. Bonus fact: This year, scientists also found a gigantic unexplored cave in Canada that may have never been seen with human eyes.
18. Up to 90,000 Americans think their bodies are infested by insects. Really.
19. There's more to human DNA than the double helix. Earlier this year, scientists identified a DNA structure never before seen in living cells. They described it as a 'twisted knot', a shape previously only seen in the lab.
20. There's a massive biosphere of life hidden under Earth's surface - and the scale of this 'dark biosphere' is so much larger than previously imagined.
21. Scientists identified a common driving force behind all humanity's darkest impulses. Meet 'D', the 'dark factor of personality'.
22. On a related note, Washington DC is the psychopath capital of the US, according to this study... and we're not entirely surprised.
23. An invisible boundary that has helped divide the US for centuries is now shifting, thanks to climate change. It's called the 100th meridian west and it roughly bisects the continental US in half.
24. It's totally possible to make a sheep-human hybrid. These chimeras, resulting from human stem cells introduced into sheep embryos, could one day represent the future of organ donation.
25. Lightning inside 2015's record-breaking Hurricane Patricia was so intense, it blasted a beam of antimatter at Earth.
26. It takes more than just an X and Y chromosome to determine a baby's sex. Scientists discovered a new genetic regulator that plays a big role in determining whether a baby is born male or female.
27. Sloths have a metabolism so weird, scientists have never seen anything like it in the animal kingdom before. ¯\_(ツ)_/¯
28. And finally, we also now know the worst year in human history to be alive. Not only was it decidedly not 2018, it's a year you likely haven't even heard of: 536 CE.