From the new parasite that ate the shark brains to stray dogs turning blue, 2017 fathered some freaky mysteries. Despite science being able to find an explanation for just about everything, some happenings remain unexplained.

From February to August, masses of San Francisco sharks, rays, and fish inexplicably died. After a bit of testing, the cause of death was determined to be Miamiensis Avidus, a parasite that was eating away at the brains of the creatures. The parasite entered through the gills of the animals and traveled to their brains, but it is unclear how so many parasites were able to affect such a population, given that it was the first time wild sharks had fallen victim to it. Theories include rain levels and a larger shark population, but the deaths remain perplexing.

In Egypt, the Great Pyramid of Giza was found to have a mysterious cavity above the entrance to the tomb of the pharaoh Khufu. The area was found through subatomic particle scanning and remains unexplored by archaeologists. Whether or not the space is a room or multiple rooms cannot be certain, and whatever is contained within it remains a mystery as well.

After over a dozen radio bursts were heard from space in September, a galaxy lying three billion light years away was determined to be the source. There have been over 20 similar incidents reported since they were first detected 11 years ago, but the reason for receiving these blasts from different galaxies is unknown. Although some of the galaxies were discovered to have a strong magnetic field, this factor hasn’t been linked to causing the signals.

In October, over 20 dead octopuses washed up on the shores of Wales for an unknown reason. Many people speculated that the recent hurricane had caused it, but others turned to more biological theories. Scientists proposed that the octopuses could have turned senile and had simply died in the same area or were driven to the shore in further search of food because of the flourishing population. Whether or not it is a combination of some of these theories or something entirely different, the reason behind the wash-up remains unsolved.

If these mysteries weren’t enough, dozens of stray blue dogs were spotted around India. The one things the dog had in common was their act of wading and swimming in wastewater, and when washed, the blue color was found to be a dye. Fortunately, the dye was confirmed as non-toxic by National Geographic, but the chemical and factory causing the dye pollution of the water have either not been identified or released by the authorities.

These puzzling 2017 events still haven’t been explained and might forever remain that way. What mysteries does 2018 have in store? Only time will tell.