Three-quarters of the earth is covered in water, which is pretty remarkable when you consider seven billion humans live on our planet.
In addition to all of the humans, there are also around seven million species of land animals which means the world is full of living, breathing organisms on just 25-percent of it.
What about the other 75-percent?
Scientists believe there are around 2.2 million species of creatures living in the earth’s waters.
Out of these two-plus million species, there are some really, really strange ones.
Scientists discovered a prehistoric shark that they have determined has existed for 80 million years.