One hundred million years ago, Antarctica was covered in thick forests, inhabited by dinosaurs. It was a time of warmth, when the polar ice-caps had practically melted. Robert Scott in 1912, was the first to notice fossilised plants. Later Jane Francis of the University of Leeds, as well as others, discovered more. Francis found stunted beech bushes, which were only 3 to 5 million years ago. These plants and trees survived despite unusual polar conditions of night or darkness throughout the winter, and sun and light throughout the summer.
Polar dinosaurs may have lived there throughout the year. A complete dinosaur skeleton was found of Leaellynasura, which looked somewhat like a small kangaroo, lived on plants, and had enlarged optic lobes, indicating it could see in the dark.
Another dinosaur known from its fossils was a meat-eating creature, more than 2 metres tall, living in the James Ross region of Antarctica. It was probably a Titanosaur.
There is also evidence of tetrapods living in Antarctica 245 million years ago.
A meteorite from Mars is believed to have fossilised microbial life.
Recently, there are claims of tiny humanoid fossils being found, which existed 600 million years ago!
Given what we know about human evolution, this is a near impossibility, and I am yet to see something about this in a scientific journal.
But obviously, Antarctica has many mysteries that are still to be discovered.