1) The blue whale is the largest animal to have ever existed, with an average length of about 82 feet (25 meters).

2) The world's most expensive car is the Bugatti La Voiture Noire, which sold for over $18 million.

3) In Norse mythology, the World Tree, known as Yggdrasil, is a massive ash tree that connects the nine realms of existence. It is considered the center of the cosmos and serves as a conduit between different realms, including Asgard (realm of the gods), Midgard (realm of humans), and Helheim (realm of the dead).

4) The world's oldest living plant is believed to be a clonal shrub called "Old Tjikko" in Sweden, estimated to be over 9,500 years old.