1) Male seahorses are the ones who give birth to their offspring.

2) The world's largest volcano, Mauna Loa in Hawaii, is also one of the most active.

3) The oldest known musical instrument is a flute made from a bird bone, estimated to be around 43,000 years old.

4) Democracy is a system of government in which power is vested in the people, who exercise it through elected representatives. It allows for political participation, freedom of speech, and protection of individual rights and liberties.