Homo neanderthalensis, also known as Neanderthals, were a species of ancient humans that lived in Europe and parts of Asia about 400,000 to 40,000 years ago. They are the closest extinct human relative, sharing a common ancestor with modern humans.
Neanderthals had a stocky build, with a robust and muscular body adapted for cold climates. They had a larger brain size than modern humans, with a prominent brow ridge and distinct facial features.
Neanderthals were skilled hunters and used tools such as spears and stone tools for hunting and butchering animals. They also had symbolic behavior, as evidenced by the use of pigments and the burial of their dead.
The reasons for the extinction of Neanderthals are still debated, but factors such as climate change, competition with modern humans, and interbreeding with modern humans are considered to have played a role in their disappearance.