Boekind

Boekind was a species from the Silver Devastation.

Biology
Boekind were large, humanoid heads with numerous tendrils which terminated in round pod-like structures in place of hair. (TV: The End of the World)

Boekind can communicate telepathically and are able to speak, though they often preferred telepathy. (TV: The End of the World, New Earth, Gridlock)

It is possible that immortals of other races may become Boekind after an extremely long life. This is not proven, and the only evidence to it is that Captain Jack Harkness, an immortal human said that people used to call him the Face of Boe, which is the name of a Boekind that the Doctor met in the future.(TV: "Utopia")

Life cycle
Little is known about Boekind reproduction, but based on a newscast by BadWolfTV, it is possible that they could become pregnant. (TV: The Long Game)

Technology
The only technology known to be used by Boekind was a life support tank with added teleport in which the Face of Boe lived permanently. However, even this may have not been created by Boekind, and may have been a creation of another race. (TV: The End of the World, New Earth, Gridlock)

History
In the year 200,000, the Face gave birth to the Boemina, (TV: The Long Game) although by the time of his hospitalisation and near-death in 5,000,000,023 they were deceased. The Face managed to survive, (TV: New Earth) but later sacrificed himself to save the inhabitants of New New York in the year 5,000,000,053. (TV: Gridlock)