Catalogue of Life

The Catalog of life was created by Light as a list of all organic matter. It is the work of centuries. When Light went to sleep life started to evolve. Light was angered because now the catalog was invalid and contained no knowledge of many secies that now dominated the earth incuding humans. Light was shown by The Doctor that life would always evolve so life gave up on the catalog and dispersed.

It is proven that the catalog contained information on Neanderthals as Light had taken the specimen known as Nimrod. It is also probable that it contained information on reptiles and insects as there where Husks of these in the lower observatory of Gabriel Chase, the house at which Light's ship is situated. (DW: Ghost Light)

What sort of object this is is not made clear whether it was a books, hologram or some other device.