  It is shown that LHC data can allow one to decode the mechanism by which dark
matter is generated in the early universe in supersymmetric theories. We focus
on two of the major mechanisms for such generation of dark matter which are
known to be the Stau Coannihilation (Stau-Co) where the neutralino is typically
Bino like and annihilation on the Hyperbolic Branch (HB) where the neutralino
has a significant Higgsino component. An investigation of how one may
discriminate between the Stau-Co region and the HB region using LHC data is
given for the mSUGRA model. The analysis utilizes several signatures including
multi leptons, hadronic jets, b-tagging, and missing transverse momentum. A
study of the SUSY signatures reveals several correlated smoking gun signals
allowing a clear discrimination between the Stau-Co and the HB regions where
dark matter in the early universe can originate.
