http://www.youtube.com/watch?v=oPm1whfqtH4
In Digimon Data Squad a human partner evokes a D.N.A. (Digimon Natural Ability, originally "Digisoul") within themselves. A D.N.A. is a manifestation of a human partner's emotions that they can send to their Digimon to prompt evolution. Some non-partnered Digimon feed off the negative thoughts of people to evolve in this series. The call is "D.N.A., Charge!".
If that doesn't explain enough then google it.