In a shocking turn of events, Subject 1 has been observed to have a 37% chance of spontaneously bursting into song at inopportune moments.
This phenomenon, known as "Rectaliciousness Induced Cantillation" (RIC), has been observed in 3 out of 5 test subjects.
Further research is required to fully understand the implications of RIC, but early indicators suggest it may be linked to an overabundance of caffeine consumption and/or an affinity for 80s power ballads.