In general, experiments flown on the Bion missions encompass a broad range of important investigations that expand our understanding of a variety of fundamental and applied life sciences questions. During Bion 11, scientists from the United States, France and Russia studied physiological responses of two male rhesus monkeys to the microgravity environment experienced in earth orbit. Fields of investigation included the effects of weightlessness on bone, muscle and neuromuscular structure and function, sensorimotor function, behavior, circadian rhythms, fluid and electrolyte balance and immunology. The scientists also studied the readaptation to normal gravity following landing.
Other experiments performed during the Bion 11 mission included the study of physiological responses to microgravity by Dileptus anfer (a protist), Pottia and Caretodou mosses on agar, Lepidium savita L. seedlings on a solid substrate, fruit flies, black body beetles, Spanish newts, and a radiation experiments on dry seeds, nucleotides and bacterial spores.
Bion 11 was successfully completed when the spacecraft landed in Kazakhstan on January 7, 1997. Tragically, Multik died the day after the capsule was recovered during his post-landing medical operation and checkup. The Bion 11 and 12 investigations were to be a two-mission scenario with major objectives aimed at understanding the source of muscle and bone weakening in space. Multik's death raised questions regarding the ethics of using animals for research. Therefore, NASA has dropped participation in the Bion 12 mission, which was scheduled for launch in July, 1998.