Why are nonhuman primates used only when necessary?

• A. When another animal cannot be used; moral & ethical implications
• B. They are the most expensive option
• C. They are easier to handle
• D. They require special housing

Answer: (A)

The key idea is that nonhuman primates are reserved for uses that truly require them because of ethical and regulatory concerns about their high cognitive abilities and capacity to suffer. Researchers must first show that no other species can achieve the scientific goals, and that the potential benefits justify the ethical costs. This aligns with the 3 Rs approach—replace if possible, reduce numbers, refine procedures to minimize suffering—and with stricter oversight for primates. So the reason they’re used only when necessary is precisely to address moral and ethical implications and to ensure alternatives have been considered. Costs, ease of handling, or housing needs aren’t the primary justification for this restriction.