Requirement
1. Four terms, and what makes a mammal a mammal
Required
Animal, invertebrate, vertebrate and mammal explained, then three characteristics that distinguish mammals from every other animal. The three characteristics are the part with a number attached to it.
Notes and warnings
Note. The 2025 requirements book's version of this badge stops at requirement 5. Requirement 6, on Leave No Trace and the Outdoor Code, and requirement 7, the careers and hobby choice, are on the current page only, so a printed book is not a complete second source for this badge.
Where this step comes from
- Mammal Study Merit Badge Requirements (Merit Badge Hub, last modified 2025-12-31), Requirement 1