Question: How do primates compare with non-primate mammals in terms of gestation length? Need Assignment Help? Select the best answer from those provided. Primates tend to have gestation periods that are greater in length compared with most other mammals. Primates tend to have gestation periods that are shorter in length compared with most other mammals. Primates tend to have gestation periods that are about the same length as most other mammals. Primates are highly variable in their gestation period, with some groups having longer gestation than most other mammals and some groups having shorter gestation than most other mammals.