- diakinesis
- diapause
- Dicotyledoneae
- differential gene activity
- differential reproduction
- differentiation
- digestion
- dignity of animals
- dinophany
- dinosaur
- dioecia
- diplobiontic
- diploid
- diplont
- diplophase
- diplotene
- direct/indirect fitness
- directional selection
- discontinuous variation
- disease
- disjunct species