- Data Deficient
- deciduous
- Demersal
- dental formula
- dentary bone
- denticle
- denticulate
- Derived
- dermal
- dermatoglyphic
- dermis
- desert
- desmosomes
- diarrhea
- diastema
- dichotomous
- dichotomy
- Dideriaecea
- diffuse
- diffusion
- digastric muscle
- dilated
- dimorphic
- diploid
- Discriminant analysis
- Discrimination
- disjunct
- dispersal
- Dispersal biogeography
- dissected
- dissection
- distad
- distal
- Distance
- Distance matrix
- Distance variables
- distributed
- diurnal
- divergence
- DNA
- Dollo characters
- domestic
- dorsal
- dorsum
- drongo
- dry season
- duk-duk
- dune