- macrochromosome
- Macroevolution
- macula
- Mahafely
- Mahalanobis distance
- Makoa
- malar foramen
- malaria
- male
- mamma
- mammal
- man-eating tree
- mandible
- mandibular angle
- mandibular corpus
- mandibular foramen
- mandibular incisura
- mandibular ramus
- Mangerivola
- mangrove
- Manhattan distance
- Maningozo
- Manombo
- Manongarivo
- MANOVA
- Mantady
- marbled
- marking
- Marojejy
- Marotandrano
- marsh
- Masikoro
- Masoala
- Mass extinction
- masseter
- mastoid
- mature
- maty
- maxilla
- Maximum likelihood
- meadow
- Mean
- meatus acusticus externus
- Mechanical isolation
- medial
- melanism
- membrane
- menalamba
- mend the mountains
- mental foramen
- Merina
- Meristic character
- Meristic variable
- merocrine
- mesad
- mesal
- mesial
- mesic
- mesoderm
- Mesopelagic
- Mesozoic
- metabolism
- metacentric
- metacone
- metaconid
- metamorphosis
- metazoa
- microchromosomes
- Microevolution
- micropaleontology
- mifindra
- mimicry
- Miocene
- mipetraka
- mitochodrion
- mitosis
- Modern synthesis
- molar
- molariform
- Molecular clock
- monocyte
- monogamy
- monophyletic
- Monophyletic group
- monotypic
- Montagne d'Ambre
- montane
- moorland
- morengi
- morpha
- morphology
- morphometric
- Morphometrics
- Morphospace
- mottled
- mpakafa
- mpisikidi
- mud
- mudflats
- multifurcate
- Multivariate normality
- MY
- myoepithelial cells