 Many of the skeletal features that distinguish the dodo and the Rodrigues solitaire , its closest relative , from pigeons have been attributed to their flightlessness . The pelvic elements were thicker than those of flighted pigeons to support the higher weight , and the pectoral region and the small wings were paedomorphic , meaning that they were underdeveloped and retained juvenile features . The skull , trunk and pelvic limbs were peramorphic , meaning that they changed considerably with age . The dodo shared several other traits with the Rodrigues solitaire , such as features of the skull , pelvis , and sternum , as well as their large size . It differed in other aspects , such as being more robust and shorter than the solitaire , having a larger skull and beak , a rounded skull roof , and smaller orbits . The dodo 's neck and legs were proportionally shorter , and it did not possess an equivalent to the knob present on the solitaire 's wrists . 
