the late Catacomb period with a surrounding ditch has been found. Ceramics Catacomb ceramics are more elaborate than those of the Yamnaya culture. Low footed vessels that have been discovered in female burials are believed to have been used in rituals that included the use of narcotic substances such as hemp. Catacomb ceramics appears to have influenced the ceramics of the Abashevo culture and the Sintashta culture. Weapons Evidence of early composite bows have been yielded from the Catacomb culture. Quivers with space for ten to twenty arrows have also been found. Its arrowheads may have influenced those of the Sintashta culture. Its hollow-based flint arrowheads are similar to those of the Middle Dnieper culture. Stone battle-axes of the Catacomb culture are similar to those of the Fatyanovo–Balanovo culture. A knife from ca. 2500 BC ascribed to the Catacomb culture in the Donets had a handle of arsenical bronze and a blade made of iron. Other characteristics Wheeled vehicles have been found in Catacomb burials. Bronze warty beads of the Catacomb culture are similar to those of the Sintashta culture. Certain variants of the Catacomb culture, particularly those centered at the Donets, appear to have practiced cranial deformation. This may have been an aesthetic device or an ethnic marker. Around 9% of Catacomb skulls had holes drilled into them. This appears to have been associated with a ritual or medical practice. Remains of bears have been found at Catacomb sites. Demographics The Catacomb culture is estimated to have included some 50,000-60,000 individuals. Physical type The Catacomb people were massively built Caucasoids/Europoids. Their skulls are similar to those of the Potapovka culture. Potapovka skulls are less dolichocephalic than those of the Fatyanovo–Balanovo culture, Abashevo culture, Sintashta culture, Srubnaya culture and Andronovo culture. The physical type of the Potapovka appears to have emerged through a mixture between the strongly dolichocephalic type of the Sintashta, and the less dolichocephalic type of the Yamnaya culture and Poltavka culture. The people of the Catacomb culture have been described as "stockier and had more brachycephalic crania" than individuals belonging to the Yamnaya culture. According to two craniological studies, "the Catacomb culture skulls supposedly showed Mediterranean features, indicating their possible migration into the region from the Armenian Highland and the Caucasus." Genetics Pashnik et al. (2014) analyzed the DNA of the remains of 28 Catacomb individuals. Their maternal haplogroups U5 and U4 appeared in higher frequencies than