The spinal cord is the most phylogenetically ancient part of the central nervous system. The more rapid growth of the spine in relation to the spinal cord in ontogenesis leads to the fact that in adult mammals some segments of the spinal cord are shifted ro strally in relation to the eponymous vertebrae, which is called ascension of the spinal cord. Based on literature data, we compared the skeletotopy of the lumbar spinal cord of 17 species of mammals. In 4 species, we also compared the skeletotopy of newborn and adult animals. The ratio of the length of the L2 segment to the length of the VL2 vertebra and the number of the vertebra in which the 29th segment of the spinal cord is located, characterizing the degree of ascension, were determined. Based on literature data, we determined characteristics frequently used in comparative studies: finger dexterity and encephalization coefficient. It has been shown that different species differ to a greater extent in the relative length of the rostral lumbar segments, and within the same species, newborns differ from adults in the relative length of the caudal lumbar segments. For most species, the degree of spinal cord ascension significantly positively correlates with finger dexterity and the encephalization coefficient. The considered macroanatomical characteristics of the spinal cord may be used to analyze the relationships between adaptive mechanisms in various mammalian species.
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