Accession Number : ADA292863

Title :   Corpus Callosum Size in Deiphinid Cetaceans.

Descriptive Note : Professional paper,

Corporate Author : NAVAL COMMAND CONTROL AND OCEAN SURVEILLANCE CENTER RDT AND E DIV SAN DIEGO CA

Personal Author(s) : Tarpley, R. J. ; Ridgway, S. H.

PDF Url : ADA292863

Report Date : DEC 1994

Pagination or Media Count : 12

Abstract : The midsagittal surface area of the corpus callosum was determined by computer-assisted morphometry in juvenile and adult members of 13 species of the cetacean family Delphinidae. In 57 brains, absolute callosal areas ranged from 104 to 829 mm2. When compared to other mammal groups possessing a corpus callosum, callosal area in dolphins was smaller in relation to brain mass with a ratio range (mm2/g)) of 0.08-0.31. The corpus callosum was decreased relative to brain mass in the larger-brained odontocetes, suggesting that increases in brain size were not necessarily allied with needs for equivalent increases in callosal linkage. One delphinid species, Tursiops truncatus, for which the largest single- species sample was available, was examined for sex differences in callosal size relative to brain mass. Among 10 males and 5 females the averaged ratio was not distinguishable between sexes.

Descriptors :   *SIZES(DIMENSIONS), *BRAIN, *DOLPHINS(MAMMALS), RATIOS, MAMMALS, MASS, MORPHOLOGY, SURFACES, COMPUTER APPLICATIONS, SEX.

Subject Categories : Biology
      Anatomy and Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE