| boundary zone between northern and southern pig-tailed macaques and their morphological differences. | based on previous conflicting reports that the two forms of pig-tailed macaque (northern and southern) exist as separate species, subspecies, or forms, and that their boundary zone lies in thailand, a survey of the distribution range and morphology of pig-tailed macaques in thailand was conducted during 2003-2010. we first conducted a questionnaire survey. questionnaires were sent to 7,410 subdistricts throughout thailand. we then traveled to 72 of the 123 subdistricts reporting the presence of ... | 2012 | 22820844 |