Department of Archaeology, University of Oulu
April 16, 2020 , Platinum Ballroom
Compared to other primates human females possess considerably large amount of fat tissue around their mammary gland throughout adulthood. In this study we wanted to test a potential hypothesis that suggests that externally ample female breasts developed to support the neonatal body's thermal balance through increased skin contact, thereby compensating for the loss of insulating fur and the relative developmental helplessness of the newborn. To conduct this study we wanted to determinate how female breast tissue itself reacts in varied temperatures. Test was conducted in climatic chamber and was documented via thermal imaging.
Climatic chamber introduced three different temperatures (+32, +27, +18 degrees of Celsius) where volunteers (n=27) were tested in three 20 minute periods with 30 minutes intervals between, allowing the tissue enough time to adjust to the new temperature. The subjects' temperature was documented with a thermal imaging camera (FLIR SYSTEMS ThermaCAM PM695 PAL) and the data analyzed with the Thermacell researcher program. Our study revealed clear differences between our study groups; breastfeeding women had clear resilience to the decrease in temperature and maintained a higher and more even temperature under all temperature conditions compared to the breast tissue of the other two groups. Men's breast tissue temperature decreased the fastest and lowest among the groups. The pilot study indicates that in addition to a larger surface area, a woman's breast, especially breastfeeding, is also a more effective source of heat for neonate by itself.