Baby slings provided an external womb - in which immature infants could continue their development in reasonable safety and security. The innovation broadly resembles a marsupial's pouch.
Sling manufacturing techniques are culturally-transmitted today - and probably this was always the case.
Baby slings are ancient - the date of their arrival has been traced via the study of lineages of associated lice.
Baby slings probably reduced infant mortality, providing a strong survival advantage to newborns of mothers with the relevant memes. The relaxed selection pressure on cranial size turned out to be a highly significant phenomenon for all memes. Larger brains meant more space for the memes. By providing the technology to facilitate the growth of the human brain, the memes had come across a way of dramatically expanding their own living quarters.
- Tyler, Tim (2011) Big brains as meme nests
- Tyler, Tim (2011) The big brain as a meme nest
- Tyler, Tim (2012) The external womb
- Caldwel, Duncan (2008) The Baby-Sling Hypothesis for Human Evolution
- Taylor, Timothy (2010) The Artificial Ape: How Technology Changed the Course of Human Evolution
- Taylor, Timothy (2010) Slings & arrows