18 lens regrowths in 16 years
Eguchi and colleagues removed the lens 18 times from the same newts over 16 years; even in animals 30 years old, the regrown lenses matched normal ones.
As reported in: Eguchi, Eguchi, Nakamura et al. (2011). Regenerative capacity in newts is not altered by repeated regeneration and ageing. Nature Communications. doi:10.1038/ncomms1389