Mind the lag: understanding genetic extinction debt for conservation.

The delay between disturbance events and genetic responses within populations is a common but surprisingly overlooked phenomenon in ecology and evolutionary and conservation genetics. If not accounted for when interpreting genetic data, this time lag problem can lead to erroneous conservation assessments. We (i) identify life-history traits related to longevity and reproductive strategies as the main determinants of time lags, (ii) evaluate potential confounding factors affecting genetic parameters during time lags, and (iii) propose approaches that allow controlling for time lags. Considering the current unprecedented rate of loss of genetic diversity and adaptive potential, we expect our novel interpretive and methodological framework for time lags to stimulate further research and discussion on the most appropriate approaches to analyse genetic diversity for conservation.