Data from: No evidence that life history strategies shape within-body mosaics of ageing

Tissues across the body may age at different rates, which creates
within-body mosaic ageing. Life history strategies shape ageing patterns
at the inter- and intra-specific level, but the impact of life history
strategies on mosaic ageing patterns within individuals remains unknown.
Reproductive tissues in individuals selected to prioritise reproduction
may age faster than somatic tissues because of increased ‘wear and tear’.
Alternatively, individuals that prioritise reproduction may specially
protect reproductive tissues at the expense of somatic tissues to allow
for increased reproductive function. Here, we used Japanese quail
(Coturnix japonica) artificially selected for increased vs. reduced
reproductive investment (egg size) to test how reproductive strategies
modulate within-body variation in ageing patterns, by measuring telomere
length as an ageing biomarker in blood, spleen and reproductive tissue
(oviduct and testis). We did not find evidence that reproductive strategy
shaped within-body mosaics of ageing: patterns of telomere length in
somatic and reproductive tissues were similar in individuals selected for
high and low reproductive investment, respectively, and strong positive
correlations in telomere length across tissues were observed. Our results
suggest that life history strategy does not affect tissue-specific ageing
rate. Alternately, ‘wear and tear’ and ‘special protection’ mechanisms
might act simultaneously and cancel each other out, resulting in similar
telomere lengths across tissues.