DOI: 10.5061/dryad.h70rxwdsj
title: The effects of costly telomere maintenance on lifespan-reproductive tradeoffs in sand lizards

description: Telomeres are DNA-protein structures that primarily protect chromosomes
 and serve multiple functions of gene regulation. When cells divide,
 telomeres shorten and their main repair system in ectotherms - telomerase
 – replaces lost nucleotide complexes ((T2AG3)n in vertebrates). It remains
 a challenge to experimentally investigate resource requirements for
 telomere maintenance and its effects on lifespan-reproductive tradeoffs in
 the wild. In sand lizards (Lacerta agilis), we show that higher female
 investments into reproduction result in corresponding shortening of
 telomeres and that males have less frequent and less profound telomere
 shortening than females; a contributing factor to this may be males’
 higher telomerase levels. To manipulate resource access for telomere
 maintenance, we exploit a pseudo-experimental opportunity to analyze
 ‘onboard’ resources long-term using lizards that drop their tails with fat
 and nutrient deposits when attacked by predators. Females with fewer
 resources regrow tails less often and less profoundly elongate telomeres.
 Adult lizards with the most TL elongation live the longest, females with
 the highest lifetime reproductive success shorten telomeres the most,
 whereas males with the most telomere elongation have the highest lifetime
 reproductive success. This suggests ongoing evolution of
 resource-constrained telomere maintenance.
description: Long-term field work on sand lizards followed by molecular
 analyses
description: # Terminal decisions: lifespan-reproductive effort balance set by telomere
 maintenance in an ectotherm Dryad DOI:
 [https://doi.org/10.5061/dryad.h70rxwdsj](https://doi.org/10.5061/dryad.h70rxwdsj) Data description for ‘The effects of costly telomere maintenance on lifespan - reproductive tradeoffs in sand lizards’ Note: Empty boxes in Excel always denote missing values – a result of incomplete sampling of lizards in the wild throughout the decade-long sampling period (you can think of catchability through lizard life as a ‘sliding window’ with only some lizards being followed completely from birth to death. #### File: FeCostOfReproRev  Variables: Adult number ('adno') = is the sequential identification number of each adult lizard DNAquality (A260/280) ('aDNAqual') = is the ratio of absorbance at 260 and 280 nm is **used to assess DNA purity**. Regenerated tail (mm) ('reg') = our lizards drop their tail when attacked by a predator, whereafter the tail regrows, and we measure the regrown part in mm Body mass ('mass')= the lizard is weighed in (g) Clutch mass ('cmass') = is the weight in (g) of a female's total egg clutch weighed after it's laid log(TSRatio as adult) ('tTSAd') = is the log-transformed factual telomere length estimate using qPCR (i.e., the telomere-single copy gene ratio - here we used GAPDH as a single copy gene) #### File: Telomerasedata Variables: date ('date') = observation data when the data was collected sex ('sex') = the lizards sex, M = male, F = females RNAconcentration ('RNAconc') = RNA concentration in the blood scored in (ng/µl) TERTexpression(Cq) ('tTERTCqIPCgDNACorr') = gene expression of the TERT gene that produces telomerase and adds base pairs to the telomere at the end of the chromosome regenerated tail in mm ('reg') #### File: TeloTerminalRev Variables: adult number ('adno') = an adult lizard's identification number sex ('sex') = a lizard's sex, M = male, F = female year of measurement ('myear') = the year an observation was made DNAquality (A260/280) ('aDNAqual') = is the ratio of absorbance at 260 and 280 nm is **used to assess DNA purity** Regenerated tail in mm ('reg') = the regrown part of the tail subsequent to tail dropping after a predator attack Mort ('mort') = classification variable that defines whether a lizard died (dead) or lived on (alive) til the next year Lifetime reproductive success (counts) ('lrs') = the number of offspring produced during an individual lizard's lifespan. The number is acquired by assigning maternity and paternity of offspring using 21 microsatellites (molecular markers) Lifespan ('mlspan') = a lizard's lifespan in years TSRatio ('tTSAge') = the telomere length estimated using T/S ratio (i.e., telomere length divided by the single copy gene GAPDH) Change in TS ratio controlling from hatchling to adult (i.e., telomere length at hatching minus the telomere length as adult) ('DRegToMeanCorr') Classification of regenerated vs. intact tail (''reg1') Further explanations to the above file: intact vs. regenerated tail is a classification variable used to contrast lizards that have lost their tail from predator attacks and are currently regrowing a tail, versus those that have never lost their tail due to predation. Lifetime reproductive success is the cumulated number of offspring molecularly assigned using 21 microsatellites.