DOI: 10.5061/dryad.dncjsxm8q
title: Hidden causes of variation in offspring reproductive value: negative effects of maternal breeding age on offspring telomere length persist undiminished across multiple generations

description: Offspring of older breeders frequently show reduced longevity, which has
 been linked to shorter offspring telomere length. It is currently unknown
 whether such telomere reduction persists beyond a single generation, as
 would be the case if germline transmission is involved. In a
 within-grandmother, multi-generational study using zebra finches, we show
 that the shorter telomeres observed in F1 offspring of older mothers is
 still present in the F2 generation even when the breeding age of their F1
 mothers is young. The effect was substantial - 43% shorter telomeres in
 grandoffspring from the ‘grandmother old at breeding’ line compared with
 those from the ‘grandmother young at breeding’ line. Shorter telomeres at
 fledging in this species are associated with a reduction in lifespan. Our
 data demonstrate the need to look beyond a single generation to explain
 inter-individual variation in ageing rates, and thereby variation in
 optimal allocation of age-specific reproductive effort.
description: # Hidden causes of variation in offspring reproductive value: negative
 effects of maternal breeding age on offspring telomere length persist
 undiminished across multiple generations by Valeria Marasco, Winnie Boner,
 Kate Griffits, Shirley Raveh, & Pat Monaghan ## Data Description
 Telomere length: T/S ratio (Telomere repeat copy number / GAPDH) Body
 mass: grams ### Data1_ELE-00395-2024.csv dataset to analyse effect of
 grandmother (F0) age at breeding on grandoffspring (F2) body mass and
 telomere length at 30 days of age. Description of variables (from left to
 right): * F2 Ring: id F2 bird * Gen: Generation of birds (i.e., F2, F2.2)
 * TEL: Telomere length at 30-day sampling * D30_Mass: Body mass at 30-day
 sampling * Sex: sex of F2 bird * Hatch_Nest: nest id of F2 bird *
 Chick_Num: hatching order of F2 bird * Cluth_site: size of the clutch from
 which F2 bird originates * ID_mother_of_F2: mother id of F2 bird -
 TEL_Mother_of_F2: telomere length at 30-day sampling of the mother of F2
 bird (i.e., F1 female) - ID_Father_of_F2: Father id of F2 bird - ID_F0: id
 of F0 female ### Data2_ELE-00395-2024.csv dataset to analyse changes in
 30-day telomere length of females across the three generations (F0, F1,
 and F2), separately by grandmother breeding event. Description of
 variables (from left to right): * Gen: Generation of birds (i.e., F0, F1,
 F2, F1.2, F2.2) * F0_Breeding: indicates age at breeding of F0 female
 (i.e., young adulthood, or old adulthood) * ID: Telomere length at 30-day
 sampling * ID_F0: id of F0 female ### Data3_ELE-00395-2024.csv dataset to
 analyse differences in breeding performance of F1 daughters used to
 generate the F2 birds. Description of variables (from left to right): *
 ID_mother_of_F2: mother id of F2 bird (i.e., F1 female) * Gen: Generation
 of birds (i.e., F2, F2.2) * Clutch_size_F2: size of the clutch produced by
 F1 mother * N_F2_reared: number of reared F2 birds by F1 mother * ID_F0:
 id of F0 female * Mass_mother_breeding: Body mass at breeding of F1 female