DOI: 10.5061/dryad.0rxwdbs5m
title: Data from: the role of male quality in sequential mate choice: pregnancy replacement in small mammals?

description: Females mainly increase their reproductive success by improving the
 quality of their mates and need to be discriminative in their mate
 choices. Here we investigate whether female mammals can trade up sire
 quality in sequential mate choice during already progressed pregnancies. A
 male-induced pregnancy termination (functional ‘Bruce effect’) could thus
 have an adaptive function in mate choice as a functional part of a
 pregnancy replacement. We used bank voles (Myodes glareolus) as a model
 system and exchanged the breeding male in the early second trimester of a
 potential pregnancy. Male quality was determined using urine marking
 values (UMV).  Females were offered a sequence of either high
 then low-quality male (HL), or a low then high-quality male (LH). The
 majority of females bred with the high-quality male independent of their
 position in the sequence, which may indicate a pregnancy replacement in LH
 but not in HL. The body size of the second male, which could have been
 related to the coercion of females by males into re-mating, did not
 explain late pregnancies. Thus, pregnancy replacement, often discussed as
 a counterstrategy to infanticide, may constitute adaptive mate choice in
 female mammals.
description: Each female was paired with male 1 for a duration of 7 days (5-8
 days in dataset 2), after which the male was removed and replaced with the
 second male (M2), which stayed with the female for another 7 days. For the
 experiment males were placed into females' cages to mimic the natural
 situation where males would enter females' territory. On an
 experimental day 14, pairs were separated and all animals were transferred
 back into their single-home cages. Due to the bank vole pregnancy lasting
 20 ± 2 days (mean ± SD, we expected litters born on experimental days 18
 to 32. Cages were controlled daily for births. We
 challenged our paternity assignment for the litters born in the second
 peak (days 25 – 29) in dataset 1, using genetic paternity analyses. We
 assigned paternity to 10 out of 11 families using genetic parentage
 analyses and confirmed 9 out of 10 of our assignments (90%), and one
 litter had a change in the assignment. Multiple males sired none of the
 litters. One family did not have any of the males confirmed as fathers,
 due to missing genetic samples.
description: # Data from: the role of male quality in sequential mate choice: pregnancy
 replacement in small mammals? --- To choose an attractive male can be
 beneficial for female’s fitness, considering that the genes that male
 possesses could increase offspring viability and/or mating success.We use
 bank voles (*Myodes glareolus*) as study system, since it has been showed
 that 50% of females exhibit turnover of pregnancies after male turnover in
 the field and lab. For this experiment we chose males of different
 qualities perceivable to human observers, i.e., experimental dominant
 males (or high quality, “HQ”) will have a higher UMV, will be larger, and
 bolder than experimental subordinate males (low quality, “LQ”). The second
 male will be offered one week after the first one, and females can only
 achieve a trade-up of sire quality by terminating the first pregnancy. Our
 results suggest that, as predicted, the pregnancy turnover rate was higher
 when the second male was high quality. ## Description of the data and file
 structure In this dataset you can find individual information (ID, weight,
 sex,date of giving birth etc.). For more detailed explanation please read
 the paper. All weight mesurments are presented in grams (g). Description
 of the variables:     1. date M1/M2 in - the date when a certain male was
 paired with a female     2. rank M1/M2 - male quality category that each
 male was given after 3 tests     3. Treatment - a male quality sequence
 that was presented to the female     4. nr_sq_M1/M2 - number of squares
 covered with urine in the dominance test (max. 35)     5. abs_UMV -
 proportion of squares covered by urine after 3 tests     6. inf_M1/M2 -
 infanticidal category for each male (0 = non-infanticidal, 1 =
 infanticidal)     7. BDAY1/2 - how many days have passed from pairing with
 the first male and with the second male to the birth of the litter; to
 determine the sire of the litter     8. rep.to.first/second.male - did the
 female reproduce with the first or second male (0 = no, 1 = yes) In the
 genetic analyses table all the unites here presented are number of
 nucleotides per microsatellite. Missing data code: NA