The mountain pygmy possum (Burramys parvus) population at Mount Buller was small and inbred. In September 2011 six males from Mount Higginbotham, in the central part of the range (isolated from Mount Buller for at least 20,000 years), were released there, and four of them sired young that season. More males, from Timms Spur, were released in September 2014. Possums were trapped every spring and genotyped at 24 microsatellites.
Format
A list with:
- alleles
Integer matrix, 536 rows x 48 columns: allele sizes at 24 microsatellites, two columns per locus (
locus.a1,locus.a2;NAmissing), as used bymicrosat_markers().- groups
"ref1"(Mount Buller 2010, before the rescue, 29),"ref2"(Mount Higginbotham 2012, the source population, 104),"Buller2011"to"Buller2015"(Mount Buller by year; 40, 43, 67, 103 and 138),"Higginbotham_males_2011"(the six males released in 2011) and"TimmsSpur_males_2014"(the six released in 2014).- truth
Data frame, one row per group:
group,n,year,years_since_rescue,hybrid_age(expected mean hybrid age of the hybrids, where known),max_hybrid_age(upper bound) andnote.- animals
Data frame, one row per row of
alleles:id,tag,group,yearandnew_this_year(first year the tag was caught at Mount Buller).- description
A short description.
Source
Data package of Weeks et al. (2017) on Dryad,
doi:10.5061/dryad.7g988
(file
Burramys_parvus_genotypic_data_Mt_Buller.xlsx). CC0 1.0.
Truth
Possums breed as one-year-olds, so the oldest possible hybrid generation equals the number of years since the 2011 breeding season. Buller 2011 was trapped as the first males were released and is pure. In 2012 every hybrid is an F1 (hybrid age 1; the authors found 13). In 2013 the new adults were F2s and backcrosses with no new F1s (6 F2 and 23 backcrosses), and surviving F1s returned, so the hybrids average about 1.5 generations. In 2014 hybrids are at most 3 generations old, but new F1s also appeared (one 2011 male first bred in 2013, and captive-bred animals with some Higginbotham ancestry were released after the 2013 trapping); in 2015 they are at most 4 generations old, with new F1s from the Timms Spur males. The mean generation time is 1.54 years. Animals caught in several years appear once per year, so year groups overlap. Alleles from Timms Spur that Mount Higginbotham lacks appear in the 2015 sample.
Licence
The genotypes are from Dryad and were released under CC0 1.0 (public domain dedication). Rows were reordered and labelled; allele sizes are unchanged. No locality data are included.
References
Weeks AR, Heinze D, Perrin L, Stoklosa J, Hoffmann AA, van Rooyen A, Kelly T, Mansergh I (2017) Genetic rescue increases fitness and aids rapid recovery of an endangered marsupial population. Nature Communications 8:1071. doi:10.1038/s41467-017-01182-3
Examples
ms <- microsat_markers(possums$alleles, possums$groups, "ref1", "ref2")
y12 <- possums$groups == "Buller2012"
table(classify_hybrids_microsat(possums$alleles[y12, ], ms)$class)
#>
#> F1 pure1
#> 13 30
sc <- hybrid_scores_microsat(possums$alleles, ms)
aggregate(cbind(S, H) ~ group, data.frame(sc, group = possums$groups), mean)
#> group S H
#> 1 Buller2011 0.0005000 0.001000000
#> 2 Buller2012 0.1451163 0.284651163
#> 3 Buller2013 0.1692537 0.300000000
#> 4 Buller2014 0.1951456 0.322330097
#> 5 Buller2015 0.2617391 0.347246377
#> 6 Higginbotham_males_2011 0.9766667 0.020000000
#> 7 TimmsSpur_males_2014 0.9233333 0.063333333
#> 8 ref1 0.0000000 0.000000000
#> 9 ref2 0.9909615 0.009423077