title: Lineage identification and genealogical relationships among captive Galápagos tortoises.
abstract: Genetic tools have become a critical complement to traditional approaches for meeting short- and long-term goals of ex situ conservation programs. The San Diego Zoo (SDZ) harbors a collection of wild-born and captive-born Galápagos giant tortoises (n = 22) of uncertain species designation and unknown genealogical relationships. Here, we used mitochondrial DNA haplotypic data and nuclear microsatellite genotypic data to identify the evolutionary lineage of wild-born and captive-born tortoises of unknown ancestry, to infer levels of relatedness among founders and captive-born tortoises, and assess putative pedigree relationships assigned by the SDZ studbook. Assignment tests revealed that 12 wild-born and five captive-born tortoises represent five different species from Isabela Island and one species from Santa Cruz Island, only five of which were consistent with current studbook designations. Three wild-born and one captive-born tortoise were of mixed ancestry. In addition, kinship analyses revealed two significant first-order relationship pairs between wild-born and captive-born tortoises, four second-order relationships (half-sibling) between wild-born and captive tortoises (full-sibs or parent-offspring), and one second-order relationship between two captive-born tortoises. Of particular note, we also reconstructed a first-order relationship between two wild-born individuals, violating the founder assumption. Overall, our results contribute to a worldwide effort in identifying genetically important Galápagos tortoises currently in captivity while revealing closely related founders, reconstructing genealogical relationships, and providing detailed management recommendations for the SDZ tortoises.
authors.affiliation: Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA. edgar.benavides@yale.edu
authors.forename: Edgar
authors.initials: E
authors.lastname: Benavides
authors.forename: Michael
authors.initials: M
authors.lastname: Russello
authors.forename: Donal
authors.initials: D
authors.lastname: Boyer
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Wiese
authors.forename: Brittney
authors.initials: B
authors.lastname: Kajdacsi
authors.forename: Lady
authors.initials: L
authors.lastname: Marquez
authors.forename: Ryan
authors.initials: R
authors.lastname: Garrick
authors.forename: Adalgisa
authors.initials: A
authors.lastname: Caccone
mesh_terms: D000818:Animals; D000835:Animals, Wild; D000836:Animals, Zoo / Q000235:genetics*; D005819:Genetic Markers; D023281:Genomics; D006239:Haplotypes / Q000235:genetics*; D018895:Microsatellite Repeats / Q000235:genetics*; D014426:Turtles / Q000235:genetics*
chemical_list: D005819:Genetic Markers