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Full-Text Articles in Life Sciences
Sex Chromosome Turnover In Bent-Toed Geckos (Cyrtodactylus), Shannon E. Keating, Madison Blumer, L. Lee Grismer, Aung Lin, Stuart V. Nielsen, Myint Kyaw Thura, Perry L. Wood Jr., Evan S.H. Quah, Tony Gamble
Sex Chromosome Turnover In Bent-Toed Geckos (Cyrtodactylus), Shannon E. Keating, Madison Blumer, L. Lee Grismer, Aung Lin, Stuart V. Nielsen, Myint Kyaw Thura, Perry L. Wood Jr., Evan S.H. Quah, Tony Gamble
Biological Sciences Faculty Research and Publications
Lizards and snakes (squamates) are known for their varied sex determining systems, and gecko lizards are especially diverse, having evolved sex chromosomes independently multiple times. While sex chromosomes frequently turnover among gecko genera, intrageneric turnovers are known only from Gekko and Hemidactylus. Here, we used RADseq to identify sex-specific markers in two species of Burmese bent-toed geckos. We uncovered XX/XY sex chromosomes in Cyrtodactylus chaunghanakwaensis and ZZ/ZW sex chromosomes in Cyrtodactylus pharbaungensis. This is the third instance of intrageneric turnover of sex chromosomes in geckos. Additionally, Cyrtodactylus are closely related to another genus with intrageneric turnover, Hemidactylus. …
Xx/Xy Sex Chromosomes In The South American Dwarf Gecko (Gonatodes Humeralis), Tony Gamble, Erin Mckenna, Wyatt Meyer, Stuart V. Nielsen, Brendan J. Pinto, Daniel P. Scantlebury, Timothy E. Higham
Xx/Xy Sex Chromosomes In The South American Dwarf Gecko (Gonatodes Humeralis), Tony Gamble, Erin Mckenna, Wyatt Meyer, Stuart V. Nielsen, Brendan J. Pinto, Daniel P. Scantlebury, Timothy E. Higham
Biological Sciences Faculty Research and Publications
Sex-specific genetic markers identified using restriction site-associated DNA sequencing, or RADseq, permits the recognition of a species’ sex chromosome system in cases where standard cytogenetic methods fail. Thus, species with male-specific RAD markers have an XX/XY sex chromosome system (male heterogamety) while species with female-specific RAD markers have a ZZ/ZW sex chromosome (female heterogamety). Here, we use RADseq data from 5 male and 5 female South American dwarf geckos (Gonatodes humeralis) to identify an XX/XY sex chromosome system. This is the first confidently known sex chromosome system in a Gonatodes species. We used a low-coverage de novo G. …
Into The Light: Diurnality Has Evolved Multiple Times In Geckos, Tony Gamble, E. Greenbaum, Todd R. Jackman, Aaron M. Bauer
Into The Light: Diurnality Has Evolved Multiple Times In Geckos, Tony Gamble, E. Greenbaum, Todd R. Jackman, Aaron M. Bauer
Biological Sciences Faculty Research and Publications
Geckos are the only major lizard group consisting mostly of nocturnal species. Nocturnality is presumed to have evolved early in gecko evolution and geckos possess numerous adaptations to functioning in low light and at low temperatures. However, not all gecko species are nocturnal and most diurnal geckos have their own distinct adaptations to living in warmer, sunlit environments. We reconstructed the evolution of gecko activity patterns using a newly generated time-calibrated phylogeny. Our results provide the first phylogenetic analysis of temporal activity patterns in geckos and confirm an ancient origin of nocturnality at the root of the gecko tree. We …
Restriction Site-Associated Dna Sequencing (Rad-Seq) Reveals An Extraordinary Number Of Transitions Among Gecko Sex-Determining Systems, Tony Gamble, Jessi Coryell, Tariq Ezaz, Joshua Lynch
Restriction Site-Associated Dna Sequencing (Rad-Seq) Reveals An Extraordinary Number Of Transitions Among Gecko Sex-Determining Systems, Tony Gamble, Jessi Coryell, Tariq Ezaz, Joshua Lynch
Biological Sciences Faculty Research and Publications
Sex chromosomes have evolved many times in animals and studying these replicate evolutionary “experiments” can help broaden our understanding of the general forces driving the origin and evolution of sex chromosomes. However this plan of study has been hindered by the inability to identify the sex chromosome systems in the large number of species with cryptic, homomorphic sex chromosomes. Restriction site-associated DNA sequencing (RAD-seq) is a critical enabling technology that can identify the sex chromosome systems in many species where traditional cytogenetic methods have failed. Using newly generated RAD-seq data from 12 gecko species, along with data from the literature, …
A New Genus Of Miniaturized And Pug-Nosed Gecko From South America (Sphaerodactylidae: Gekkota), Tony Gamble, Juan D. Daza, Guarino R. Colli, Laurie J. Vitt, Aaron M. Bauer
A New Genus Of Miniaturized And Pug-Nosed Gecko From South America (Sphaerodactylidae: Gekkota), Tony Gamble, Juan D. Daza, Guarino R. Colli, Laurie J. Vitt, Aaron M. Bauer
Biological Sciences Faculty Research and Publications
Sphaerodactyl geckos comprise five genera distributed across Central and South America and the Caribbean. We estimated phylogenetic relationships among sphaerodactyl genera using both separate and combined analyses of seven nuclear genes. Relationships among genera were incongruent at different loci and phylogenies were characterized by short, in some cases zero-length, internal branches and poor phylogenetic support at most nodes. We recovered a polyphyletic Coleodactylus, with Coleodactylus amazonicus being deeply divergent from the remaining Coleodactylus species sampled. The C. amazonicus lineage possessed unique codon deletions in the genes PTPN12 and RBMX while the remaining Coleodactylus species had unique codon …
A Review Of Sex Determining Mechanisms In Geckos (Gekkota: Squamata), Tony Gamble
A Review Of Sex Determining Mechanisms In Geckos (Gekkota: Squamata), Tony Gamble
Biological Sciences Faculty Research and Publications
Geckos are a species-rich clade of reptiles possessing diverse sex determining mechanisms. Some species possess genetic sex determination, with both male and female heterogamety, while other species have temperature-dependent sex determination. I compiled information from the literature on the taxonomic distribution of these sex determining mechanisms in geckos. Using phylogenetic data from the literature, I reconstructed the minimum number of transitions among these sex determining mechanisms with parsimony-based ancestral state reconstruction. While only a small number of gecko species have been characterized, numerous changes among sex determining mechanisms were inferred. This diversity, coupled with the high frequency of transitions, makes …