Hybridization between subterranean tuco-tucos (Rodentia, Ctenomyidae) with contrasting phylogenetic positions

Abstract

Jorge c. pereira 5 , edivaldo Herculano corrêa de oliveira 6,7 , Malcolm A. ferguson-Smith 5 & thales Renato ochotorena de freitas 1,2,3 Reproductive compatibility usually decreases according to increasing genetic difference and the time of divergence between species. However, the amount of modification required to influence hybridization may vary in different species. Thus, it is extremely important to conduct studies that seek to understand what and how variables influence the reproductive isolation of species. We have explored a system involving two species of subterranean rodents that present morphological, karyotypic, and evolutionary history differences and are capable of generating hybrids. To gain insight into the karyotype organization of genus Ctenomys, we examined the chromosome evolution by classical and molecular cytogenetics of both parental species and hybrids. Furthermore, we have used different approaches to analyze the differences between the parental species and the hybrids, and determined the origin of the hybrids. The results of our work demonstrate unequivocally that some species that present extensive differences in chromosome organization, phenotype, evolutionary history, sperm morphology and genetic, which are usually associated with reproductive isolation, can generate natural hybrids. the results also demonstrate that females of both species are able to generate hybrids with males of the other species. In addition, the chromosome-specific probes prepared from Ctenomys flamarioni provide an invaluable tool for comparative cytogenetics in closely related species.

Using Telomeric Length Measurements and Methylation to Understand The Karyotype Diversification of Ctenomys Minutus (A Small Fossorial Mammals)

“…2g). This ITS region may indicate a fusion between chromosomes 7 and 5 of C. amarioni, found recently in the cytotype 2n= 46a of C. minutus by Kubiak et al 42 . De Freitas 43 comparing the karyotypes of C. lami 2n=54 and 2n=46a of C. minutus found the fusion of chromosomes 13 and 23 of C. lami to form pair 1 of C. minutus.…”

Penile shape discriminates two cryptic species of Akodon Meyen, 1833 (Mammalia, Rodentia, Cricetidae) from eastern Brazil

“…For the quantitative characters, the glans of the hybrid subgroup morphologies was not clearly associated with one of the parental species and the hybrids seem to have a distinct identity from their parental species, probably due to the combination of the expression of these characters independently. This pattern is observed in characters of the skull of subterranean tuco-tucos, whose combination of parental features generates a distinct configuration ( Kubiak et al 2020 ). Characters that display intermediate metrics compared to parentals seem to follow a complex multigenic determinism due to additive genetic variation in hybrids ( Renaud et al 2012 ).…”

Genetic footprints of Quaternary climatic fluctuations on the endangered Tuco-tuco-das-dunas (Ctenomys flamarioni)

“…Information provided herein is important to conservation management since C. flamarioni is an endangered species endemic to the coastal dunes of Rio Grande do Sul, as cited on the IUCN red list (Freitas et al 2019). Its narrow range of distribution, changes in the habitat quality due to human use (mainly in the north of its distribution) associated the population bottlenecks and effects of inbreeding (Fernández-Stolz et al 2007), as well as competition and hybridization events with C. minutus in areas of sympatry (Kubiak et al 2017, 2020) place C. flamarioni at significant threat of genetic erosion, highlighting the need for urgent conservation measures.…”

“…Ctenomys flamarioni has been widely studied regarding its cytogenetics (Freitas 1994; Massarini and Freitas 2005; Kubiak et al 2020), population ecology (Fernández-Stolz et al 2007; Garcias et al 2018), morphology (Fornel et al 2018), distributional range (Freitas 1995; Kubiak et al 2015, 2017), and population genetics (Fernández-Stolz et al 2007). However, this is the first study to evaluate the phylogeography of C. flamarioni over its entire distributional range.…”