Human disturbance as a possible cause of genetic introgression from exotic into native Mauremys turtles

Abstract

The Kinmen Islands on the coastline of China represent a recent case of the protection of endangered wildlife in a demilitarized zone. These islands represent the last remaining habitat in southeastern China that supports a healthy natural population of Reeves’ turtle Mauremys reevesii. However, human‐mediated dispersal appears to have aided the establishment of an introduced population of the Chinese stripe‐necked turtle M. sinensis since the late 1990s, resulting in population mixture of the two congeners. To evaluate the potential impacts of hybridization, we evaluated the magnitude of genetic introgression in ponds on Kinmen using mitochondrial cytochrome b sequences and 13 microsatellite loci. We further used eight environmental and biological factors of the ponds to conduct general linear regression model analysis between environmental factors and the magnitude of genetic introgression. Among the 41 sampled ponds, M. reevesii was recorded in 21, of which 12 ponds (57.1%) contained genetic hybrids or backcrosses, corresponding to 11.3–12.7% of the total individuals on the islands. The magnitude of genetic introgression was positively correlated with the amount of introduced M. sinensis occurring in a pond, and marginally negatively associated with the shortest distance from the pond to secondary roads. We conclude that this considerable genetic introgression is attributable to human‐mediated dispersal of M. sinensis; roads and habitat modification may increase the likelihood of unexpected encounters between these two congeners.

Development of novel high-resolution melting markers for the assessment of hybridization betweenMauremys sinensisandMauremys reevesiiin South Korea

“…Ueno et al [41] revealed a cross-back hybrid between M. japonica and M. reevesii and reported that the fertility and hatchability of F1s of M. japonica and M. reevesii were not significantly different from those of the parental species, posing a potential threat to the conservation status of M. japonica , which is endemic to mainland Japan. In addition, Lee et al [9] reported that imported M. sinensis caused genetic introgression in native M. reevesii populations in the protected area, raising a critical risk to their conservation.…”

“…In addition, Lee et al [9] reported that imported M. sinensis caused genetic introgression in native M. reevesii populations in the protected area, raising a critical risk to their conservation.…”

Interstitial Telomeric Repeats Are Rare in Turtles

“…As these inversions are important for the evolution of postzygotic reproductive isolation mechanisms, and thus speciation [ 120 , 121 , 122 , 123 , 124 ], this feature may contribute to the generally low species diversity in turtles [ 70 ] and their slow molecular evolution [ 125 , 126 , 127 ]. The low rate of inversions in the karyotype evolution of turtles could explain why they exhibit a high incidence of genomic introgression and why they extensively hybridize (and are often able to produce fertile offspring), even after many million years of divergence, as documented in chelid, cheloniid and geoemydid turtles [ 81 , 91 , 128 , 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 ].…”

Insight into the Genetic Population Structure of Wild Red Foxes in Poland Reveals Low Risk of Genetic Introgression from Escaped Farm Red Foxes

“…As a result of the human-mediated movement of animals, it is becoming increasingly important to understand and manage genetic introgression and its effects [ 13 ]. Accidentally or intentionally introduced wild or domestic species can interbreed with their domesticated counterparts [ 3 , 14 , 15 , 16 ]. Gene flow from domesticated animals may carry alleles that may increase the fitness of the wild animals, so natural selection will drive introgression [ 3 ].…”