Abstract
BackgroundIn contrast to the explosive increase of a population following biological invasion, natural dispersal, i.e., when a population disperses from its original range into a new range, is a passive process that is affected by resources, the environment, and other factors. Natural dispersal is also negatively impacted by genetic drift and the founder effect. Although the fates of naturally dispersed populations are unknown, they can adapt evolutionarily over time to the new environment. Can naturally dispersed populations evolve beneficial adaptive strategies to offset these negative effects to maintain their population in a stable state?ResultsThe current study addressed this question by focusing on the toad Bombina orientalis, the population of which underwent natural dispersal following the Last Glacial Maximum in Northeast Asia. Population genetic approaches were used to determine the genetic structure, dispersal pattern, and mating system of the population of B. orientalis in northeast China (Northern population). The results showed that this northern population of B. orientalis is a typical naturally dispersed population, in which the stable genetic structure and high level of genetic diversity of the population have been maintained through the long-distance biased dispersal behavior of males and the pattern of promiscuity within the population.ConclusionsOur findings suggest that naturally dispersed populations can evolve effective adaptive strategies to maintain a stable population. Different species may have different strategies. The relevance of these maintenance mechanisms for naturally dispersed populations provide a new perspective for further understanding the processes of speciation and evolution.
Highlights
In contrast to the explosive increase of a population following biological invasion, natural dispersal, i.e., when a population disperses from its original range into a new range, is a passive process that is affected by resources, the environment, and other factors
258 concatenated mtDNA Mitochondrial cytochrome c oxidase subunit I gene (COI) (903 bp) and Mitochondrial cytochrome b gene (Cytb) (885 bp) samples were used for genetic diversity analysis
Fong et al focusing on the genetic structure of B. orientalis populations, reported that this is a representative species of amphibians in Northeast Asia, and that its northern population originated from the peninsula population [10]
Summary
In contrast to the explosive increase of a population following biological invasion, natural dispersal, i.e., when a population disperses from its original range into a new range, is a passive process that is affected by resources, the environment, and other factors. The natural dispersal of a population is a complex process, which is affected by resource competition and environmental change, and the time between the occurrence of dispersal behavior to the formation of a new species distribution pattern is significant [6]. Such dispersal provides a prerequisite for the evolution of adaptive traits (e.g. behavioral phenotypes). Different from the rapid expansion of population after the biological invasion, if the naturally dispersed population need to form a stable geographical pattern, it will inevitably experience genetic drift, the founder effect, inbreeding depression and many other evolutionary processes that may lead to population decline [7, 8]. Can the naturally dispersed population evolve adaptive strategies that offset these negative effects to maintain a stable or even differentiated population?
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
