A closer look at invasiveness and relatedness: life histories, temperature, and establishment success of four congeners (original) (raw)
Related papers
2015
This thesis aims to contribute to the understanding of the invasive success of two invasive fishes (Gambusia affinis and G. holbrooki). We reviewed four Internet databases and the literature to clarify their introduction history and geographical distribution, establish their introduction routes, and analyse predictors of their invasive success. A meta-analysis of the ecological impacts of mosquitofishes shows that the overall impact is: i) similar for the two species; ii) clear and strong for fish, macroinvertebrates, amphibians, and some zooplanktonic groups and more variable for taxa at lower trophic levels and for ecosystem features; iii) general for the number of aggressive acts received and decreases in density and biomass but more variable for other response variables; and iv) highly heterogeneous and context-dependent on a number of features. We estimated the mean critical swimming speed (Ucrit) of G. holbrooki as 14.11 cm s-1, which is lower than for many other fish of simil...
Invasiveness of an introduced species: the role of hybridization and ecological constraints
Biological …, 2011
Introduced species are confronted with new environments to which they need to adapt. However, the ecological success of an introduced species is generally difficult to predict, especially when hybridizations may be involved in the invasion success. In western Europe, the lake frog Pelophylax ridibundus appears to be particularly successful. A reason for this species' success might be the presence of the invader's genetic material prior to the introduction in the form of a hybrid between P. ridibundus and a second indigenous water frog species. These hybrids reproduce by hybridogenesis, only transmitting the ridibundus genome to gametes and backcrossing with the indigenous species (i.e. P. lessonae). This reproductive system allows the hybrid to be independent from P. ridibundus, and allows the ridibundus genome to be more widely spread than the species itself. Matings among hybrids produce newly formed P. ridibundus offspring (N), if the genomes are compatible. Therefore, we hypothesize that hybridogenesis increases the invasiveness of P. ridibundus (1) by enhancing propagule pressure through N individuals, and/or (2) by increasing adaptation of invaders to the native water frogs' habitat through hybrid-derived ridibundus genomes that are locally adapted. We find support for the first hypothesis because a notable fraction of N tadpoles is viable. However, in our seminatural experiments they did not outperform ridibundus tadpoles in the native water frogs' habitat, nor did they differ physiologically. This does not support the second hypothesis and highlights ecological constraints on the invasion. However, we cannot rule out that these constraints may fall with ongoing selection, making a replacement of indigenous species highly probable in the future.
The elephant in the room: the role of failed invasions in understanding invasion biology
Oikos, 2013
Most species introductions are not expected to result in invasion, and species that are invasive in one area are frequently not invasive in others. However, cases of introduced organisms that failed to invade are reported in many instances as anecdotes or are simply ignored. In this analysis, we aimed to find common characteristics between non-invasive populations of known invasive species and evaluated how the study of failed invasions can contribute to research on biological invasions. We found intraspecific variation in invasion success and several recurring explanations for why non-native species fail to invade; these included low propagule pressure, abiotic resistance, biotic resistance, genetic constraints and mutualist release. Furthermore, we identified key research topics where ignoring failed invasions could produce misleading results; these include studies on historical factors associated with invasions, distribution models of invasive species, the effect of species traits on invasiveness, genetic effects, biotic resistance and habitat invasibility. In conclusion, we found failed invasions can provide fundamental information on the relative importance of factors determining invasions and might be a key component of several research topics. Therefore, our analysis suggests that more specific and detailed studies on invasion failures are necessary.
Resolving the genetic basis of invasiveness and predicting invasions
Genetica, 2007
Considerable effort has been invested in determining traits underlying invasiveness. Yet, identifying a set of traits that commonly confers invasiveness in a range of species has proven elusive, and almost nothing is known about genetic loci affecting invasive success. Incorporating genetic model organisms into ecologically relevant studies is one promising avenue to begin dissecting the genetic underpinnings of invasiveness. Molecular biologists are rapidly characterizing genes mediating developmental responses to diverse environmental cues, i.e., genes for plasticity, as well as to environmental factors likely to impose strong selection on invading species, e.g., resistance to herbivores and competitors, coordination of life-history events with seasonal changes, and physiological tolerance of heat, drought, or cold. Here, we give an overview of molecular genetic tools increasingly used to characterize the genetic basis of adaptation and that may be used to begin identifying genetic mechanisms of invasiveness. Given the divergent traits that affect invasiveness, ''invasiveness genes'' common to many clades are unlikely, but the combination of developmental genetic advances with further evolutionary studies and modeling may provide a framework for identifying genes that account for invasiveness in related species.
Aquatic Sciences, 2022
Understanding the invasion success of alien species includes developing knowledge on how the biological traits of their populations respond to spatial differences in environmental conditions. For invasive fishes, while the influence of latitudinal and climatic gradients on their biological traits over large spatial scales are well established, there is less certainty in how these vary over smaller scales. Here, we tested the influence of a climatic and geographic gradient on the reproductive traits and body sizes of the invasive mosquito fish Gambusia holbrooki across five climatic regions in Turkey. The results revealed that the environmental conditions across eight sites provided two gradients: a latitudinal gradient (where northern sites were cooler with less rainfall) and a coastal-inland gradient (where changes were apparent from coastal areas and into inland areas). These gradients had marked effects on the traits of both sexes, in sites in coastal and southern areas, male had significantly larger gonopodia and females had higher egg numbers than in inland and warmer areas, and with both sexes having body sizes that were smaller. The spatial differences in the male traits were suggested as being driven by differences in selection pressures at the sites that related to differences in their population abundances. The results revealed that environmental conditions across a relatively small spatial scale had some strong influences on the expression of specific biological traits of these mosquito fish populations, but with further work needed to test how these influences affect their invasion success.
Journal of Biogeography, 2021
AimHumans influence species distributions by modifying the environment and by dispersing species beyond their natural ranges. Populations of species that have established in disjunct regions of the world may exhibit trait differentiation from native populations due to founder effects and adaptations to selection pressures in each distributional region. We compared multiple native, expansive and introduced populations of a single species across the world, considering the influence of environmental stressors and transgenerational effects.LocationUnited States Gulf and Atlantic coasts, United States interior, European Atlantic and Mediterranean coasts, east coast of Australia.TaxonBaccharis halimifolia L. (eastern baccharis).MethodsWe monitored seed germination, seedling emergence, survival and early growth in a common garden experiment, conducted with over 18,200 seeds from 80 populations. We also evaluated the influence of environmental stress and maternal traits on progeny performan...