Résumé
Rapid adaptation to global change can counter vulnerability of species to
population declines and extinction. Theoretically, under such
circumstances both genetic variation and phenotypic plasticity can
maintain population fitness, but empirical support for this is currently
limited. Here, we aim to characterise the role of environmental and
genetic diversity, and their prior evolutionary history (via haplogroup
profiles) in shaping patterns of life history traits during biological
invasion. Data were derived from both genetic and life history traits
including a morphological analysis of 29 native and invasive populations
of topmouth gudgeon Pseudorasbora parva coupled with climatic variables
from each location. General additive models were constructed to explain
distribution of somatic growth rate (SGR) data across native and invasive
ranges, with model selection performed using Akaike’s Information
Criteria. Genetic and environmental drivers that structured the life
history of populations in their native range were less influential in
their invasive populations. For some vertebrates at least, fitness related
trait shifts does not seems to be dependent on the level of genetic
diversity or haplogroup make-up of the initial introduced propagule, nor
of the availability of local environmental conditions being similar to
those experienced in their native range. As long as local conditions are
not beyond the species physiological threshold, its local establishment
and invasive potential are likely to be determined by local drivers, such
as density dependent effects linked to resource availability or to local
biotic resistance.