AGH wrote the paper, contributed to conception and design of the study, sampled fish, generated adaptive trait and genetic data, and carried out most of the subsequent analyses.
These phenotypic changes have a genetic basis but are partly due to a direct response to chemical cues from fish via adaptive phenotypic plasticity.
On the one hand, in the ancestor of jawless fish, an adaptive immune system arose that was based on variable lymphocyte receptors generated by somatic recombination of modules coding for leucine rich repeats [ 15].
Our results suggest that immediately following the introduction of fish predators, adaptive plasticity may reduce the impact of selection through "Baldwin/Bogert effects" by facilitating the movement of populations toward new fitness optima.
In fish, multiple adaptive mechanisms can mediate survival at low temperatures, such as the synthesis of antifreeze proteins in Antarctic fish, endothermy in salmon sharks, the presence of a heater organ in swordfish and the enhancement of oxidative capacity in the striped bass and crucian carp (for a review, see Hochachka and Somero, 2002).
This is good news for the fisheries manager and is in agreement with other research on fishing-induced evolution pointing to the possibility of counteracting fishing-induced adaptive changes through appropriate harvest regulations (Conover and Munch 2002; Ernande et al. 2004; Baskett et al. 2005) or gear choices (Jørgensen et al. 2009).
Our results show that reductions in egg number and body size of D. melanica genotypes from the Sierra Nevada, in response to introduced fish, are largely adaptive evolutionary responses and not due entirely to adaptive phenotypic plasticity.
Many experimental approaches were tried with the aim of converting fish keratocyte's adaptive random migration into ECM path-guided movement.
Furthermore, agnathan fish possess an adaptive immune system based entirely on clonal rearrangement of LRRs rather than immunoglobulins and the resulting LRR domains demonstrate specificity for individual strains of bacteria [33] [36].
Although an adaptive fish keratocyte showing active calcium oscillations could still traverse the FBN path (Fig. 4A), the movement of crossing was slow and the cell appeared to be "dragged" along the way by the substrate, as compared to the fast crossing motion exerted by the adaptive cell showing no calcium transient (Fig. 4B).
