Adaptations for metabolic efficiency, extreme metabolic and physiological regulation, and extensive fluctuations in oxidative metabolism have made alethinophidian snakes an important model for physiological and metabolic research [10] [13], and the adaptation of COI seems certain to be related in some way to their unique metabolism and physiology.
The reasons for these extensive fluctuations are complex and reflect an intricate interplay of factors that control the natural cycle and transmission dynamics of TBE virus.
Woods suggests a reason for their extinction: "Taxa evolving in isolation on oceanic islands without competition or predators may not be able to adapt to rapidly changing conditions, such as the extensive climatic fluctuations of the Ice Ages or sudden competition or predation from introduced animals".
Thus, it is likely that permanent change in the cellular level of chaperones may result in negative fitness effects, especially in nature with its extensive environmental fluctuations.
In order to focus on the more extensive gene fluctuations between samples, further reductions in the number of genes used for some analyses were based on filtering out genes with low inter-sample variation.
On a regional scale, extensive population fluctuations in M. coquereli [ 123] are compensated by immigration from adjacent populations [ 124], but continuing fragmentation may put M. coquereli at risk of extinction from patches that are too remote to allow for recolonization.
We demonstrate a history of extensive genome fluctuation for this species and show that individual lineages could have acquired thousands of genes in the same period in which a 1% amino acid divergence accrues in the core genome.
Previous studies have noted an enrichment for enzymes/metabolism and organellar localisation in the human genome [ 53, 54] and the seed development process is naturally accompanied by extensive metabolic fluctuation [ 33, 55, 56].
In fact, bursts in the expression of single genes, due to intrinsic noise, can propagate to the expression of downstream genes generating extensive and correlated fluctuations (extrinsic noise).
It experiences a wide array of environmental conditions (e.g., temperature fluctuations), exhibits extensive phenotypic plasticity (Herreid and Kinney 1967; Berven 1982), and presents specific biochemical adaptations that help it survive freezing temperatures (Storey and Storey 1984).
Despite these extensive temporal and spatial fluctuations, the overall architecture of the monomeric mutant protein resembles that of wild-type GB1 and not the monomer unit of the domain-swapped dimer.
