Epigenetics guides Bats rapid adaptation


The article "Natural epigenetic variation in bats and its role in evolution" by Zhang et al. (2016) discusses the potential role of epigenetic variation in the evolution of bats. The authors found that bats living in diverse environments show extensive epigenetic variation, which exceeds the corresponding genetic variance. This suggests that epigenetic variation may play a significant role in the adaptation of bats to their environment.

The Modern Evolutionary Synthesis (MS) states that evolution occurs through the process of natural selection acting on genetic variation. However, the discovery of epigenetic variation has challenged this theory, as epigenetic variation can also be inherited and can lead to phenotypic changes.

Epigenetic variation is changes in gene expression that are not caused by changes in DNA sequence. These changes can be caused by environmental factors, such as diet or stress, or by the actions of other genes. Epigenetic changes can be inherited from parents to offspring, and they can persist for multiple generations.

The authors of the article argue that epigenetic variation provides an additional pathway for environmental adaptation. They suggest that epigenetic variation can allow bats to rapidly adapt to changes in their environment, without having to wait for genetic changes to occur. This could be especially important for bats, which live in a variety of different environments.

The discovery of epigenetic variation has important implications for our understanding of evolution. It suggests that the MS may needs to be modified or bypassed to account for the role of epigenetic variation. Epigenetic variation could play a significant role in the evolution of many organisms, and it could help us to understand how organisms adapt to their environment.

Here are some additional thoughts on the role of epigenetic variation in evolution:

  • Epigenetic variation could be a major driver of evolution in rapidly changing environments.

  • Epigenetic variation could help organisms to adapt to new environments without having to wait for genetic changes to occur.

  • Epigenetic variation could be a source of new genetic variation, as epigenetic changes can sometimes be passed on to offspring.

  • Epigenetic variation could contribute to speciation, as it could lead to the development of new populations that are adapted to different environments.

The study of epigenetic variation is a rapidly growing field, and we are only beginning to understand its full implications for evolution. However, it is clear that epigenetic variation is a major player in the process of evolution, and it will continue to be an important area of research in the years to come.

Article snippets:

Natural epigenetic variation in bats and its role in evolution

When facing the challenges of environmental change, such as habitat fragmentation, organisms have to adjust their phenotype to adapt to various environmental stresses.

Recent studies show that epigenetic modifications could mediate environmentally induced phenotypic variation, and this epigenetic variance could be inherited by future generations, indicating that epigenetic processes have potential evolutionary effects

Bats living in diverse environments show geographic variations in phenotype,

We have also estimated the effects of genetic variance and ecological variables on epigenetic diversification. All three bat species have a low level of genomic DNA methylation and extensive epigenetic diversity that exceeds the corresponding genetic variance.

When facing challenges from environmental changes or stresses, organisms have to adapt to the changed environment by genetic mechanisms, physiological adaptability, phenotypic plasticity or moving to a new, more suitable area

The genetic changes may support abundant phenotypic variation in organisms for environmental adaptation, but they occur slowly and cannot keep pace with the rapidly changing environment

Recent studies have suggested that epigenetic modifications in eukaryotes could affect genetic expression and thus may mediate phenotypical variation in response to rapid and unpredictable environmental changes without genetic divergence

These environmentally induced epigenetic patterns may even be stably inherited by future generations (Grant-Downton and Dickinson, 2006; Jablonka and Lamb, 1998; Richards, 2006), which provides an additional pathway for environmental adaptation and produces a challenge to the Modern Evolutionary Synthesis

epigenetic process is another source of random variation in natural populations in addition to genetic variance

Differences in diet determine whether honeybee larvae develop into either sterile workers or reproductive queens by altering their genomic DNA methylation

bats may present an opportunity to explore the evolutionary potential of epigenetic variance in environmental adaptation

Nine populations of H. armiger comprising 45 females, nine populations of R. pusillus comprising 39 females and eight populations of M. fuliginosus comprising 47 females in total were selected to explore the natural epigenetic characteristics in bats

All three bat species investigated exhibit high levels of epigenetic polymorphisms

Greater individual epigenotypic variation contributes to the extensive methylation diversity within a population, which could support the ‘raw material’ for adaptive evolution

Epigenetic diversity of a similar extent to that found in these three bat species has been reported in plants

indicating that extensive intraspecific epigenetic variation and epigenetic structuring may be widespread in wild populations.

Greater epigenetic diversity may have evolutionary potential for wild populations

genome-wide methylation variation may compensate for the decreased genetic variation

The relationship between epigenetic and genetic diversity is a key aspect in epigenetic research because it determines the degree of phenotypic variation that can be explained by epigenetic effects alone or the significance of meiotic transmission of epigenetic variance

the large variation in DNA methylation in Arabidopsis thaliana plants is not correlated with their genetic divergence

the significant relationship suggests that most of the methylation variation among bat populations may belong to the obligatory or facilitated epigenetic variation type, which indicates that correlated genetic–epigenetic variation may be a possible pathway for the evolution of bat populations

The extensive DNA methylation polymorphisms and diversity in bat populations significantly exceed the corresponding differences in genetic profiles

suggesting that at least a part of methylation variation is independent of genetic divergence or can be identified as pure epigenetic variation.

populations living in diverse environments exhibit extensive variation in genome-wide DNA methylation.

Ecological factors covarying across geographical locations may have a greater impact on DNA methylation of bats

environment-induced methylation patterns in bats may be reversible when the normal environment is restored.

Heritable epigenetic marks pose a serious challenge to the Modern Evolutionary Synthesis, which assumes that DNA sequence variance is the only heritable variation in natural populations

Genetic changes could not provide an effective phenotype for bats to adapt to environmental changes rapidly, and it is therefore necessary to consider another explanation.

Epigenetic cues, such as DNA methylation, could mediate phenotypic variation in response to environmental changes without genetic divergence, and may provide insight into the mechanisms of environmental adaptation of bat populations.

Their greater epigenetic polymorphisms and significant epigenetic structures exhibit extensive methylation diversity within and among populations and individuals, as also found in plants, indicating that the extensive individual epigenotypic variations may be evolutionarily significant to wild populations.



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