Heritable Adaptation and Fitness Costs in Killifish (Fundulus Heteroclitus) Inhabiting a Polluted Estuary

Abstract

Adaptation to contaminants in the environment has been studied extensively in microbes, insects, and plants, and increasing evidence suggests that certain vertebrate populations as well are evolving in response to pollution. Here, we show that F1 and F2 laboratory‐raised offspring of killifish (Fundulus heteroclitus, also known as mummichog) from a highly contaminated site on the Elizabeth River (Virginia, USA) are more resistant to the toxicity of Elizabeth River sediments than are offspring of reference site killifish. This resistance is more marked in the F1 than in the F2 generation, but it remains significant in the F2 generation, indicating that the resistant phenotype in the feral Elizabeth River killifish is based on both genetic and nongenetic mechanisms. In addition, both the F1 and F2 generation offspring of the Elizabeth River killifish are more susceptible to other stressors, both anthropogenic (photoenhanced toxicity) and natural (hypoxia), suggesting that the changes that have conferred resistance to the toxicity of the Elizabeth River sediments carry a cost of reduced fitness in other contexts. Corresponding Editor: J. E. McDowell.

Dynamics of epigenetic phenomena: intergenerational and intragenerational phenotype ‘washout’

“…2). Evidence for intragenerational washout at the molecular level also exists in the killifish (Fundulus heteroclitus), where a refractory CYP1a phenotype potentially acquired through germline-dependent epigenetic effects are progressively lost during larval development Meyer and Giulio, 2003) and fade out over time within the F 1 generation Before leaving the topic of intragenerational epigenetic effects, consider the medically oriented view of the concept of intragenerational wash-in. If one views a disease that develops through non-genetic mechanisms as an intragenerational epigenetic effect then, almost by definition, as the disease progresses, the modified (diseased) phenotype is 'washing in'.…”

Epigenetics and transgenerational transfer: a physiological perspective

“…These maternally derived factors can have a significant impact on offspring physiological phenotype (i.e. immunological capacity, growth and development, cardiovascular function and toxicant resistance) in a wide range of animals (Munkittrick and Dixon, 1988;Meyer et al, 2003;Weaver et al, 2004;Groothuis et al, 2005;Sellin and Kolok, 2006;Groothuis and Schwabl, 2008;Ho, 2008;Moreno et al, 2008;Romano et al, 2008;Hasselquist and Nilsson, 2009 (Ho, 2008). Metabolic rate, however, was not affected (Ho, 2008).…”

Propensity to metal accumulation and oxidative stress responses of two benthic species (Cerastoderma edule and Nephtys hombergii): are tolerance processes limiting their responsiveness?

“…In turn, this ability may allow a prevalence of the 60 most well-adjusted specimens (Meyer and Giulio 2003), which could lead to a decrease 61 in the biodiversity due to the extinction of the less adjusted ones (Lotze et Metals are recognized as long-lasting pollutants in estuarine systems, frequently 72 potentiating the occurrence of biological adjustments in the exposed organisms. 73…”