The transgenerational inheritance of lifespan is facilitated by the accumulation of repressive chromatin across generations.

Maternally experienced environmental stress leads to multigenerational inheritance of ethanol preference and an altered rewards pathway in Drosophila melanogaster.

In Caenorhabditis elegans histone methylation (H3K9me3) controls the synthesis of heritable small RNAs in a gene-specific manner and thus enables 'flagging' of newly-acquired genes.

The PRC2 Polycomb complex made in the mouse oocyte prevents transcriptional inactivation of the maternal X-chromosome in the early embryo.

H3K23me3 is a RNAi-mediated transgenerationally heritable heterochromatin mark in Caenorhabditis elegans.

Transient adaptation to environmental fluctuations in plants is mediated through discrete epigenetic changes.

Phosphate starvation in rice induces widespread, but transient, modulation of DNA methylation near stress responsive genes that is independent from the RNA-directed DNA methylation pathway.

Progeny can inherit parental experiences through altered brain chemistry.

rDNA copy number is shown to dynamically change during aging and through generations, and is actively maintained in male germline of Drosophila.

Evidence is mounting that environmentally-induced adaptive changes in phenotype can be transmitted across generations, but mechanistic gaps and theoretical concerns must be addressed to impact mainstream views of evolutionary adaptation.