Environmental change can critically affect the lifestyle, reproductive success, and life span of adult animals and their for generations. Klosin et al. showed that in the nematode worm Caenorhabditis elegans , exposure to high temperatures led to expression of endogenously repressed copies of genes—sometimes called “junk” DNA. This effect persisted for >10 generations of worms. The changes in chromatin occurred in the early embryo before the onset of transcription and were inherited through eggs and sperm.
Science , this issue p.