Seeds Can Inherit Warnings

Some studies suggest plants can pass stress-primed defenses to offspring. If a parent plant faces drought, salt, or heavy herbivore attack, its seeds may start life with defensive genes more ready to activate.

This is often described as epigenetic memory: chemical marks change how DNA is read without rewriting the DNA sequence. It is promising, but the strength and durability of those effects vary by species and condition.

Tobacco plants attacked by caterpillars produce seeds with upregulated defense genes. The offspring have never met a caterpillar, yet they already make higher levels of defensive chemicals — survival information handed down without a single nerve cell to carry it.