Digger wasps make a short burrow for each egg, stocking it with food and returning a few days later to provide more. A new study reveals that mother wasps can remember the locations of up to nine separate nests at once, rarely making mistakes, despite the fact nests are dug in bare sand containing hundreds belonging to other females.

The paper is published in the journal Current Biology and is titled “Memory and the scheduling of parental care in an insect population in the wild.”

Mothers feed their young in age order, adjusting the order if one dies, and they can even delay feeding offspring that had more food at the first visit. Their intricate scheduling reduces the chance that offspring starve.