Some ants rush to rescue others while their nestmates do nothing

Some ants rescue trapped nestmates, and differences in nervous-system gene activity may help explain why individuals respond differently.

Ant colonies depend on workers doing different jobs, but those workers do not always react the same way to the same event.

One striking example is rescue behavior , when an ant digs, pulls, or bites at restraints to help free a trapped nestmate.

Some workers help, while others come close and do nothing.

A new study of the desert ant Cataglyphis nigra suggests that this difference is linked more closely to gene activity in the nervous system than to body size, brain size, or stored energy.

Rescue costs time and energy, can expose the helper to danger, and gives no immediate direct reward. Yet it can protect related members of the colony .

Professor Susanne Foitzik of Johannes Gutenberg University Mainz ( JGU ) worked on the project.