Some plants have come to rely so heavily on ants to spread their seeds about that they offer the insects a tasty treat in exchange for the dispersal service. Seeds of these species bear a lipid-filled structure called an elaiosome, whose sole function appears to be the attraction of ants. Here, Aphaenogaster fulva disperse bloodroot (Sanguinaria canadensis) seeds. Urbana, Illinois, USA
A number of plant species have come to depend on ants to disperse their seeds. To entice the ants, the seeds have a tasty, lipid-rich structure called an elaiosome at one end, and the ants carry the seed along when then take the elaiosome back to their nest. Here, Formica exsectoides mound ants have found the seeds of leafy spurge, an invasive pest plant whose spread might be facilitated by the ants. Wisconsin, USA
