During our hard times, many of us turn to family and develop closer ties and seek comfort. So too with amoebas.

New research shows some of these single-celled organisms tighten family bonds and cooperate when food is in short supply.

The research, published this week in the journal PLoS Biology, shows how one amoeba species can discriminate genetically similar individuals, and how an incredibly simple life-form can display some sophisticated, social behaviors. (Not only is an amoeba a single cell, it reproduces asexually. So one parent cell divides into two daughter cells, which can continue to divide and produce more amoebas.)

"These single cells aggregate based on genetic similarity, not true kinship," said researcher Gad Shaulsky, professor of molecular and human genetics at Baylor College of Medicine in Houston. Shaulsky added that this demonstrates a inequity between "self" and "non-self" that is similar to that seen in the immune systems of higher organisms.

Amoeba community called Dictyostelium discoideum, this amoeba species generally keeps to itself when living in a healthy environment with enough grub.

But when food supplies run low, the free-living organisms clump together into a community of individuals. The result is a multi-cellular organism. Each amoeba takes on one of two roles in this organism: They either become spores, which can survive and reproduce, or they die and the dead cells forms stalks that lift the spores above the ground to increase the chances the spores will disperse to more favorable environments.

Only cells that form spores can pass on their genetic information to future amoebas. So the preferred position is spore. About 20 percent of the cells, however, do turn into stalks.