The amoeba is known to gather together in large "fruiting bodies" A species of amoeba - among the simplest life forms on Earth - has been seen "farming" the bacteria it eats.
When the bacteria become scarce, the Dictyostelium discoideum slime mould gathers up into a "fruiting body" that disperses spores to a new area.
Research described in Nature shows that a third of these spores contain some of the bacteria to grow at the new site.
Food management has been seen in animals including ants and snails, but never in creatures as simple as these.
The behaviour falls short of the kind of "farming" that more advanced animals do; ants, for example, nurture a single fungus species that no longer exists in the wild.
But the idea that an amoeba that spends much of its life as a single-celled organism could hold short of consuming a food supply before decamping is an astonishing one.
More than just a snack for the journey of dispersal, the idea is that the bacteria that travel with the spores can "seed" a new bacterial colony, and thus a food source in case the new locale should be lacking in bacteria.
D. discoideum is already something of a famous creature, having proven its "social" nature as it gathers together into a mobile, multicellular structure in which a fifth of the individuals die, to the benefit of the ones that make it into the fruiting body.
Researchers from Rice University in Texas, looking to study the amoebas further, happened across another, truly unique behaviour - discovered perhaps because the samples came from the wild, rather than grown in the laboratory.
"It was a bit of serendipty, really," Debra Brock, lead author of the Nature story, told BBC News.
"I had previously worked with them, looking at developmental genes. Not many people work with wild clones but I had started in a new lab and my advisers had a large collection of them, and I came with a bit of a different perspective."
Once Ms Brock spotted the amoebas' fruiting bodies carrying bacteria, she measured how many of the spores were responsible, finding that about a third of them traveled with their bacterial seeds.
The behaviour seems to be genetically built-in; clones of the "farmer" amoebas in turn developed into farmers, while clones of the "non-farmers" did not.
The bacteria form the basis of a food crop at the spores' new locations "To think of a single-celled amoeba performing something that you could consider farming, I think, is surprising," Ms Brock said.
"Choices like that are generally costly, so there has to be a pretty large benefit for it to persist in nature."
That is to say, the amoebas, in choosing not to consume all of the bacteria around them, are forced to make smaller fruiting bo
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