Researchers have identified a family of small molecule signals that controls population density, sensing and mating behavior in the way worms communicate.

Caltech researchers found that nematodes, also known as roundworms whose parasitic cousins include hookworms, whipworms and trichinas, secrete ascarosides to control the social behavior of grouping together.

The study’s authors said the identification of specific ascarosides as aggregation signals “reveals unexpected complexity of social signaling,” in the worms of the species C. elegans.

The discovery is considered an important breakthrough that could be very important to the fields of biomedicine and agriculture, scientists said.

Researchers also noted that about a fourth of the world’s human population is infected with some type of parasitic nematode that survives by living inside a host and attacking it internally. Worms also attack plants and animals. The new findings could lead to ways to eliminate them by a chemical that can “attract them in order to kill them more efficiently,” Jagan Srinivasan, a senior research fellow in biology at Caltech and lead author of the study said in a statement.

"We're starting to get a hold on the chemical 'alphabet' that makes up these words, which have different meanings in different social contexts," Jagan said.

Researchers found that one class of chemicals encourages worm-to-worm company, while another set of compounds consecutively keeps other worms away.

Scientists suggest that the behavior is meant to attract only a certain number of worms when starting a new colony, just enough to find a share food. A colony cannot thrive with too many worms, but worms would call on a large group if there is a large food source, like a big piece of fruit.

The study also found that just the tiniest alteration of a chemical can totally change the meaning. Researchers compared this characteristic with the intonation in the Chinese language in which the smallest difference can completely change the meaning.

"Understanding the worm's language is just a first step," said Srinivasan. "We hope that by learning more about how social recognition occurs in the worm nervous system, we can eventually provide insights into how the human brain encodes social information, too."

Scientists plan to explore how the nervous system of the worm senses and organizes the different compounds.