Predator-Prey Equations Govern Gang Territories

The Lotka-Volterra equations describe population dynamics between competing species. Criminologists have now shown they also describe gang turf boundary formation and violence hot spots. Evelyn Lamb reports

Illustration of a Bohr atom model spinning around the words Science Quickly with various science and medicine related icons around the text

Join Our Community of Science Lovers!

The same mathematical models used to study the hunting range of lions have many other applications—they describe the flight patterns of honeybees. And now researchers say these math models can help explain the stability of gang territories and patterns of between-gang violence. The work is in the journal Criminology. [Jeffrey Brantingham et al., "The Ecology of Gang Territorial Boundaries"]

Researchers used the models to draw new maps of gang territories in East L.A. What are known as the competitive Lotka-Volterra equations describe population dynamics between species competing for resources. They take into account the effect each population has on the other.

The researchers generated maps of gang territories using the Lotka-Volterra equations rather than police reports or urban geographical features. After creating maps, researchers analyzed data about between-gang shootings and found that violence clusters along the gang boundaries predicted by their model.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


The researchers think that their work also demonstrates that a gang’s turf forms in part based on competitive interactions with other gangs. The hope is that understanding patterns of between-gang violence can help police prevent more of it.

—Evelyn Lamb

[The above text is a transcript of this podcast.]

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe