Predators may depend on prey for food, but an increase in the number of prey animals does not bring a proportional increase in the number of predators, a new study has found.

The analysis, which appears in the journal Science, relies on data from more than 1,000 studies of animals in more than 1,500 locations worldwide. “Looking at this very large scale suggested a level of organization that was previously not recognized,” said Ian A. Hatton, a biologist at McGill University.

Dr. Hatton and his colleagues first set out to compare carnivores and herbivores in different ecosystems in Africa, like the Serengeti and the Kalahari. The researchers found a consistent pattern: Numbers of predators do not increase as rapidly as prey. The differences between the two populations are formulaic and predictable. Surprised by the finding, the scientists went on to look at ecosystems in other parts of the world.

In crowded settings, prey produce fewer offspring because of resource constraints. And because predators tend to target the young and the old, they have less to eat.