Bruchid beetles eat the seeds produced by palo verde trees. Palo verde trees are native to Arizona's Sonoran Desert. They also are common in landscaped areas including parks, schoolyards and backyards.

Female bruchid beetles lay their eggs on palo verde seedpods. After they hatch, beetle larvae eat the seeds, pupate and emerge as adult beetles through little holes they create in the seed pods.

Plants are at the base of food webs and any change in a plant community can have an impact on all organisms that feed higher up the food web.

We don't really know whether palo verde trees growing in a city have different seedpod development as compared to those in the Sonoran Desert.

We also don't know how (or even if!) urbanization of the trees has changed the interaction between bruchid beetles and palo verde trees.

There might be many reasons that urban trees will grow differently than desert trees. For example, trees in yards and parks may receive more water and fertilizer which could increase the number of seeds produced.

Whether or not a seed will be eaten by a beetle depends on many different things. If a female beetle finds a seed, it must lay an egg on it, and then the beetle larvae must be able to eat the seed and survive. All these factors could be different in the city versus the desert. For example, the city seeds might be more or less attractive to the beetle, just as food prepared in different ways might be more or less appealing to you. Even if the beetle likes the seed the larva may not be able to survive feeding on it. For example a particular seed might be too small or too tough to eat.

CAP LTER ecologists are interested in the impact humans have had on native plants growing in cities and the insects that feed upon them. Your investigations might contribute to this understanding.

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