Seed Dispersal

Fruits and seeds contain the genetic material to produce new plants. Many “seeds” such as dandelions, burrs, and peas are really fruits, but are commonly called seeds.

Most plants produce an abundance of seeds, but only a few usually grow into adult plants. Even fewer seeds would mature if seeds were not dispersed away from the parent plant. A seed dropped directly underneath a plant may have difficulty growing, because the parent plant, in the process of ensuring its own survival, often deprives the new plant of sunlight or minerals needed for growth. Some plants even produce chemicals that prevent new plant growth in the immediate area.

Most land plants are anchored to the ground; they cannot move around to distribute their seeds. A few plants have mechanisms for scattering their seeds, but most plants simply drop their seeds.

Adaptations are features of organisms that help them to survive and reproduce. One of the adaptations enabling plants to produce new plants is a mechanism for distributing seeds and fruits to other sites with more favorable growing conditions. Exploding cucumbers, drifting dandelions, sticky foxtails, and winged maple fruits are examples of different seed or fruit dispersal mechanisms. In this activity, participants are challenged to modify dried beans or peas so that they could be dispersed.

Outdoor Biology Instructional Strategies (OBIS) is an outdoor program that offers young people fun and challenging opportunities to investigate ecological relationships in their local environment. OBIS was developed in the 1970s at the Lawrence Hall of Science to help adults (teachers, parents, community leaders) take young people outdoors to experience ecological principles in their local area. We have made several of the original 97 OBIS activities available digitally. These activities, which increase environmental awareness, can be used individually or in combination. These simple experiences then act as a gateway for children and adults to explore and understand their local environment.