Do Insects Disperse Seeds?

Insects such as bees thrive off of jumping from one plant to another to extract nutrients. It would only make sense that these insects drop those seeds somewhere, right?

Insects are capable of carrying and dispersing seeds from plants. One key example of this process is the fact that ants carry and disperse seeds for use in their own nests.

The remainder of this article will explore exactly how insects obtain, carry, and spread the seeds of plants. We will explore this idea by looking at how different species carry out their respective processes of dispersal.

What Is Seed Dispersal?

Seed dispersal can be defined as the removal of seeds from plants for the purpose of relocation. This process influences insects, plants, animals, and the environment at large. The process of seed dispersal is crucial to the continuation of the plant species’ life cycle. 

How Does Seed Dispersal Benefit the Environment?

There are a number of potential benefits that the environment may gain from seed dispersal. One of these benefits involves seeds being protected from seed-eating animals that could prevent that plant species from being planted and grown in a new location. 

Another way that the environment can benefit from seed dispersal is the elimination of competition for land by plants of the same species. Thus, the likelihood that plants will compete over resources in a shared space is eliminated. 

Some insects, such as stick bugs, lay eggs that strongly resemble seeds. It is common that other insects will pick up these eggs and bring them back to their nests, where they are provided proper shelter from predators. 

Can Seeds Survive After Being Picked Up?

Seeds are capable of not only surviving but thriving after being dispersed by insects. Both insects and plants alike are capable of benefiting from their relationship. This process is known as insect-plant mutualism.

Insect-plant mutualism is just one way that seeds can travel across vast areas of land. Without the help of insects, seeds can be carried by wind or by animal-plant mutualism thanks to birds. When seeds are picked up by insects and carried away from the parent plant, their chance of survival increases significantly. 

Once the seed is dropped at its secondary location, it is capable of working its way below the surface of the earth. Once it is fully submerged below the surface of the earth, the seed is able to begin the germination process. Eventually, the seed would become a fully grown plant, and the cycle begins once again. 

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How Do Insects Carry Seeds?

In order to carry the seeds from one place to another, the insect must first determine what parts of the plant are safe to consume and which parts are the seeds. The most obvious way for insects to make this distinction is coloration. 

Other factors such as size and shape help the insects to distinguish between the plant and the seed. Additionally, these factors make it significantly easier for the insect to pick out the most useful parts of the plant.

Once the seed has been located, the insect uses its mouth to secure a grip on the seed. The remainder of the seed, or seeds, is transported back to the insect’s nest. Once the insect has returned to its nest, the excess food body is fed to larvae. Seeds that are too large or oddly shaped are typically left completely intact within the nest.

It is important to note that while the insect provides shelter and protection to the seeds during transportation, it is possible that seeds could be lost or damaged along the way. 

Who Benefits From Seed Dispersal?

Both the parent plant and the carrier of the seeds benefit from insect-plant mutualism. For the plant, its population is able to grow and thrive thanks to the insect acting as a carrier. Throughout the journey from the parent plant to the new location in which the seed will be dropped, the insect is providing shelter and protection to the seed.

For insects such as bees, pollination is one of the most important processes carried out by the entire hive. Pollination is the primary reason that bees come into contact with the parent plant.

Another way that plants benefit from the insect-plant relationship is the fact that carnivorous insects can eat other insects that may be harmful to the plant. While the plant is being protected from harmful insects, the carnivorous insect is gaining essential nutrients. 

Ants

Ants are considered one of the best examples of insects that are capable of carrying and dispersing seeds. There are five different ways by which ants, specifically, are able to disperse seeds. 

The fatty part of the seed, known as elaiosomes, is especially desirable to ants. These food bodies are an excellent source of nutrients such as sugars, amino acids, and fatty acids. A chemical found in this part of the seed, known as an attractant, stimulates the ant and promotes what is known as collecting behavior. 

One way that ants are able to disperse seeds occurs prior to the removal of the food body. This is achieved through the process of removing all parts of the plan that can be consumed as food. This food body is processed by the insect’s body and released as waste. It is common for some seeds to be relocated to refuse piles. 

The dispersal of seeds can also occur at the time in which the food body is being removed. At this stage, a significant amount of the seeds will be left behind by the ant. This is because the remaining clusters of seeds would be too large or heavy for a single ant to move from one place to another. 

The seeds may also be dispersed prior to the removal of the food body from the rest of the plant. There are a number of factors that could cause ants to abandon their nests, leaving behind piles of stored seeds. 

Bees

Bees are most commonly known for their ability to carry out a process known as pollination. Pollination is considered a form of seed dispersal since it involves useful parts of the plant being collected by the insect and carried to another location.

Bees are able to decide which plants have pollen on them because the bee can detect certain UV rays. Flowers that are blue or purple are most likely to possess these markings. 

The pollen or seeds of the plant collect on the bees’ legs. After pollination occurs at the site of the parent plant, the bee returns to its nest, dropping off small amounts of pollen along the way. 

Cross-pollination occurs when the bee flies from plant to plant, leaving bits of pollen on each plant. Pollen is capable of remaining attached to the bee for up to one kilometer. 

Conclusion

Insects are capable of picking up and dropping seeds by way of dispersion. The relationship between the parent plant and insect, in this situation, is known as insect-plant mutualism. In this relationship, both the plant and insect benefit in some way, thanks to their interactions.

Ants are an example of insects practicing seed dispersal. In this example, the insect, plant, and environment all benefit from the process. The ant is able to extract nutrients from parts of the plant while the seed itself is spared. This “new life” ensures that the plant species’ life cycle will carry on. 

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