Dispersal vs Migration: Difference and Comparison

Key Takeaways

1. Definition: Dispersal is the movement of individuals away from their birthplace, while the migration is the regular movement between locations.
2. Distance and Patterns: Dispersal can be short or long-range, while migration involves longer distances and follows specific routes.
3. Purpose and Adaptations: Dispersal aids in colonization and gene flow, while the migration is driven by factors like resources or breeding, with specific adaptations for long-distance movement.

What is Dispersal?

Dispersal is when an individual moves away from their birthplace to settle in a new place or area. Dispersal is a natural phenomenon followed by various species, including plants, microorganisms, and animals. This phenomenon can happen for multiple reasons, such as water, wind, or any other type of transport medium, and other forms of active transport by any organism itself.

This phenomenon is quite an important feature that helps the population increase their new habitat and genetic diversity. It helps to avoid inbreeding and decline competition.

Dispersal has negative consequences that may affect the environment, including the prominent reason behind introducing a few invasive species and diseases. Some human activities, like fragmentation and human destruction, may disrupt dispersal patterns and restrict organisms’ ability to colonize new areas.

What is Migration?

Migration is when an individual makes a seasonal movement between two or more areas. Migration is also said to be a natural phenomenon depicted by a few organisms, mainly animals, who may travel from one place to another. This phenomenon is associated with seasonal changes. For example – flamingo birds come to India during their breeding season.

This phenomenon is very complex and is affected by many external factors like – the availability of water and food, change in temperature, and animals’ or organisms’ mating behaviour. This process can happen for long distances and includes many individuals. This phenomenon can occur over multiple places, such as – water, land, or air, and may involve a variety of locomotion, such as – flying, swimming, or walking.

The positive aspect of this process is that animals or organisms can access different resources unavailable in their usual or regular habitat. For example – birds migrate from winter to warmer climatic conditions to find availability of food and water.

Difference Between Dispersal and Migration

1. Dispersal is defined as when an individual move away from their birthplace. In contrast to this, Migration is defined as when an individual makes a seasonal movement between two or more areas.
2. The distance covered in the case of dispersal is quite a short distance. But if we compare it on the other hand, the distance covered in the case of Migration is long distances.
3. The type of movement is random in the case of dispersal, whereas comparatively, on the other hand, the kind of movement is planned in the case of Migration.
4. The purpose behind dispersal is for inbreeding to find a new habitat or to avoid competition. In contrast, comparatively, on the other hand, the purpose behind Migration is for better breeding and feeding conditions.
5. Dispersal happens in any direction, whereas Migration is said to occur between two specific points.
6. In dispersal, there is no specific timing of the occurrence. On the other hand, Migration primarily happens at seasonal or regular intervals.
7. The behavior expressed in dispersal is independent or solitary. At the same time, the behavior depicted in Migration is group-oriented or solitary.
8. Dispersal leads to the increased colonization of new habitats and genetic diversity. On the other hand, Migration enables successful reproduction and survival in various conditions.

Comparison Between Dispersal and Migration

Parameter of Comparison	Dispersal	Migration
Definition	When an individual move away from their birthplace	When an individual makes a seasonal movement between two or more areas
Distance Covered	Short distances	Long distances
Type of Movement	Random	Planned
Purpose	Inbreeding to find a new habitat or to avoid competition	For better conditions of breeding and feeding
Direction	Any direction	Between two specific points
Timing	Any time during the year	Seasonal or regular
Behaviour	Independent or solitary	Group-oriented or solitary
Effect on Population	Increases colonization of new habitats and genetic diversity	Enables successful reproduction and survival in various conditions

References

1. https://www.annualreviews.org/doi/pdf/10.1146/annurev.en.07.010162.001255
2. https://www.cabdirect.org/cabdirect/abstract/19690501815