Hybrid swarm

Such population are highly variable, with the genetic and phenotypic characteristics of individuals ranging widely between the two parent types.

[6] When introgression has occurred, there will be a high level of diversity in alleles near the vicinity of the hybrid swarm.

[8] In one study of a young hybrid swarm of these two species, the population was found to be composed of the parent species, F1 generation offspring, and backcrosses with the water aven, but no backcrosses with the wood aven and no F2 generation, which would result from self-pollinating F1s.

[10] One example of an invasive hybrid swarm occurs among shiners in the upper Coosa River.

[11] The population has expanded its range over time, moving both downstream and upstream while the proportion of hybrid individuals in the system is increasing.

A red-bellied paradise flycatcher ( Terpsiphone rufiventer ) found in the gallery forests of Abuko, The Gambia (where many of the T. rufiventer are part of a hybrid swarm with T. viridis ).