A bird species that migrated from riverbanks in South America to the northern hemisphere were responsible for pollinating a plant species in South America. However, now it has become dependent on bird food supplied by local residents in bird feeders. Fewer and fewer birds stay in their northern habitat rather than migrate south. How will this affect gene flow?

Gene flow would decrease as a result of the alteration of migration patterns. Therefore, the variability of this species would decrease.

Explanation:

Gene flow refers to the transfer or introduction of genes from one population to another. Gene flow enables the introduction of new alleles, therefore increasing biodiversity.

The rate of gene flow between groups of species depends on different factors. For instance, gene flow increases with the ability of a species to move from one place to another and, at the same time, on the possibility of migrating species mating with resident species. This occurs not only with birds but even with humans, when they migrate from one country to another, which increases diversity and variability.

Therefore, if the migration patterns of birds that pollinate a plant species from South America is altered, then there would be less variability within this plant and also with this bird species.