Genetics affects speciation mostly via mutation caused due to adaptation and environmental conditions.
Explanation:
- The Speciation is defined as the evolution of a species into a distinct species. The cause of this could be several, and some of them could be environmental conditions, mutations, etc
- Environmental conditions include isolation of the species caused by mountain rise, river, flood etc. to survive they have to evolve or get adaptations to living in those conditions
- Mutation happens for many reasons, external factors can also cause the mutations to occur. It will also lead to speciation.