Assignment task: Multiple factors can influence both types of heritability.
Think simply and logically - what are some things that can influence genes? We've already talked about them. Population size - remember bottlenecks? Immigration/emigration, the influx or loss of (an) individual(s). Environmental disasters like hurricanes, floods, and earthquakes.
In your own words, define broad sense heritability and narrow sense heritability. Describe a specific factor where an event like immigration or a natural disaster affected heritability and the allele frequency.