What does the term 'semelparous' refer to in evolutionary biology?

The term 'semelparous' in evolutionary biology refers to an organism that reproduces only once in its lifetime, followed by death. This reproductive strategy is characterized by producing a large number of offspring in a single event, which may enhance the likelihood of survival for at least some of those offspring in environments where adult survival is uncertain or conditions are especially harsh after reproduction. Examples of semelparous species include certain types of salmon and annual plants that produce their seeds once and then die. This strategy contrasts with other reproductive strategies like iteroparity, where organisms reproduce multiple times throughout their lives, allowing them to spread their reproductive efforts over different breeding seasons.