Final answer:
Gene duplications are copies of a gene that result from duplication within the lineage of a species. These duplications can lead to the emergence of new functions for proteins.
Step-by-step explanation:
When a segment of DNA is duplicated within the lineage of a species, it creates copies of a gene. These copies are known as gene duplications. Gene duplications can result in multiple copies of genes in the chromosome, providing opportunities for evolutionary changes and the emergence of new functions for proteins.