Final answer:
Homologous genes across different species, known as orthologs, evolved from a common ancestor and usually retain similar functions. These genes provide insights into evolutionary relationships, such as the close genetic similarity between humans and chimpanzees.
Step-by-step explanation:
The two homologous genes found in different species that evolved from the same gene in a common ancestor are known as orthologs. These genes have diverged after a speciation event, meaning they are found in different species, but still retain similar functions. This is in contrast to paralogs, which are homologous genes that have evolved to have different functions within the same organism due to duplication events.
Understanding the concept of homologous genes is crucial in deciphering the evolutionary history of species. For example, the genetic code's homologous characteristic unites all species and points to a common ancestor in the deep past. Additionally, modern technology allows scientists to compare genes across species to determine evolutionary relationships, such as the significant genetic similarities found between humans and chimpanzees.