Final answer:
Evidence for the components of vertebrate hemoglobin arising from gene duplication can be seen in the presence of homologous genes coding for carbohydrates on the surfaces of red blood cells in amphibians and mammals, but not in fish. The synthesis of each chain of hemoglobin is controlled by specific genes, with vertebrates having multiple copies of α-genes and a single copy of β, γ, and δ genes. Common amino acid sequences in proteins and whole genome duplication events also support the concept of gene duplication as a mechanism for evolution in vertebrates.
Step-by-step explanation:
Evidence for the components of vertebrate hemoglobin arising from gene duplication can be seen in the homologous genes coding for the carbohydrates found on the surfaces of red blood cells in amphibians and mammals. These genes are not present in fish, suggesting a common ancestor for the ABO gene system at least 20 million years ago.
Furthermore, the synthesis of each chain of hemoglobin is controlled by specific genes. For example, the α chain is synthesized from α-genes, β chain from β-genes, and so on. Vertebrates have multiple copies of the α-genes but only one copy of the β, γ, and δ genes.
The presence of similar amino acid sequences in proteins across different species, such as histones and globins, also supports the idea of common ancestry. Additionally, the whole genome duplications that occurred during vertebrate evolution, resulting in quadruplication of the basic genome, including Hox genes, provide further evidence for gene duplication as a mechanism for evolution in vertebrates.