Globin 1 and globin 2 genes of insects are understood to have diverged approximately 170 million years ago, through duplication, from a common globin gene ancestor. The two genes that code for haemoglobin have conserved regions; oxygen-binding and heme- regions. Globin 2 gene has lost the intron region that is still present in the globin 1 gene. The percentage divergence is 7.2% with 20 varying nucleotides.
