This is an example where each function you know, became optimized, but there are ways, there are reasons
why gene duplication can also create nothing new, whatsoever.
The genomic data provides a strong evidence from DNA level to illustrate
why Chinese alligator can hold its breath under water for long periods of time, such as the
duplication of the bicarbonate - binding hemoglobin
gene, positively selected energy metabolism, and others.