When it comes to extreme adaptations, the Burmese python is a shining example of a species that can evolve highly specialized functions in order to survive. The source of their ability to evolve so rapidly and perform such feats as organ manipulation? It's all in the genome, says a new study.

"One of the fundamental questions of evolutionary biology is how vertebrates with all the same genes display such vastly different characteristics. The Burmese python is a great way to study that because it is so extreme," said Todd Castoe, an assistant professor of biology at The University of Texas at Arlington College of Science and lead author of the study published in the Proceedings of the National Academy of Sciences.

Burmese pythons, like many large snakes, ingest prey many times their size. In order to accommodate a huge animal, a Burmese python can increase its metabolism and the mass of vital organs like the heart, liver, small intestine, and kidneys by 35 percent to 150 percent within 24-48 hours. The python's organs and metabolism then return to normal in a few days. According to the scientists involved in the study, this is one of the most extreme examples of evolutionary adaptation.

In order to better study the driving forces behind such adaptation, the group of scientists involved in the study ended up compiling the first complete and annotated snake genome sequence ever.

"The Burmese python has an amazing physiology. With its genome in hand, we can now explore the many untapped molecular mechanisms it uses to dramatically increase metabolic rate, to shut down acid production, to improve intestinal function, and to rapidly increase the size of its heart, intestine, pancreas, liver and kidneys," said Stephen Secor, associate professor of biological sciences at the University of Alabama and a co-author on the paper.

"The benefits of these discoveries transcends to the treatment of metabolic diseases, ulcers, intestinal malabsorption, Crohn's disease, cardiac hypertrophy and the loss of organ performance."

Typical evolutionary theory holds that gene expression is the primary driving force behind such extreme changes. The new study, however, asserts that protein adaptation and changes in the structure of the genome itself are also key factors.

Burmese pythons are one of the largest snake species in the world, and typically grow up to 12 feet long in the wild.