|New mutation in DNA|
[Image source: http://www.topnews.in/health/genetic-mutation-may-have-allowed-great-expansion-early-humans-216902]
In their model, a mutated copy of an existing gene first gains a weak function next to its primary function. If conditions change, the secondary function might become increasingly more important.
The researchers tested their model in the bacterium Salmonella and observed changes for over 3.000 generations.
The new model aims to explain how new functional genes emerge (given that cells have mechanisms in place to constantly remove mutations).
Read more here: Evolution of new genes captured