Bacteria offers clue to how birds got their wings

Using bacteria, an international team of evolutionary biologists has shed some light on how the birds got their wings.

The University of Oxford study, which involved collaboration with researchers from the University of Zurich, showed that acquiring duplicate copies of genes can provide a 'template' allowing organisms to develop new attributes from redundant copies of existing genes.

Gene duplication has been proposed as playing a key role in innovation since the 1970s, but these findings add important empirical evidence to support this theory.

Professor Craig MacLean said: "The appearance of novel traits, such as wings and flowers, has played a key role in the evolution of biological diversity. However, it is usually difficult to understand the actual genetic changes that drive these evolutionary innovations. We have taken advantage of a simple bacterial model system, where bacteria evolve the ability to eat new food sources, to overcome this obstacle."

The researchers allowed 380 populations of Pseudomonas aeruginosa bacteria to evolve novel metabolic traits such as the ability to degrade new sugars. This gave the researchers the opportunity to witness evolution happening in real-time.

Professor MacLean added that the key insight of the study is that having redundant copies of genes provides bacteria with a template for evolving new traits without sacrificing existing traits. In other words, redundant genes allow bacteria to have their cake and eat it.

He added that these findings provide important empirical evidence to support the role of gene duplication in evolutionary innovation, and they suggest that it may be possible to predict the ability of pathogenic bacteria to evolve clinically important traits, such as virulence and antibiotic resistance.

The study is published in the journal PLOS Genetics.