Scientists have been able to prove Charles Darwin's Theory of Evolution - by sequencing pigeon DNA.
A study, led by researchers from the University of Utah and BGI-Shenzhen in China, has found the basic genetic traits that control diversity in pigeons.
This was done by mapping the genetic blueprint of the rock pigeon, one of the most common types of bird, from which Darwin said all pigeons were descended.
They also examined feral pigeons and racing birds to find connections between the breeds and to fill gaps in the relationship between the different types.
The pigeon's origins lie in the Middle East and the species captivated Darwin, with the father of evolution breeding them and using them to develop his theory of natural selection.
Michael Shapiro, one of the study authors, said: "Birds are a huge part of life on Earth, but we know surprisingly little about their genetics.
"We've shown a way forward to find the genetic basis of traits - the molecular mechanisms controlling animal diversity in pigeons.
"Using this approach, we expect to be able to do this for other traits in pigeons, and it can be applied to other birds and many other animals as well."
Trait evolved once and spread
The study, published in the journal Science Express, looked at how mutations give pigeons certain traits, such as feather head crests - present in all 350 species of rock pigeon.
Pigeons were domesticated around 5,000 years ago. The scientists sequenced the genomes of the rock pigeon, as well as fancy breeds and feral pigeons.
Shapiro said their findings strongly suggest Darwin was right to think all pigeons were related to the rock pigeon, as all the breeds sequenced were genetically similar.
By looking at a mutation shared by all crested pigeons, scientists were able to show that the trait evolved once and then spread to numerous types of pigeon through breeding.
After developing the blueprint for pigeons, the researchers analysed genomes of two feral pigeons living a great distance from one another.
Shapiro said: "Despite being separated by 1,000 miles, they are genetically very similar to each other and to the racing homer breed.
"Darwin used this striking example to communicate how natural selection works. Now we can get to the DNA-level changes that are responsible for some of the diversity that intrigued Darwin 150 years ago."