Toronto, Dec 26 (IANS): Taking a closer look at genetics and feathers, scientists have found that the golden-crowned manakin is in fact a hybrid species, making it the first such bird species known to be living in the Amazon rainforest.

The bird was first discovered in Brazil in 1957, but it was not seen again until 2002.

"While hybrid plant species are very common, hybrid species among vertebrates are exceedingly rare," said senior author of the research Jason Weir, Associate Professor at University of Toronto Scarborough in Canada.

A hybrid species forms when two parental species mate to produce a hybrid population, which then stops being able to freely interbreed with the parental species.

In this case, the two parents are the snow-capped manakin, named for its bright snowy-white crown feathers, and the opal-crowned manakin, named for its brilliant iridescent crown feathers.

For the study, to be published in a forthcoming issue of the journal Proceedings of the National Academy of Science, the researchers gathered genetic and feather samples over two separate field trips to Brazil.

They were then able to sequence a large portion of the golden-crowned manakin's genome including 16,000 different genetic markers, finding that about 20 per cent of its genome came from the snowy-crowned, and about 80 per cent came from the opal-crowned.

The researchers also used something called coalescent modelling to figure out at what point the golden-crowned split off from its parental species.

They determined it was around 180,000 years ago when the two parental species originally mated, and that both parental species diverged from a common ancestor about 300,000 years ago, making all three very recent birds by Amazon rainforest standards.

"Most Amazon bird species diverged from their most recent relative around 1.5 to four million years ago, so these are all young birds by comparison," Weir said.

The male golden-crowned has unique yellow crown feathers that are much duller than its parental species, the study said.

While hybrids of two species do occur in nature, in most cases they won't develop unique characteristics to become its own separate species, Weir said

"This is what makes the golden-crowned manakin such a novel animal," he added.