What Makes Golden-Crowned Manakin Special? Scientists Discover First Hybrid Bird (Download PDF)

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Scientists have discovered the first known hybrid bird species in the Amazon rainforest - a golden-crowned manakin with yellow feathers. Such hybrid species among vertebrates are exceedingly rare.

Image of Golden-Crowned Manakin yellow feathers hybrid

Image of Golden-Crowned Manakin Yellow Feathers Hybrid

Image of Golden-Crowned Manakin yellow feathers hybrid

What is Hybrid Species?

  • 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.

  • Through a series of genetic and other tests researchers found that the golden-crowned manakin - first discovered in Brazil in 1957 but not seen again until 2002 - is in fact a hybrid species.

  • Hybrid plant species are very common but hybrid species among vertebrates are exceedingly rare

Details of Golden-Crowned Manakin

  • In case of Golden-Crowned Manakin 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.

  • Using the gathered genetic and feather samples over two separate field trips to Brazil researchers were able to sequence a large portion of the golden-crowned manakins 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 coalescent modelling to find that golden-crowned split off from its parental species around 180, 000 years ago when the two parental species originally mated.

  • Researchers found 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 4 million years ago, so these are all young birds by comparison

Where is Golden-Crowned Manakin Found?

  • The golden-crowned manakin is found in south-central Amazon Rainforest in 200 square kilometres in an area largely separated from snow-capped and opal-crowned wide rivers that the birds are reluctant to cross.

  • This isolation from parental species happened at some point during a past ice age when rainforest coverage contracted, and wide rivers formed natural barriers.

  • This geographic isolation was key- because there aren’t hybrids evolving as separate species in other areas where both parental species meet

What is Coalescent Modelling?

Image of what is Coalescent Modelling

Image of What is Coalescent Modelling

Image of what is Coalescent Modelling

  • Coalescent theory is a model of how gene variants sampled from a population may have originated from a common ancestor.

  • Coalescent theory assumes no recombination, no natural selection, and no gene flow or population structure, meaning that each variant is equally likely to have been passed from one generation to the next.

  • The model looks back in time, merging alleles into a single ancestral copy according to a random process in coalescence events.

- Published/Last Modified on: January 21, 2018

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