A million years ago, the soundtrack to the mountains of East Africa’s “Island of the Sky” might have been very similar to what it is today. This is because a group of small colorful birds have been singing the exact same song for over 500,000 years, perhaps 1 million years.
Sunbirds are colorful, small nectar-eating birds that resemble hummingbirds and are common in Africa and Asia. They are “small gems that appear before you” and are senior author Lauri Bowie, a professor of integrated biology at the University of California, Berkeley and a curator at the University of California, Berkeley’s Museum of Vertebrate and Zoology. Said in a statement..
Tiny Sunbird (Cinnyris mediocris), Also known as the “Sky Island Sunbird”, it inhabits the tops of tall mountains in East Africa from Mozambique to Kenya. The peaks of these skyscrapers have isolated different populations or strains of this species from each other for tens of thousands to millions of years. However, many populations of Sunbirds on the sky islands are indistinguishable from each other, even though they do not interact at all.
Bowie and his team wondered if the bird song hadn’t changed over the years. To answer this question, researchers visited 15 separate empty islands in East Africa between 2007 and 2011 and recorded songs from 123 individual birds from 6 different Sunbird lines. Did.Then they developed a statistical method to analyze how Sunbird’s songs are sung. Evolved..
Indeed, some of these isolated groups are still singing the same song. This suggests that these songs have not evolved much during the thousands of years that these lines were separated. Researchers also analyzed the genetic differences between the populations so that the two populations of the longest isolated species had about the same song, while the other two populations isolated in the shorter time. I found that I had a very different song. ..
The team’s findings were amazing. Biologists usually expect bird calls to evolve and change over time in different populations. According to Bowie, the idea of rapid evolution of bird calls is likely to have come from studying birds in the Northern Hemisphere, where environmental conditions have changed many times over tens of thousands of years. Birds in the Northern Hemisphere are believed to have evolved new colors, songs, and behaviors to better adapt to new environments such as the presence or absence of glaciers.
However, the mountains of East Africa show little geological change, suggesting that Sunbird had no reason to evolve different feathers and songs. According to the statement, researchers concluded that birds and their songs could remain unchanged for millions of years until the birds evolved rapidly or pulsatingly due to changes in the environment. Accompanying video..
“Isolating humans often changes dialects. After a while, you’ll see where someone came from, and the songs are interpreted in the same way,” Bowie said. “Our paper shows that this is not always the case for birds. Even very unstable traits such as songs and feathers can cause long-term stagnation. “
Scientists are now continuing their research in East Africa to find out why some birds evolve new songs and others do not.
The findings were published in the journal on November 17th. Bulletin of the Royal Society B..
Originally published on Live Science.
These birds have been singing the same songs for literally a million years Source link These birds have been singing the same songs for literally a million years