Nav: Home

Song experiments reveal 21 possible new tropical bird species

September 13, 2017

Birds often choose their mates based on song, making it a key factor in separating species. However, analyzing spectrograms can only tell us so much--the characteristics that birds hone in on when identifying potential mates may not be the same ones scientists notice in audio recordings. A new study from The Auk: Ornithological Advances uses field experiments to "ask the birds themselves" and uncovers as many as 21 previously unrecognized species.

Benjamin Freeman of the University of British Columbia and Graham Montgomery of Cornell University compared these two methods--analysis in the lab and experiments in the field--for 72 pairs of related but geographically separated bird populations in Costa Rica, Panama, and Ecuador. In addition to analyzing more than a thousand song recordings for seven variables, they used playback experiments to test birds' real-world reactions to recordings of their relatives, observing whether or not they approached the speaker. Their results show that when the divergence between the characteristics of the recordings is high, birds consistently fail to recognize recordings of their relatives in the field, but when divergence is low, birds' discrimination is much less consistent. In other words, analyzing recordings can't accurately predict how birds will act when presented with songs just slightly different from their own.

Many pairs that failed to recognize each other are currently categorized as members of the same species, suggesting that current taxonomy does not reflect actual bird behavior when it comes to song. Freeman and Montgomery propose that 21 such pairs should be recognized as separate species based on song discrimination and that playback experiments should be the standard for assessing whether song divergence between populations is a barrier to interbreeding. "It is abundantly clear to anyone familiar with the amazing diversity of Neotropical birds that there are many cases where populations that sing very different songs are classified as the same species," says Freeman. "These populations look the same--they have similar plumage and are similar in size and shape--but assuming that populations that sing differently tend not to interbreed, this means that species-level diversity in the Neotropics is underestimated."

"Playback experiments between geographically isolated taxa provide key data on how populations might perceive each other in terms of 'same' or 'different' if they were in actual contact," according to Louisiana State University's J.V. Remsen, an expert on Neotropical birds who was not involved in the research. "Hopefully, this pioneering study will catalyze a wave of similar studies around the globe as a way to approach the always-thorny problem of species limits in these birds."
-end-
"Using song playback experiments to measure species recognition between geographically isolated populations: A comparison with acoustic trait analyses" is available at http://www.bioone.org/doi/full/10.1642/AUK-17-63.1.

About the journal: The Auk: Ornithological Advances is a peer-reviewed, international journal of ornithology that began in 1884 as the official publication of the American Ornithologists' Union, which merged with the Cooper Ornithological Society in 2016 to become the American Ornithological Society. In 2009, The Auk was honored as one of the 100 most influential journals of biology and medicine over the past 100 years.

American Ornithological Society Publications Office

Related Birds Articles:

Birds become immune to influenza
An influenza infection in birds gives a good protection against other subtypes of the virus, like a natural vaccination, according to a new study.
Even non-migratory birds use a magnetic compass
Not only migratory birds use a built-in magnetic compass to navigate correctly.
When birds of a feather poop together
Algal blooms deplete oxygen in lakes, produce toxins, and end up killing aquatic life in the lake.
Birds of a feather mob together
Dive bombing a much larger bird isn't just a courageous act by often smaller bird species to keep predators at bay.
Monitoring birds by drone
Forget delivering packages or taking aerial photographs -- drones can even count small birds!
The color of birds
New research provides insight into plumage evolution.
Migrating birds speed up in spring
It turns out being the early bird really does have its advantages.
Birds on top of the world, with nowhere to go
Climate change could make much of the Arctic unsuitable for millions of migratory birds that travel north to breed each year, according to a new international study published today in Global Change Biology.
City birds again prove to be angrier than rural birds
The researchers' observations shed light on the effects of human population expansion on wildlife.
Teaching drones about the birds and the bees
Unmanned Aerial Vehicles (UAVs) of the future will be able to visually coordinate their flight and navigation just like birds and flying insects do, without needing human input, radar or even GPS satellite navigation.

Related Birds Reading:

The Genius of Birds
by Jennifer Ackerman (Author)

An award-winning science writer tours the globe to reveal what makes birds capable of such extraordinary feats of mental prowess
 
Birds are astonishingly intelligent creatures. According to revolutionary new research, some birds rival primates and even humans in their remarkable forms of intelligence. In The Genius of Birds, acclaimed author Jennifer Ackerman explores their newly discovered brilliance and how it came about.

As she travels around the world to the most cutting-edge frontiers of research, Ackerman not only tells the story of the recently uncovered... View Details


National Geographic Backyard Guide to the Birds of North America (National Geographic Backyard Guides)
by Jonathan Alderfer (Author), Paul Hess (Author)

Essential for the millions of Americans who watch and feed birds in their backyards—whether experienced birders or new birding enthusiasts—from the experts at National Geographic and co-author of the popular and perennial best seller Field Guide to the Birds of North America.
 
No matter where you live—in the country, city, a high-rise or house—this handy guide will quench your curiosity about the feathered creatures in your midst. It features 150 of the most common and interesting birds likely to be observed at backyard feeders, nesting nearby or just migrating... View Details


National Geographic Field Guide to the Birds of North America, 7th Edition
by Jon L. Dunn (Author), Jonathan Alderfer (Author)

This fully revised edition of the best-selling North American bird field guide is the most up-to-date guide on the market. Perfect for beginning to advanced birders, it is the only book organized to match the latest American Ornithological Society taxonomy.

With more than 2.75 million copies in print, this perennial bestseller is the most frequently updated of all North American bird field guides. Filled with hand-painted illustrations from top nature artists (including the ever-popular hummingbird), this latest edition is poised to become an instant must-have for every serious... View Details


The Thing with Feathers: The Surprising Lives of Birds and What They Reveal About Being Human
by Noah Strycker (Author)

An entertaining and profound look at the lives of birds, illuminating their surprising world—and deep connection with humanity.
 
Birds are highly intelligent animals, yet their intelligence is dramatically different from our own and has been little understood. As we learn more about the secrets of bird life, we are unlocking fascinating insights into memory, relationships, game theory, and the nature of intelligence itself.

The Thing with Feathers explores the astonishing homing abilities of pigeons, the good deeds of fairy-wrens, the influential flocking... View Details


Extreme Birds: The World's Most Extraordinary and Bizarre Birds
by Dominic Couzens (Author)

Extreme Birds is a photographic showcase of 150 birds at the extremes of nature. It reveals nature's ingenuity and sometimes its sense of humor. The species in this book were chosen for their extraordinary characteristics and for behaviors far beyond the typical. They are the biggest, the fastest, the meanest, the smartest. They build the most intricate nests, they have the most peculiar mating rituals, they dive the deepest and they fly the highest. These are the overachievers of the avian world.

Some examples:

Most skilled nest builder: The tiny... View Details


Backyard Birds (Field Guides for Young Naturalists)
by Karen Stray Nolting (Author), Jonathan Latimer (Author), Roger Tory Peterson (Illustrator)

Field guides for young naturalists backyard birds series is designed with the beginner in mind. Features the original art of celebrated naturalist roger tory Peterson; incorporates the Peterson identification system, the most effective method for bird identification; and uses a straightforward design. This series makes field guides accessible and appealing to children. Paperback; 48 pages trim. Age range: 8-12 years, grade range grades 4-6. Measures 5-inch width by 8.5-inch length. View Details


Living Bird: 100 Years of Listening to Nature
by Gerrit Vyn (Author), Cornell Lab Of Ornithology (Author)

NEW YORK TIMES BESTSELLERForeword by Barbara KingsolverOver 250 images by acclaimed wildlife photographer Gerrit VynEssays by Jared Diamond, John W. Fitzpatrick, Lyanda Lynn Haupt, and Scott Weidensaul 
The Living Bird
explores the relationship between birds and people through over 250 images by wildlife photographer Gerrit Vyn and thought-provoking essays by some of the world's leading naturalists and bird enthusiasts. The book also marks the 100th anniversary of the Cornell Lab of Ornithology, a world leader in the study, appreciation, and conservation of... View Details


Bird Bingo
by Christine Berrie (Illustrator)

This beautifully illustrated bingo game features 64 species of birds from around the world. Spot all kinds of birds—from the robin to the puffin and the kookaburra to the splendid fairywren—mark them off on your card and bingo! Contains 64 superbly illustrated bird tokens, one board, 12 bingo cards, and brightly colored counters for you to mark up your card, as well as a leaflet containing basic information and a few quirky traits for all of the birds featured. View Details


Bird & Snail (The Adventures of Bird & Snail) (Volume 1)
by Mr. Ryan Jerome Ramos (Author), Mr. Ryan Jerome Ramos (Creator), Mr. Ryan Jerome Ramos (Creator), Mrs. Heidi Leigh Ramos (Creator)

Bird and Snail is a charming story about curiosity, unexpected opportunities, and having the courage to explore the world with a new friend. View Details


I Know Why the Caged Bird Sings
by Maya Angelou (Author), Oprah Winfrey (Foreword)

Here is a book as joyous and painful, as mysterious and memorable, as childhood itself. I Know Why the Caged Bird Sings captures the longing of lonely children, the brute insult of bigotry, and the wonder of words that can make the world right. Maya Angelou’s debut memoir is a modern American classic beloved worldwide.
 
Sent by their mother to live with their devout, self-sufficient grandmother in a small Southern town, Maya and her brother, Bailey, endure the ache of abandonment and the prejudice of the local “powhitetrash.” At eight years old and back at her... View Details

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

The Big Five
What are the five biggest global challenges we face right now — and what can we do about them? This hour, TED speakers explore some radical solutions to these enduring problems. Guests include geoengineer Tim Kruger, president of the International Rescue Committee David Miliband, political scientist Ian Bremmer, global data analyst Sarah Menker, and historian Rutger Bregman.
Now Playing: Science for the People

#456 Inside a Conservation NGO
This week we take a close look at conservation NGOS: what they do, how they work, and - most importantly - why we need them. We'll be speaking with Shyla Raghav, the Climate Change Lead at Conservation International, about using strategy and policy to tackle climate change. Then we'll speak with Rebecca Shaw, Lead Scientist at the World Wildlife Fund, about how and why you should get involved with conservation initiatives.