News Main Animals Archaeology Dinosaurs Earth History Human Animal Space Tech   Herman Berkhoudt/Philip Greenspun |   Noisy Setting An image of a great tit is shown against an image of London's urban landscape. New research shows birds often increase the pitch and sound level of their calls to compete with traffic noise.   « back to article

advertisement Related News Feeds Discovery News Widget Download the widget to your site, then choose your favorite news feeds. It's easy!   Discovery News Video Our reporters get out and about with scientists in the field ... and the occasional animal or two.   RSS Feeds Get all Discovery News top stories in text or video. Or choose from eight subject areas.   Discovery News Podcasts Stay on top of the latest Discovery News in text and video, including Friday News Feedbag and top breakthroughs.   Put Discovery News on Your Site!

our sites

• Animal Planet
• Curiosity
• Discovery Channel
• Discovery Kids
• Discovery Fit & Health
• HD Theater
• Investigation Discovery
• Military Channel
• Oprah Winfrey Network
• Planet Green
• Science Channel
• TLC
• Turbo
• Velocity

• Consumer Guide Auto
• Consumer Guide Products
• Discovery Education
• Discovery News
• Discovery Retreats
• HowStuffWorks
• MyDiscovery
• Petfinder
• Student Competitions
• TreeHugger

video

• Discovery Channel Video

 

mobile

• Mobile Applications
• Wallpaper & Ringtones
• Mobile Video
• Mobile Web
• Text Alerts

shop

• Discovery Store
• DVDs & Books
• Custom Gear
• Toys & Games
• Gift Sets
• Sale
• Discovery Adventures
• Student Adventures
• Discovery TS
• Discovery Corporate Sales

stay connected

• Email Newsletters
• RSS
• Twitter
• Facebook

corporate

• Discovery Communications, LLC
• Viewer Relations
• Advertising
• Careers @ Discovery
• Privacy Policy
• Visitor Agreement

Image Credits Herman Berkhoudt/Philip Greenspun |

Copyright © 2012 Discovery Communications, LLC. The number-one nonfiction media company.