The beak, bill or rostrum is an external anatomical structure of birds which, in addition to eating, is used for grooming, manipulating objects, killing prey, probing for food, courtship and feeding their young. The term also refers to a similar mouthpart in some cephalopods, cetaceans, pufferfishes, turtles, Anuran tadpoles and sirens.
Welcome to CWAnswers
CWAnswers is your guide to the sprawling world wide web. The directory aims to provide a useful guide made by users. You can share your knowledge as well - simply sign up and edit your first entry. For questions just contact the team at support - at - cwanswers.com.
Weblinks for Beak
Top 10 for Beak
Things about Beak you find nowhere else.
Select content modules
Beak's Blog
Beak's Blog. Random comments about technology and life in Mexico ... Beak's Blog is proudly powered by WordPress. Entries (RSS) and Comments (RSS) ...www.bekas.org/john/blog/Beak — Blogs, Pictures, and more on WordPress
... Oddest-looking bird, White Face, Comical Waddle, Enormous Beak, Colored Bands ... shape, Plant Lice, Insect & Pest, Sharp Beak, green plants, Harmful to plants " ...en.wordpress.com/tag/beak/Beak Brothers | Darren & Leighton | Travel Blog
We're 2 brothers (well not quite but we do look very similar! ... Blogs & Travel Journals. by Beak Brothers, order by Date newest first. " back 1 10 next " ...www.travelblog.org/Bloggers/Beak-Brothers/Beak's Blog " Blog Archive " Welcome to Beak's Blog
Beak's Blog. Random comments about technology and life in Mexico. Linux, I ... Beak's Blog is proudly powered by WordPress. Entries (RSS) and Comments (RSS) ...www.bekas.org/john/blog/2006/06/25/welcome/Beak's Handmade Blog
... home of Beak Knits * Main Site Search Patterns Blog. Where do roads ... Beak's Handmade Blog is proudly powered by WordPress. Entries (RSS) and Comments (RSS) ...www.handmademom.com/blog/The beak, bill or rostrum is an external anatomical structure of birds which, in addition to eating, is used for grooming, manipulating objects, killing prey, probing for food, courtship and feeding their young. The term also refers to a similar mouthpart in some cephalopods, cetaceans, pufferfishes, turtles, Anuran tadpoles and sirens.
Anatomy
The beak has two holes called nares (nostrils) which connect to the hollow inner beak and thence to the respiratory system. The nares are usually located directly above the beak. In some birds, they are located in a fleshy, often waxy structure at the base of the beak called the cere (from Latin cera). The cere often contains the nares, and is an indicator of the reproductive cycle of budgerigars.
Petrels and albatrosses have external horny sheaths called naricorns that protect the nares. These are separately placed on either side of the base of the upper mandible in albatrosses, but fused, with an internal septum, on the top of the base of the upper mandible in petrels.. In the mallard, and perhaps in other ducks, there is no cere, and the nostrils are in the hard part of the beak, as a soft cere would be liable to injury when the duck dredges for food among submerged debris and stones.
On some birds, the tip of the beak is hard, dead tissue used for heavy-duty tasks such as cracking nuts or killing prey. On other birds, such as ducks, the tip of the bill is sensitive and contains nerves, for locating things by touch. The beak is worn down by use, so it grows continuously throughout the bird's life.
Uses of beaks
As noted by Darwin in his observations on Galapagos Finches, birds' beaks have evolved to suit the ecological niche they fill: Raptors have decurved (downward curving) beaks for ripping up meat. Hummingbirds have long thin beaks for reaching nectar. The spoonbill's beak allows it it to filter-feed in shallow water. Unlike jaws with teeth, beaks are not used for chewing. Birds swallow their food whole, and it is broken up in the gizzard.
Billing
During courtship, mated pairs of a variety of bird species touch and clasp each other's bills. This is called billing, and appears to strengthen the pair bond (Terres, 1980). Gannets raise their bills high and repeatedly clatter them (pictured); the male puffin nibbles at the female's beak; the male waxwing puts his bill in the female's mouth; and ravens hold each other's beaks in a prolonged "kiss".
See also
- Bird anatomy
References
- Gilbertson, Lance; Zoology Lab Manual; McGraw Hill Companies, New York; ISBN 0-07-237716-X (fourth edition, 1999)
- Terres, John. K. The Audubon Society Encyclopedia of North American Birds, New York: Alfred A. Knopf, 1980. ISBN 0-394-46651-9


























