Vocal Communication Flashcards
Which species claps their mandibles together to produce noise ?
Frigatebirds
Why do woodpeckers drum on hollow branches ?
To capture invertebrates
To communicate
Describe how the Palm Cockatoo generates noise.
Tool use
Uses a stick to drum on hollow logs.
Which system produces vocal communication ?
The respiratory system
What is the role of the larynx in birds ?
Prevents food entering the respiratory tract
no sound production
List the birds that do not have a Syrinx
Ratites, Storks, New world vulture
What noises can birds without syrinx’s make ?
Only Grunts and hisses.
Where is the syrinx located ?
Where the trachea branches into 2 bronchi.
Describe the structure of the Syrinx
Clavicular air sac
Than Syringeal muscles
Trachea
Within each is the internal tympaniform membrane opposite erectile tissue.
How is noise produced in a bird ?
It forces air along the bronchial tube, past the Tympanal membrane
Diameter and protrusion can be adjusted.
As air passes the tympanum vibrates and sound is created.
How can sound produced in the syrinx be modified by the bird ?
Opening & closing beak
& changing its shape.
What is special about the syrinx ?
Very efficient organ
Can use 2 bronchi separately.
Which species can sing with one side of the bronchus whilst breathing through the other ?
Canaries
Which species can double the rate at which they sing using alternation ?
Cowbirds.
sing rapid notes alternating form either side of the bronchus.
Describe the bronchi use of thrushes.
Sing rising notes from one side of the bronchus
Sing falling notes from the other.
Which group of birds are Songs limited to ?
Passeriformes (perching birds)
What are songs important for ?
Reproduction
Usually complex
Which vocalisations are under the influence of sex hormones ?
Songs
Why do birds sing in a dawn chorus ?
Air is still- good sound transmission
Fewer predators
Insects less easy to find (no conflict between foraging & song)
Lay eggs in morning- (^ paternity success for males)
What are calls ?
Acoustically simple
Means of announcing food or predation
Not sexual (not male bias)
Describe how offspring communicate temperature requirements to pelican parents
Air space in egg enables communication
Occurs late in embryonic development
Communicate whether too hot or too cold
Parents can regulate incubation.
What are the benefits to synchronised hatching in quails ?
Group benefits- diluted predation threat
Precocial, if late hatching may be isolated as parent foraging with siblings.
What does Precocial mean ?
Offspring are relatively mature upon hatching
Able to forage for food themselves.
How do quails synchronise hatching ?
Call to one another from within their eggs.
