Question | Answer |
example of altricial young | tree swallow |
example of precocial young | snowy plover |
eyes open, covered with feathers or down, leave nest after one or two days. | precocial |
eyes closed, little or no down, unable to leave nest, fed by parents: passerines | altricial |
covered with down, unable to leave nest, fed by parents | semialtricial |
eyes open, covered with down, able to walk but remain at nest are fed by parents: gulls, terns | semiprecocial |
Greater amount of yolk in eggs, yolk remaining at hatching, size of eyes and brain, and development of muscles | precocial |
greater size of gut and rate of growth after hatching | altricial |
characteristics of siblicidal birds: | competition for food
food provisioned in small packets
weaponry
competitive disparities
spatial confinement |
occurs when there is potential for uneven consumption of parental resources. | sibling competition |
killing a brother or a sister may be a common adaptive strategy among nestling birds, benefiting both the surviving offspring and the parents. | avian sublicide |
In Spring the birds orient toward the | North |
In Autumn the birds orient toward the | South |
migratory restlessness | zugunruhe |
Migrating birds orient by | postion of Sun
polarized light
Earth's magnetic field
infrasound |
How songs influence male bird. | identifies their species, sex, and occupancy of a territory. |
usually the longest and most complex vocalization produced by a bird | song |
short, simple, stereotyped bird songs | territorial songs |
long, complex, variable bird songs | sexual songs |
birds are unique among sauropsids in having | one-way flow of air through the lungs |
avian air sac system: | infraorbital sinus
clavicular air sac
axillary diverticulum into humerus
sternal diverticulum
cervical air sac
cranial thoracic air sac
caudal thoracic air sac
abdominal air sac
lung(only left side is shown) |
leads to abdominal air sac | mesobronchus |
dorsobronchus and ventrobronchus are connected by this within lungs | parabronchus |
Air route is from bronchus to mesobronchus to abdominal air sac to | dorsobronchus through parabronchi to ventrobronchus |
breath of air stays in system for two complete cycles. new breath occurs with each inspiration. results in continuous one-way flow of air through the lungs | two-cycle ventilation in birds |
into lungs during ( ) out of lungs during ( ) | expiration
inspiration |
occurs in each air capillary because gases in air capillary continuously encounter new supply of deoxygenated blood | countercurrent |
occurs because there is less oxygen in the distal air capillaries | cross current |
produced by ventral movement of sternum by contraction of intercostal muscles, and pulling up of ilium by contraction of longissimus dorsi | inspiration |
produced by relaxation of intercostal muscles, contraction of suprapubic and infrapubic abdominal muscles which pull the pelvis and tail downward | expiration |
furcula and coracoid spread and restore during | wingbeat |
sternum moves up and down during | wingbeat |
furcula spreads to inflate clavicular air sac, sternum elevates to compress posterior air sacs (anterior air sacs expanded, posterior collapsed) | wing depressed |
furcula collapses medially and sternum descends (posterior air sacs expanded, anterior collapsed) | upstroke |
Anatomic dead air space is that in which air is only pumped back and forth, about 30% in humans. Birds have about this amount | much less |