Biology Reference
In-Depth Information
circannual events, and provide some ideas about how they could be coordi-
nated and controlled on a seasonal basis.
2. SEASONAL COURTSHIP AND TERRITORIAL BEHAVIOR
Seasonally reproducing animals often display courtship or territorial
behavior associated with their mating season. For instance, male songbirds
sing complex courtship songs robustly in their breeding season both to attract
mates and deter othermales. Consequently, singing is a circannual behavior in
various species, including canaries (
Serinus canaria
), song sparrows (
Melospiza
melodia
), and many others. Songbirds have a system of nuclei (clusters of neu-
rons in the central nervous system) that control song production and learning
(
Fig. 9.2
). The motor pathway controlling song production consists of pro-
jections from the interfacial nucleus of the nidopallium (Nif ) to the
nidopallial vocal nucleus HVC (used as a proper name). HVC projects to
the robust nucleus of the archipallium (RA), which then projects to the mid-
brain and brainstem syringeal and respiratory motoneuronal pools that acti-
vate the muscles used for vocalizing (
Brenowitz, Margoliash, & Nordeen,
HVC
Nif
lMAN
RA
Area X
DLM
Syringeal and
respiratory motor
neurons
Figure 9.2 Birdsong song control system. Projections of the motor pathway, which con-
trols song production, are shown by the solid lines. Projections of the anterior forebrain
pathway, which controls song learning and development, are shown by the dotted
lines. DLM, dorsal lateral nucleus; HVC, used as proper name; lMAN, lateral mag-
nocellular nucleus of the anterior nidopallium; Nif, interfacial nucleus of the nidopallium;
RA, robust nucleus of the arcopallium. Model
is based on
Nottebohm (2005)
and
Tramontin and Brenowitz (2000)
.
