Editing Australian zebra finch (section)

==Song and other vocalisations==
Australian zebra finches are loud and boisterous singers. Their calls can be a loud ''beep'', ''meep'', ''oi!'' or ''a-ha!''. Their song is a few small beeps, leading up to a rhythmic song of varying complexity in males. Each male's song is different, although birds of the same bloodline will exhibit similarities, and all finches will overlay their own uniqueness onto a common rhythmic framework. Due to their extremely fine temporal-auditory discrimination, the zebra finch is able to recognise and respond to  micro-auditory details nested within their calls which human ears cannot detect.<ref>{{cite journal | pmc=5884127 | date=2016 | last1=Dooling | first1=R. J. | last2=Prior | first2=N. H. | title=Do we hear what birds hear in birdsong? | journal=Animal Behaviour | volume=124 | pages=283–289 | doi=10.1016/j.anbehav.2016.10.012 | pmid=29628517 }}</ref>

Sons generally learn the song of their fathers with little variation. There is a critical sensitive period during which juvenile males learn their songs by imitating a mature, male tutor.<ref name=":0">{{Cite journal|last1=Brainard|first1=Michael S.|last2=Doupe|first2=Allison J.|date=16 May 2002|title=What songbirds teach us about learning|journal=Nature|language=en|volume=417|issue=6886|pages=351–358|doi=10.1038/417351a|issn=0028-0836|pmid=12015616|bibcode=2002Natur.417..351B |s2cid=4329603}}</ref> Subsong (early, poorly structured vocalisations) evolve into 'plastic song'. This plastic song is variable between renditions but begins to incorporate some recognisable elements of tutor songs.<ref name=":0" /> A study conducted by Nottebohm et al., has shown that birds were able to successfully imitate their tutor's song after relatively short exposure (40 playbacks of the motifs lasting 30 seconds total) over the duration of their sensitive learning period.<ref>{{Cite journal|last1=Tchernichovski|first1=Ofer|last2=Lints|first2=Thierry|last3=Mitra|first3=Partha P.|last4=Nottebohm|first4=Fernando|date=26 October 1999|title=Vocal imitation in zebra finches is inversely related to model abundance|journal=Proceedings of the National Academy of Sciences of the United States of America|volume=96|issue=22|pages=12901–12904|issn=0027-8424| pmc=23154 |pmid=10536020|doi=10.1073/pnas.96.22.12901|bibcode=1999PNAS...9612901T |doi-access=free}}</ref> These birds eventually form a "template" of what their correct song should sound like. They rely on auditory feedback for both song learning and practice as juveniles and song maintenance as adults. Adult birds maintain their songs by correcting any deviations from their target song template. During adulthood, by around 90 days, the bird's song goes through a crystallisation phase where their song template is stable and it no longer changes.<ref name=":0" /> The learning process can be delayed by exposure to [[Noise pollution|traffic noise]].<ref name="Brumm 2021">{{cite journal |last1=Brumm |first1=Henrik |last2=Goymann |first2=Wolfgang |last3=Derégnaucourt |first3=Sébastien |last4=Geberzahn |first4=Nicole |last5=Zollinger |first5=Sue Anne |title=Traffic noise disrupts vocal development and suppresses immune function |journal=Science Advances |date=2021 |volume=7 |issue=20 |pages=eabe2405 |doi=10.1126/sciadv.abe2405|pmid=33980481 |pmc=8115921 |bibcode=2021SciA....7.2405B |doi-access=free }}</ref>

Male Australian zebra finches begin to sing at puberty, while females lack a singing ability.<ref name= awd/> This is due to a developmental difference, where in the embryo, the male zebra finch produces testosterone, which is transformed into estradiol in the brain, which in turn leads to the development of the nervous system for a song system.<ref>{{cite journal|last1=Gahr|first1=M|last2=Konishi|first2=M.|year=1988|title=Developmental changes in estrogen-sensitive neurons in the forebrain of the zebra finch|journal=Proceedings of the National Academy of Sciences|volume=85|issue=19|pages=7380–7383|doi=10.1073/pnas.85.19.7380 |pmid=3174641|pmc=282190|bibcode=1988PNAS...85.7380G|url=http://authors.library.caltech.edu/1609/1/GAHpnas88.pdf|doi-access=free}}</ref> There are multiple areas of the brain involved in the production of song. When a bird is singing a learned song, the [[HVC (avian brain region)|HVC]] projects to the robust nucleus of the [[archistriatum]] (RA), which itself projects to the [[hypoglossal nerve|hypoglossal motoneuron]]s. These motoneurons control the muscles of the trachea and syrinx. When learning a new song, the HVC sends efferents to Area X in the lobus parolfactorius, which connects to the medial nucleus of the dorsolateral thalamus (DLM). This structure connects to the lateral magnocellular nucleus of the anterior neostriatum (LMAN), which projects to the RA, and continues like a normal learned song would. The function of the various areas involved in learning is still being investigated.<ref name="ScharffNottebohm1991">{{cite journal|last1=Scharff|first1=C|last2=Nottebohm|first2=F|title=A comparative study of the behavioral deficits following lesions of various parts of the zebra finch song system: implications for vocal learning|journal=The Journal of Neuroscience|volume=11|issue=9|year=1991|pages=2896–2913|issn=0270-6474|doi=10.1523/JNEUROSCI.11-09-02896.1991|pmid=1880555|pmc=6575264|doi-access=free}}</ref> Area X is likely involved in the acquisition of a new song,<ref name="SohrabjiNordeen1990">{{cite journal|last1=Sohrabji|first1=Farida|last2=Nordeen|first2=Ernest J.|last3=Nordeen|first3=Kathy W.|title=Selective impairment of song learning following lesions of a forebrain nucleus in the juvenile zebra finch|journal=Behavioral and Neural Biology|volume=53|issue=1|year=1990|pages=51–63|issn=0163-1047|doi=10.1016/0163-1047(90)90797-A|pmid=2302141}}</ref> whereas the LMAN likely serves a key role in the [[neuroplasticity|plasticity]] necessary for learning.<ref name="ScharffNottebohm1991"/> Activation of song behaviour later depends on androgens.<ref>{{cite journal|last1=Gurney|first1=ME|last2=Konishi|first2=M.|year=1980|title=Hormone-induced sexual differentiation of brain and behavior in zebra finches|journal=Science|volume=208|issue=4450|pages=1380–1383|doi=10.1126/science.208.4450.1380|pmid=17775725|bibcode=1980Sci...208.1380G |s2cid=11669349}}</ref>

Because Australian zebra finch males learn their songs from their surroundings, they are often used as avian [[model organisms]] to investigate the neural bases of learning, memory, and sensorimotor integration. For example, studies have investigated the role of FoxP2 in song learning and have found that in young finches both knockdown and overexpression of FoxP2 in the striatal song control nucleus, Area X, prevents accurate song learning and tutor imitation.<ref>{{Cite journal|last1=Haesler|first1=Sebastian|last2=Rochefort|first2=Christelle|last3=Georgi|first3=Benjamin|last4=Licznerski|first4=Pawel|last5=Osten|first5=Pavel|last6=Scharff|first6=Constance|date=4 December 2007|title=Incomplete and Inaccurate Vocal Imitation after Knockdown of FoxP2 in Songbird Basal Ganglia Nucleus Area X|journal=PLOS Biology|volume=5|issue=12|pages=e321|doi=10.1371/journal.pbio.0050321|issn=1545-7885| pmc=2100148 |pmid=18052609 |doi-access=free }}</ref><ref>{{Cite journal|last1=Heston|first1=Jonathan B.|last2=White|first2=Stephanie A.|date=18 February 2015|title=Behavior-linked FoxP2 regulation enables zebra finch vocal learning|journal= 	The Journal of Neuroscience|volume=35|issue=7|pages=2885–2894|doi=10.1523/JNEUROSCI.3715-14.2015|issn=1529-2401| pmc=4331621 |pmid=25698728}}</ref> These studies also have implications for human speech. Individuals heterozygous for a point mutation in FOXP2 manifest a speech disorder.<ref>{{Cite journal|last1=Lai|first1=Cecilia S. L.|last2=Fisher|first2=Simon E.|last3=Hurst|first3=Jane A.|last4=Vargha-Khadem|first4=Faraneh|last5=Monaco|first5=Anthony P.|date=4 October 2001|title=A forkhead-domain gene is mutated in a severe speech and language disorder|journal=Nature|language=en|volume=413|issue=6855|pages=519–523|doi=10.1038/35097076|issn=0028-0836|pmid=11586359|bibcode=2001Natur.413..519L |hdl=11858/00-001M-0000-0012-CB9C-F |s2cid=4421562|hdl-access=free}}</ref> Because of similar expression patterns between humans and songbirds, the Australian zebra finch is used as a model to study FoxP2 expression and function.<ref>{{Cite journal|last1=Teramitsu|first1=Ikuko|last2=Kudo|first2=Lili C.|last3=London|first3=Sarah E.|last4=Geschwind|first4=Daniel H.|last5=White|first5=Stephanie A.|date=31 March 2004|title=Parallel FoxP1 and FoxP2 Expression in Songbird and Human Brain Predicts Functional Interaction|journal=Journal of Neuroscience|language=en|volume=24|issue=13|pages=3152–3163|doi=10.1523/JNEUROSCI.5589-03.2004|issn=0270-6474|pmid=15056695|pmc=6730014}}</ref> The zebra finch genome was the second bird genome to be sequenced, in 2008, after that of the [[chicken]].<ref>[https://web.archive.org/web/20060828021715/http://genome.wustl.edu/genome.cgi?GENOME=Taeniopygia%20guttata&SECTION=research ''Taeniopygia guttata'' Research Status]. Washington University in St. Louis</ref>

The Australian zebra finch uses an acoustic signal to communicate to embryos. It gives an incubation call to its eggs when the weather is hot—above {{convert|26|C|F}}—and when the end of their incubation period is near. This call alters the growth and behaviour of the chicks, with chicks that were given an incubation call having less mass at the end of the nestling phase when they experienced higher nest temperatures. This contrasts with chicks that were not given an incubation call, which have a higher mass at the end of nestling after being exposed to high nest temperatures. Additionally, the chicks called to as an embryo are more likely to call after experiencing high nest temperatures.<ref>{{cite journal|last1=Mariette|first1=Mylene M.|last2=Buchanan|first2=Katherine L.|year=2016|title=Prenatal acoustic communication programs offspring for high posthatching temperatures in a songbird.|journal=Science|volume=353|issue=6301|pages=812–814|doi=10.1126/science.aaf7049|pmid=27540172|bibcode=2016Sci...353..812M |doi-access=free}}</ref>

Calling behaviour is used by Australian zebra finches to negotiate parental care duties. In an experiment that delayed the return of the males to the nest, it was found that the resulting duets were shorter and calls were made more often.<ref>{{cite journal |last1=Boucaud |first1=Ingrid CA |last2=Mariette |first2=Mylene M. |last3=Villain |first3=Avelyne S.|last4=Vignal |first4=Clémentine|date=February 2016 |title=Vocal negotiation over parental care? Acoustic communication at the nest predicts partners' incubation share. |journal=[[Biological Journal of the Linnean Society]] |volume=117 |issue=2 |pages=322–336 |doi=10.1111/bij.12705 |doi-access=free |hdl=10536/DRO/DU:30082281 |hdl-access=free }}</ref> This is the first species that vocal negotiation over parental care has ever been reported.<ref>{{cite news |last=Izaac |first=Joshua |date=2 December 2015 |title= Zebra finches negotiate parental duties through song|url=http://www.australiangeographic.com.au/news/2015/12/zebra-finch-duets |work=[[Australian Geographic]] |access-date= 5 October 2017 }}</ref>