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Cited by 86Animal Vocal Communication and BehaviorNeuroscience and Music PerceptionNeurogenesis and neuroplasticity mechanisms

Core and shell song systems unique to the parrot brain

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Chakraborty, Mukta, Walløe, Solveig, Nedergaard, Signe, Fridel, Emma E., Dabelsteen, Torben, Pakkenberg, Bente, Bertelsen, Mads F., Dorrestein, Gerry M. +3 more·2015·PLOS ONE
DOI 10.1371/journal.pone.0118496PMC PMC4479475
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Abstract

The ability to imitate complex sounds is rare, and among birds has been found only in parrots, songbirds, and hummingbirds. Parrots exhibit the most advanced vocal mimicry among non-human animals. A few studies have noted differences in connectivity, brain position and shape in the vocal learning systems of parrots relative to songbirds and hummingbirds. However, only one parrot species, the budgerigar, has been examined and no differences in the presence of song system structures were found with other avian vocal learners. Motivated by questions of whether there are important differences in the vocal systems of parrots relative to other vocal learners, we used specialized constitutive gene expression, singing-driven gene expression, and neural connectivity tracing experiments to further characterize the song system of budgerigars and/or other parrots. We found that the parrot brain uniquely contains a song system within a song system. The parrot "core" song system is similar to the song systems of songbirds and hummingbirds, whereas the "shell" song system is unique to parrots. The core with only rudimentary shell regions were found in the New Zealand kea, representing one of the only living species at a basal divergence with all other parrots, implying that parrots evolved vocal learning systems at least 29 million years ago. Relative size differences in the core and shell regions occur among species, which we suggest could be related to species differences in vocal and cognitive abilities.

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  • Parrot pallial song nuclei underwent a further duplication event to evolve a unique additional circuit, the shell song system, which is particularly well developed in large-brained parrots.

    “Intriguingly, parrot pallial song nuclei underwent a further duplication event to evolve a unique additional circuit, the so-called shell song system, which seems to be particularly well developed in large-brained parrots (45).”

    From Birds have primate-like numbers of neurons in the forebrain (2016) · cites this paper as [45]

    The Introduction and Discussion describe a parrot-specific shell system that evolved after a core-like system, and the Results report larger shell regions in larger-brained species. However, the paper does not establish that the pallial song nuclei underwent a duplication event; it presents the system’s evolutionary sequence as a hypothesis. The Discussion also notes a larger-brained exception, the kea, whose shell specialization is not robust. The indexed passages provide section labels but no page numbers. (LLM, conf=0.86)

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  • The relatively enlarged subpallium in large parrots is likely associated with their greater learning skills, including vocal learning, and enhanced foot and beak dexterity.

    “Because subpallial structures play an important role in sensory and motor learning and execution of motor behavior (15, 44), we suggest that the relatively enlarged subpallium in large parrots is likely associated with their greater learning skills, including vocal learning, and enhanced foot and beak dexterity (5, 6, 13, 45).”

    From Birds have primate-like numbers of neurons in the forebrain (2016) · cites this paper as [45]

    The Results section on core and shell area ratios reports larger song-nucleus shell regions in larger-brained parrot species typically considered to have more advanced vocal and cognitive abilities. The paper does not establish that the subpallium as a whole is relatively enlarged in large parrots or link that enlargement to foot and beak dexterity. (LLM, conf=0.83)

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Authors
Chakraborty, M., Walløe, S., Nedergaard, S., Fridel, E. E., Dabelsteen, T., Pakkenberg, B., Bertelsen, M. F., Dorrestein, G. M., Brauth, S. E., Durand, S. E., & Jarvis, E. D.
Affiliations
  • Howard Hughes Medical Institute (US)
  • University of Copenhagen (DK)
  • Danish National Police (DK)
  • Duke Medical Center (US)
  • Bispebjerg Hospital (DK)
  • Copenhagen Zoo (DK)
  • University of Maryland, College Park (US)
  • LaGuardia Community College (US)
Corresponding author
  • Chakraborty, Mukta
  • Walløe, Solveig
  • Nedergaard, Signe
  • Fridel, Emma E.
  • Dabelsteen, Torben
  • Pakkenberg, Bente
  • Bertelsen, Mads F.
  • Dorrestein, Gerry M.
  • Brauth, Steven E.
  • Durand, Sarah E.
  • Jarvis, Erich D.
ORCID
Venue
PLOS ONE
Publisher
Public Library of Science (PLoS)
Published
2015-06-24
Volume
10
Issue
6
Pages
e0118496
ISSN
1932-6203 (ISSN-L)
DOI
10.1371/journal.pone.0118496
PMC
PMC4479475
OpenAlex
W1598996539
Cited by
86
References
89
Citations by year
2026: 8 · 2025: 9 · 2024: 8 · 2023: 6 · 2022: 6 · 2021: 15 · 2020: 9 · 2019: 4 · 2018: 6 · 2017: 3 · 2016: 9 · 2015: 2 · 2014: 1
FWCI
5.80
Type
journal article
Language
en
Open access
Licence
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Research at the University of Copenhagen (University of Copenhagen) (publishedVersion, cc-by)
  • CUNY Academic Works (City University of New York) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • DukeSpace (Duke University) (submittedVersion, cc-by-nc-nd)
  • Figshare (submittedVersion, cc-by)
Funders
  • Howard Hughes Medical Institute
  • Danmarks Frie Forskningsfond
  • National Institutes of Health
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Developmental Biology › Animal Vocal Communication and Behavior
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Neuroscience and Music Perception
  • Life Sciences › Neuroscience › Developmental Neuroscience › Neurogenesis and neuroplasticity mechanisms
Keywords
vocal learning, vocal mimicry, budgerigars, avian brain evolution
MeSH terms
Animals, Brain, Humans, Learning, Music, New Zealand, Parrots, Vocalization, Animal

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