Anatomical Specializations for Nocturnality in a Critically Endangered Parrot, the Kakapo (Strigops habroptilus)
2011

Visual System of the Kakapo Parrot

publication Evidence: moderate

Author Information

Author(s): Jeremy R. Corfield, Anna C. Gsell, Dianne Brunton, Christopher P. Heesy, Margaret I. Hall, Monica L. Acosta, Andrews N. Iwaniuk

Primary Institution: Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada

Hypothesis

How has the Kakapo's visual system adapted to its nocturnal lifestyle?

Conclusion

The Kakapo has a unique visual system that combines traits of both nocturnal and diurnal birds, suggesting enhanced light sensitivity but poor visual acuity.

Supporting Evidence

  • The Kakapo's orbits are significantly more convergent than other parrots, indicating a larger binocular field.
  • The Kakapo exhibits an eye shape consistent with nocturnal birds, suggesting adaptations for low light.
  • The optic nerve and tectofugal visual pathway are significantly smaller in the Kakapo compared to other parrots.
  • The retinal morphology of the Kakapo is similar to both diurnal and nocturnal birds, indicating a specialized adaptation.

Takeaway

The Kakapo, a nocturnal parrot, has special eyes that help it see better in the dark, but it doesn't see as clearly as other birds.

Methodology

The study involved a detailed morphological analysis of the Kakapo's orbits, brain, eye, and retina, comparing them with other birds.

Limitations

The study is limited by the small sample size and the challenges of studying a critically endangered species.

Digital Object Identifier (DOI)

10.1371/journal.pone.0022945

Want to read the original?

Access the complete publication on the publisher's website

View Original Publication