Getting to the Bottom of Face Processing. Species-Specific Inversion Effects for Faces and Behinds in Humans and Chimpanzees (Pan Troglodytes)
For social species such as primates, the recognition of conspecifics is crucial for their survival. As demonstrated by the ‘face inversion effect’, humans are experts in recognizing faces and unlike objects, recognize their identity by processing it configurally. The human face, with its distinct fe...
| Main Authors: | , |
|---|---|
| Format: | Online |
| Language: | English |
| Published: |
Public Library of Science
2016
|
| Online Access: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5130172/ |
| id |
pubmed-5130172 |
|---|---|
| recordtype |
oai_dc |
| spelling |
pubmed-51301722016-12-15 Getting to the Bottom of Face Processing. Species-Specific Inversion Effects for Faces and Behinds in Humans and Chimpanzees (Pan Troglodytes) Kret, Mariska E. Tomonaga, Masaki Research Article For social species such as primates, the recognition of conspecifics is crucial for their survival. As demonstrated by the ‘face inversion effect’, humans are experts in recognizing faces and unlike objects, recognize their identity by processing it configurally. The human face, with its distinct features such as eye-whites, eyebrows, red lips and cheeks signals emotions, intentions, health and sexual attraction and, as we will show here, shares important features with the primate behind. Chimpanzee females show a swelling and reddening of the anogenital region around the time of ovulation. This provides an important socio-sexual signal for group members, who can identify individuals by their behinds. We hypothesized that chimpanzees process behinds configurally in a way humans process faces. In four different delayed matching-to-sample tasks with upright and inverted body parts, we show that humans demonstrate a face, but not a behind inversion effect and that chimpanzees show a behind, but no clear face inversion effect. The findings suggest an evolutionary shift in socio-sexual signalling function from behinds to faces, two hairless, symmetrical and attractive body parts, which might have attuned the human brain to process faces, and the human face to become more behind-like. Public Library of Science 2016-11-30 /pmc/articles/PMC5130172/ /pubmed/27902685 http://dx.doi.org/10.1371/journal.pone.0165357 Text en © 2016 Kret, Tomonaga http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
| repository_type |
Open Access Journal |
| institution_category |
Foreign Institution |
| institution |
US National Center for Biotechnology Information |
| building |
NCBI PubMed |
| collection |
Online Access |
| language |
English |
| format |
Online |
| author |
Kret, Mariska E. Tomonaga, Masaki |
| spellingShingle |
Kret, Mariska E. Tomonaga, Masaki Getting to the Bottom of Face Processing. Species-Specific Inversion Effects for Faces and Behinds in Humans and Chimpanzees (Pan Troglodytes) |
| author_facet |
Kret, Mariska E. Tomonaga, Masaki |
| author_sort |
Kret, Mariska E. |
| title |
Getting to the Bottom of Face Processing. Species-Specific Inversion Effects for Faces and Behinds in Humans and Chimpanzees (Pan Troglodytes) |
| title_short |
Getting to the Bottom of Face Processing. Species-Specific Inversion Effects for Faces and Behinds in Humans and Chimpanzees (Pan Troglodytes) |
| title_full |
Getting to the Bottom of Face Processing. Species-Specific Inversion Effects for Faces and Behinds in Humans and Chimpanzees (Pan Troglodytes) |
| title_fullStr |
Getting to the Bottom of Face Processing. Species-Specific Inversion Effects for Faces and Behinds in Humans and Chimpanzees (Pan Troglodytes) |
| title_full_unstemmed |
Getting to the Bottom of Face Processing. Species-Specific Inversion Effects for Faces and Behinds in Humans and Chimpanzees (Pan Troglodytes) |
| title_sort |
getting to the bottom of face processing. species-specific inversion effects for faces and behinds in humans and chimpanzees (pan troglodytes) |
| description |
For social species such as primates, the recognition of conspecifics is crucial for their survival. As demonstrated by the ‘face inversion effect’, humans are experts in recognizing faces and unlike objects, recognize their identity by processing it configurally. The human face, with its distinct features such as eye-whites, eyebrows, red lips and cheeks signals emotions, intentions, health and sexual attraction and, as we will show here, shares important features with the primate behind. Chimpanzee females show a swelling and reddening of the anogenital region around the time of ovulation. This provides an important socio-sexual signal for group members, who can identify individuals by their behinds. We hypothesized that chimpanzees process behinds configurally in a way humans process faces. In four different delayed matching-to-sample tasks with upright and inverted body parts, we show that humans demonstrate a face, but not a behind inversion effect and that chimpanzees show a behind, but no clear face inversion effect. The findings suggest an evolutionary shift in socio-sexual signalling function from behinds to faces, two hairless, symmetrical and attractive body parts, which might have attuned the human brain to process faces, and the human face to become more behind-like. |
| publisher |
Public Library of Science |
| publishDate |
2016 |
| url |
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5130172/ |
| _version_ |
1613748413752410112 |