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Does 'Relationship Intelligence' Make Big Brains in Birds?

DOI:10.2174/1874196700801010006
Authors:
Isabella B. R. Scheiber at University of Vienna
Isabella B. R. Scheiber
Brigitte Weiß at University of Leipzig
Brigitte Weiß
Katharina Hirschenhauser at Pädagogische Hochschule Oberösterreich
Katharina Hirschenhauser
Claudia A F Wascher at Anglia Ruskin University
Claudia A F Wascher
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Abstract

Lately, Emery et al. developed a bird-specific modification of the "social brain hypothesis", termed "relationship intelligence hypothesis". Although the idea may be valuable, we doubt that it is supported by sufficient evidence and critically discuss some of the arguments raised by the authors in favour of their new idea.
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... For example, certain affiliative tactile behaviours, such as feeding or grooming others, are often used as indicators of close bonds between individuals and are expressed similarly in altricial and precocial mammals [75], but are, in contrast to altricial birds, uncommon or absent in many precocial birds [76]. However, both altricial and precocial species express social bonds in a variety of other ways, including vocal and visual displays ( [76][77][78][79][80][81] for a mammalian review) and chemical [82] cues, increased tolerance and spatial proximity [83][84][85]. In particular, the spatial association between individuals is often used as a proxy for determining social relationships ( [86][87][88], but see [89]). ...
... In sum, both altricial and precocial birds and mammals resort to a large variety of displaying affiliative bonds. The lack of any one of these above indicators of social bonds, however, does not necessarily infer weak and/or low quality affiliative relationships between precocial or altricial mammals or birds, since other forms of expressing relationships may be in place [85]. ...
The importance of the altricial – precocial spectrum for social complexity in mammals and birds – a review
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... In addition, the nature of social relationships seems to highly impact upon brain size, irrespective of group stability and social dynamics. For instance, species forming long-term relationships and/or partnerships tend to have bigger brains than species engaging in short-term or seasonal relationships only ( 17 , but see 29 ). Hence, interacting with particular individuals over time-rather than interacting with many individuals and/or over limited periods only-seems to be a highly cognitively challenging enterprise 30 . ...
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Full-text available
  • Dec 2020
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Thesis
Full-text available
  • Jun 2016
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Higher Cognitive Abilities in Birds: A Comparative Evolutionary Analysis
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