AUTHOR=Colombo Michael , Scarf Damian 

TITLE=Are There Differences in “Intelligence” Between Nonhuman Species? The Role of Contextual Variables

JOURNAL=Frontiers in Psychology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2020.02072

DOI=10.3389/fpsyg.2020.02072

ISSN=1664-1078

ABSTRACT=<p>We review evidence for <xref ref-type="bibr" rid="ref56">Macphail’s (1982</xref>, <xref ref-type="bibr" rid="ref57">1985</xref>, <xref ref-type="bibr" rid="ref58">1987)</xref><italic>Null Hypothesis</italic>, that nonhumans animals do not differ either qualitatively or quantitatively in their cognitive capacities. Our review supports the <italic>Null Hypothesis</italic> in so much as there are no qualitative differences among nonhuman vertebrate animals, and any observed differences along the qualitative dimension can be attributed to failures to account for contextual variables. We argue species do differ quantitatively, however, and that the main difference in “intelligence” among animals lies in the degree to which one must account for contextual variables.</p>