Does hippocampal size correlate with the degree of caching specialization

摘要: A correlation between the degree of specialization for food hoarding and volume hippocampal formation in passerine birds has been accepted over a decade. The relationship was first demonstrated family-level comparisons, subsequently species comparisons within two families containing large number species, Corvidae Paridae. Recently, this approach criticized as invalid excessively adaptationist. recent test predicted trends with data pooled from previous studies found no evidence such either these families. This result interpreted support critique. Here we reanalyse original dataset also include additional new on several parid species. Our results show surprising difference continents, North American possessing significantly smaller hippocampi than Eurasian ones. Controlling continent effect makes capacity/hippocampal clearly significant both We discuss possible reasons effect.