Birds have primate-like numbers of neurons in the forebrain

2016/06/13 by Seweryn Olkowicz, Martin Kocourek, Radek Lučan +4 · 1 voice · 41 citations
Biochemistry, Genetics and Molecular Biology · Psychology · Agricultural and Biological Sciences · #Animal Vocal Communication and Behavior #Primate Behavior and Ecology #Animal Behavior and Reproduction

paper · pdf · doi:10.1073/pnas.1517131113

Abstract

Some birds achieve primate-like levels of cognition, even though their brains tend to be much smaller in absolute size. This poses a fundamental problem in comparative and computational neuroscience, because small brains are expected to have a lower information-processing capacity. Using the isotropic fractionator to determine numbers of neurons in specific brain regions, here we show that the brains of parrots and songbirds contain on average twice as many neurons as primate brains of the same mass, indicating that avian brains have higher neuron packing densities than mammalian brains. Additionally, corvids and parrots have much higher proportions of brain neurons located in the pallial telencephalon compared with primates or other mammals and birds. Thus, large-brained parrots and corvids have forebrain neuron counts equal to or greater than primates with much larger brains. We suggest that the large numbers of neurons concentrated in high densities in the telencephalon substantially contribute to the neural basis of avian intelligence.

Cited by

• Traffic noise inhibits cognitive performance in a songbird
• Who’s a clever bird — now? A brief history of parrot cognition
• Birds of a feather? Parrot and corvid cognition compared
• Effects of timed food availability on reproduction and metabolism in zebra finches: Molecular insights into homeostatic adaptation to food-restriction in diurnal vertebrates
• Music at the Threshold from the Sacred to the Dangerous
• Innovative flavoring behavior in Goffin’s cockatoos
• How smart was T. rex ? Testing claims of exceptional cognition in dinosaurs and the application of neuron count estimates in palaeontological research
• Avian cranial evolution is influenced by shape interactions between hard and soft tissue traits
• What we (don’t) know about parrot welfare: Finding welfare indicators through a systematic literature review
• Larger Fish Have Larger Brains With More Neurons Across but Not Within Cohorts Raised in Different Growth Conditions
• Science, sensitivity and the sociozoological scale: Constituting and complicating the human-animal boundary at the 1875 Royal Commission on Vivisection and beyond
• From fossils to mind
• Genomic and neurobiological bases of variation in fighting strategies in gamecocks
• The evolution of brain neuron numbers in amniotes
• Comparative brain structure and visual processing in octopus from different habitats
• Coevolution of relative brain size and life expectancy in parrots
• Proactive prosociality in a cooperatively breeding corvid, the azure-winged magpie (Cyanopica cyana). [europepmc]
• Fish perform like mammals and birds in inhibitory motor control tasks. [europepmc]
• The detour paradigm in animal cognition. [europepmc]
• Evolution of cognitive and neural solutions enabling numerosity judgements: lessons from primates and corvids. [europepmc]
• Physiology of Astroglia. [europepmc]
• Neocortical Association Cell Types in the Forebrain of Birds and Alligators. [europepmc]
• Sociality does not drive the evolution of large brains in eusocial African mole-rats. [europepmc]
• Parrots have evolved a primate-like telencephalic-midbrain-cerebellar circuit. [europepmc]
• Homology, neocortex, and the evolution of developmental mechanisms. [europepmc]
• Parrot Genomes and the Evolution of Heightened Longevity and Cognition. [europepmc]
• An Evolutionary Perspective on Why Food Overconsumption Impairs Cognition. [europepmc]
• Transitive inference in Polistes paper wasps. [europepmc]
• White matter volume and white/gray matter ratio in mammalian species as a consequence of the universal scaling of cortical folding. [europepmc]
• Evolution of the Chordate Telencephalon. [europepmc]
• Artificial selection on brain size leads to matching changes in overall number of neurons. [europepmc]
• Transplantation of Human Brain Organoids: Revisiting the Science and Ethics of Brain Chimeras. [europepmc]
• ZEBrA: Zebra finch Expression Brain Atlas-A resource for comparative molecular neuroanatomy and brain evolution studies. [europepmc]
• 64-Channel Carbon Fiber Electrode Arrays for Chronic Electrophysiology. [europepmc]
• Whole-Brain Profiling of Cells and Circuits in Mammals by Tissue Clearing and Light-Sheet Microscopy. [europepmc]
• Extended parenting and the evolution of cognition. [europepmc]
• Variations of telencephalic development that paved the way for neocortical evolution. [europepmc]
• The emergence of the brain non-CpG methylation system in vertebrates. [europepmc]
• Retrotransposons as Drivers of Mammalian Brain Evolution. [europepmc]
• Genetically identified neurons in avian auditory pallium mirror core principles of their mammalian counterparts. [europepmc]
• The evolution of brain neuron numbers in amniotes. [europepmc]

Discussions

• Our intelligence and cognitive abilities are perhaps due to an expansion of our cerebral cortex. But surprisingly, compared to highly intelligent birds, primates have many more neurons in their cerebe [bsky, 41 points, 0 comments]

Related

• Brain modularity across the theropod–bird transition: testing the influence of flight on neuroanatomical variation
• The Independent Evolution of the Enlargement of the Principal Sensory Nucleus of the Trigeminal Nerve in Three Different Groups of Birds
• Birds of a feather? Parrot and corvid cognition compared
• Variation in avian brain shape: relationship with size and orbital shape
• The evolution of brain neuron numbers in amniotes