List of animals by number of neurons

The following are two lists of animals ordered by the size of their nervous system. The first list shows number of neurons in their entire nervous system, indicating their overall neural complexity. The second list shows the number of neurons in the structure that has been found to be representative of animal intelligence.[1] The human brain contains 86 billion neurons, with 16 billion neurons in the cerebral cortex.[2][1]

Brief comparisons of number of whole brain neurons (top) and cerebral cortex neurons (bottom) among six mammals.

Overview

Neurons are the cells that transmit information in an animal's nervous system so that it can sense stimuli from its environment and behave accordingly. Not all animals have neurons; Trichoplax and sponges lack nerve cells altogether.

Neurons may be packed to form structures such as the brain of vertebrates or the neural ganglions of insects.

The number of neurons and their relative abundance in different parts of the brain is a determinant of neural function and, consequently, of behavior.

Whole nervous system

All numbers for neurons (except Caenorhabditis and Ciona), and all numbers for synapses (except Ciona) are estimations.

Name	Neurons in the brain & whole nervous system	Synapses	Details	Image	Source
Sponge	0				[3]
Trichoplax	0		Despite no nervous system, it exhibits coordinated feeding and response behaviors.[4]		[5]
Asplanchna brightwellii (rotifer)	about 200		Brain only		[6]
Tardigrade	about 200		Brain only		[7]
Ciona intestinalis larva (sea squirt)	231	8,617 (central nervous system only)			[8] [9]
Caenorhabditis elegans (roundworm)	302	~7,500	is the only organism to have its whole connectome (neuronal "wiring diagram") completed.[10][11][12]		[13]
Jellyfish	5,600		Hydra vulgaris (H. attenuate)		[14]
Megaphragma mymaripenne	7,400				[15]
Box jellyfish	8,700–17,500		adult Tripedalia cystophora (8 mm diameter) – does not include 1000 neurons in each of the four rhopalia		[16]
Medicinal leech	10,000				[17]
Pond snail	11,000				[18]
Sea slug	18,000				[19]
Amphioxus	20,000		central nervous system only		[20] [21]
Larval zebrafish	100,000				[22]
Lobster	100,000				[23]
Fruit fly	250,000	< 10,000,000	In 2020 a research group announced the most sophisticated connectome[24]		[25] [26]
Ant	250,000		Varies per species		[27]
Honey bee	960,000	~1×10^9			[28]
Cockroach	1,000,000				[29]
Anolis cristatellus	4,270,000				[30]
Guppy	4,300,000				[31]
Ocelot gecko	4,420,000				[32]
Anolis evermanni	4,920,000				[30]
Adult zebrafish	~10,000,000		cells (neurons + other)		[33]
Frog	16,000,000				[34]
Naked mole-rat	26,880,000				[35]
Little free-tailed bat	35,000,000				[36]
Smoky shrew	36,000,000				[37]
Short-tailed shrew	52,000,000				[37]
Common bent-wing bat	56,000,000				[36]
African sheath-tailed bat	59,000,000				[36]
Hottentot golden mole	65,000,000				[38]
Woermann's bat	66,000,000				[36]
Zenker's fruit bat	66,000,000				[36]
Commerson's roundleaf bat	67,000,000				[36]
Rufous trident bat	70,000,000				[36]
House mouse	71,000,000	~1×10^12			[39]
Nile crocodile	80,500,000				[40]
Heart-nosed bat	81,000,000				[36]
Golden hamster	90,000,000				[39]
Short-palated fruit bat	99,000,000				[36]
Ansell's mole-rat	103,000,000				[41]
Mashona mole-rat	113,000,000				[41]
Hairy-tailed mole	124,000,000				[38]
Eastern rock elephant shrew	129,000,000				[38]
Star-nosed mole	131,000,000				[37]
Zebra finch	131,000,000		Brain only		[42]
Silvery mole-rat	148,000,000				[41]
Four-toed elephant shrew	157,000,000				[38]
Eurasian blackcap	157,000,000				[42]
Wahlberg's epauletted fruit bat	162,000,000				[36]
Goldcrest	164,000,000				[42]
Cape mole-rat	170,000,000				[41]
Egyptian fruit bat	172,000,000				[36]
Mechow's mole-rat	174,000,000				[41]
Damaraland mole-rat	178,000,000				[41]
Franquet's epauletted fruit bat	186,000,000				[36]
Brown rat	200,000,000	~4.48×10^11			[43]
Guyenne spiny rat	202,000,000				[38]
Eastern mole	204,000,000				[37]
Red junglefowl	221,000,000				[42]
Great tit	226,000,000				[42]
Green-rumped parrotlet	227,000,000				[42]
Guinea pig	240,000,000				[39]
Gray mouse lemur	254,710,000				[44]
Common treeshrew	261,000,000				[45]
Hammer-headed bat	275,000,000				[36]
Pigeon	310,000,000		Brain only		[42]
Budgerigar	322,000,000				[42]
Cape dune mole-rat	361,000,000				[41]
Common blackbird	379,000,000				[42]
Ferret	404,000,000				[46]
Cockatiel	453,000,000				[42]
Gray squirrel	453,660,000				[35]
Banded mongoose	454,000,000				[46]
Prairie dog	473,940,000				[35]
Common starling	483,000,000				[42]
European rabbit	494,200,000				[35]
Octopus	500,000,000				[47]
Western tree hyrax	505,000,000				[38]
Common marmoset	636,000,000				[45]
Eastern rosella	642,000,000				[42]
Barn owl	690,000,000				[42]
Monk parakeet	697,000,000				[42]
Azure-winged magpie	741,000,000				[42]
Rock hyrax	756,000,000				[38]
Cat	760,000,000	~1×10^13			[48]
Black-rumped agouti	857,000,000				[39]
Magpie	897,000,000				[42]
Common hill myna	906,000,000				[42]
Northern greater galago	936,000,000				[45]
Western jackdaw	968,000,000				[42]
Eurasian jay	1.085×10^9				[42]
Alexandrine parakeet	1.096×10^9				[42]
Raccoon dog	1.16 × 10^9				[49]
Tanimbar corella	1.161×10^9				[42]
Emu	1.335×10^9				[42]
Three-striped night monkey	1.468×10^9				[45]
Rook	1.509×10^9				[42]
Grey parrot	1.566×10^9				[42]
Capybara	1.6×10^9				[39]
Jackal	1.73 ×10^9				[49]
Fox	2.11 × 10^9				[49]
Sulphur-crested cockatoo	2.122×10^9				[42]
Raccoon	2.148×10^9				[46]
Kea	2.149×10^9				[42]
Raven	2.171×10^9		Brain only		[42]
Domestic pig	2.22×10^9				[50]
Dog	2.253×10^9				[46]
Chihuahua (dog)	2.51 × 10^9				[49]
Dog (Chow Chow)	2.61 × 10^9				[49]
Dog (Yorkshire Terrier)	2.64 × 10^9				[49]
Springbok	2.72×10^9				[50]
Dog (West Highland White Terrier)	2.83 × 10^9				[49]
Blesbok	3.06×10^9				[50]
Blue-and-yellow macaw	3.136×10^9		Brain only		[42]
Common squirrel monkey	3.246×10^9				[45]
Crab-eating macaque	3.44×10^9				[44]
Dog (German Shepherd)	3.53 × 10^9				[49]
Tufted capuchin	3.691×10^9				[45]
Bonnet macaque	3.78×10^9				[44]
Striped hyena	3.885×10^9				[46]
Dog (Komondor)	3.99 × 10^9				[49]
Dog (Transylvanian Hound)	4.39 × 10^9				[49]
Lion	4.667×10^9				[46]
Greater kudu	4.91×10^9				[50]
Rhesus macaque	6.376×10^9				[45]
Brown bear	9.586×10^9				[46]
Giraffe	1.075×10^10				[50]
Yellow baboon	1.095×10^10				[44]
Chimpanzee	2.8×10^10				[51]
Orangutan	3.26×10^10				[52]
Gorilla	3.34×10^10				[52]
Human	8.6×10^10	~1.5×10^14	Neurons for average adult		[53][54][55]
African elephant	2.57×10^11				[56][57]

Sensory-associative structure

The cerebral cortex is a structure of particular interest at the intersection between comparative neuroanatomy and comparative cognitive psychology. Historically, it had been assumed that since only mammals have a cerebral cortex, only they benefit from the information processing functions associated with it, notably awareness and thought.[58] It is now known that non-avian reptiles also have a cerebral cortex and that birds have a functional equivalent called the dorsal ventricular ridge (DVR), which in fact appears to be a modification subsequent to the reptilian cortex. A modern understanding of comparative neuroanatomy now suggests that for all vertebrates, the pallium roughly corresponds to this general sensory-associative structure.[59] It is also a widely accepted view that arthropods and closely related worms have an equivalent structure, the corpora pedunculata, more commonly known as mushroom bodies. In fact this structure in invertebrates and the pallium in vertebrates may have a common evolutionary origin from a common ancestor.[60]

Given the apparent function of the sensory-associative structure, it has been suggested that the total number of neurons in the pallium or its equivalents may be the best predictor of intelligence when comparing species, being more representative than total brain mass or volume, brain-to-body mass ratio, or encephalization quotient (EQ).[1] It may thus be reasonably assumed that the total number of neurons in an animal's corresponding sensory-associative structure strongly relates to its degree of awareness, breadth and variety of subjective experiences, and intelligence.[1]

Methods

The methods used to arrive at the numbers in this list include neuron count by isotropic fractionator, optical fractionator or estimation based on correlations observed between number of cortical neurons and brain mass within closely related taxa. Isotropic fractionation is often considered more straightforward and reliable than optical fractionation which may yield both overestimates and underestimates.[61] Estimation based on brain mass and taxon is to be considered the least reliable method.

Common name	Average number of neurons[lower-alpha 1]	Intraspecific variation[lower-alpha 2]	Method[lower-alpha 3]	Sensory-associative structure	Binomial nomenclature	Image	Source
Common fruit fly	2,500*		Optical fractionator	Corpora pedunculata	Drosophila melanogaster		[63]
House cricket	50,000*		Optical fractionator	Corpora pedunculata	Acheta domesticus		[63]
Honey bee	170,000*		Optical fractionator	Corpora pedunculata	Genus: Apis		[63]
Common cockroach	200,000*		Optical fractionator	Corpora pedunculata	Genus: Periplaneta		[63]
African sheath-tailed bat	5,000,000		Isotropic fractionator	Pallium (cortex)	Coleura afra		[36]
Rufous trident bat	6,000,000		Isotropic fractionator	Pallium (cortex)	Triaenops persicus		[36]
Naked mole-rat	6,000,000	± 1,065,587[38]	Isotropic fractionator	Pallium (cortex)	Heterocephalus glaber		[35]
Little free-tailed bat	6,000,000		Isotropic fractionator	Pallium (cortex)	Chaerephon pumilus		[36]
Common bent-wing bat	6,000,000		Isotropic fractionator	Pallium (cortex)	Miniopterus schreibersii		[36]
Commerson's roundleaf bat	8,000,000		Isotropic fractionator	Pallium (cortex)	Hipposideros commersoni		[36]
Heart-nosed bat	10,000,000		Isotropic fractionator	Pallium (cortex)	Cardioderma cor		[36]
Ansell's mole-rat	10,000,000		Isotropic fractionator	Pallium (cortex)	Fukomys anselli		[41]
Smoky shrew	10,000,000	± 352,000[38]	Isotropic fractionator	Pallium (cortex)	Sorex fumeus		[38]
Short-palated fruit bat	10,000,000		Isotropic fractionator	Pallium (cortex)	Casinycteris argynnis		[36]
Mashona mole-rat	12,000,000		Isotropic fractionator	Pallium (cortex)	Fukomys darlingi		[41]
Woermann's bat	12,000,000		Isotropic fractionator	Pallium (cortex)	Megaloglossus woermanni		[36]
Northern short-tailed shrew	12,000,000	± 1,569,000[38]	Isotropic fractionator	Pallium (cortex)	Blarina brevicauda		[38]
Zenker's fruit bat	13,000,000		Isotropic fractionator	Pallium (cortex)	Scotonycteris zenkeri		[36]
House mouse	14,000,000	± 2,242,257[38]	Isotropic fractionator	Pallium (cortex)	Mus musculus		[38]
Hairy-tailed mole	16,000,000	± 2,611,000[38]	Isotropic fractionator	Pallium (cortex)	Parascalops breweri		[38]
Star-nosed mole	17,000,000	± 3,105,000[38]	Isotropic fractionator	Pallium (cortex)	Condylura cristata		[38]
Golden hamster	17,000,000	± 3,619,934[38]	Isotropic fractionator	Pallium (cortex)	Mesocricetus auratus		[38]
Damaraland mole-rat	21,000,000		Isotropic fractionator	Pallium (cortex)	Fukomys damarensis		[41]
Hottentot golden mole	22,000,000	± 2,154,000[38]	Isotropic fractionator	Pallium (cortex)	Amblysomus hottentotus		[38]
Gray mouse lemur	22,310,000		Isotropic fractionator	Pallium (cortex)	Microcebus murinus		[44]
Mechow's mole-rat	23,000,000		Isotropic fractionator	Pallium (cortex)	Fukomys mechowii		[41]
Franquet's epauletted fruit bat	23,000,000		Isotropic fractionator	Pallium (cortex)	Epomops franqueti		[36]
Hammer-headed bat	24,000,000		Isotropic fractionator	Pallium (cortex)	Hypsignathus mostrosus		[36]
Hedgehog	24,000,000^		Estimated	Pallium (cortex)	Subfamily Erinaceinae, various species		[64]
Silvery mole-rat	25,000,000		Isotropic fractionator	Pallium (cortex)	Heliophobius argenteocinereus		[41]
Wahlberg's epauletted fruit bat	26,000,000		Isotropic fractionator	Pallium (cortex)	Epomophorus wahlbergi		[36]
Cape mole-rat	26,000,000		Isotropic fractionator	Pallium (cortex)	Georychus capensis		[41]
Guyenne spiny rat	26,000,000	± 2,155,723[38]	Isotropic fractionator	Pallium (cortex)	Proechimys cayennensis		[38]
Eastern rock elephant shrew	26,000,000	± 4,020,000[38]	Isotropic fractionator	Pallium (cortex)	Elephantulus myurus		[38]
Eastern mole	27,000,000	± 5,113,000[38]	Isotropic fractionator	Pallium (cortex)	Scalopus aquaticus		[38]
Opossum	27,000,000^		Estimated	Pallium (cortex)	Didelphis virginiana		[64]
Egyptian fruit bat	29,000,000		Isotropic fractionator	Pallium (cortex)	Rousettus aegyptiacus		[36]
Brown Rat	31,000,000	+ 3,034,654[38]	Isotropic fractionator	Pallium (cortex)	Rattus norvegicus		[38]
Four-toed elephant shrew	34,000,000	± 5,840,000[38]	Isotropic fractionator	Pallium (cortex)	Petrodromus tetradactylus		[38]
Ferret	38,950,000		Isotropic fractionator	Pallium (cortex)	Mustela putorius furo		[46]
Cape dune mole-rat	43,000,000		Isotropic fractionator	Pallium (cortex)	Bathyergus suillus		[41]
Guinea pig	43,510,000	± 3,169,924[38]	Isotropic fractionator	Pallium (cortex)	Cavia porcellus		[35]
Eurasian blackcap	52,000,000		Isotropic fractionator	Pallium (DVR)	Sylvia atricapilla		[42]
Prairie dog	53,770,000	± 6,044,322[38]	Isotropic fractionator	Pallium (cortex)	Genus:Cynomys		[35]
Zebra finch	55,000,000		Isotropic fractionator	Pallium (DVR)	Taeniopygia guttata		[42]
Common treeshrew	60,000,000	± 26,510,000[38]	Isotropic fractionator	Pallium (cortex)	Tupaia glis		[38]
Red junglefowl	61,000,000		Isotropic fractionator	Pallium (DVR)	Gallus gallus		[42]
Goldcrest	64,000,000		Isotropic fractionator	Pallium (DVR)	Regulus regulus		[42]
European rabbit	71,450,000		Isotropic fractionator	Pallium (cortex)	Oryctolagus cuniculus		[35]
Rock dove	72,000,000		Isotropic fractionator	Pallium (DVR)	Columba livia		[42]
Eastern gray squirrel	77,330,000	± 2,634,444[38]	Isotropic fractionator	Pallium (cortex)	Sciurius carolinensis		[35]
Great tit	83,000,000		Isotropic fractionator	Pallium (DVR)	Parus major		[42]
Western tree hyrax	99,000,000		Isotropic fractionator	Pallium (cortex)	Dendrohyrax dorsalis		[38]
Green-rumped parrotlet	103,000,000		Isotropic fractionator	Pallium (DVR)	Forpus passerinus		[42]
Black-rumped agouti	113,000,000	± 2,576,768[38]	Isotropic fractionator	Pallium (cortex)	Dasyprocta prymnolopha		[1]
Banded mongoose	115,770,000		Isotropic fractionator	Pallium (cortex)	Mungos mungo		[46]
Common blackbird	136,000,000		Isotropic fractionator	Pallium (DVR)	Turdus merula		[42]
Budgerigar	149,000,000		Isotropic fractionator	Pallium (DVR)	Melopsittacus undulatus		[42]
Rock hyrax	198,000,000	± 29,082,000[38]	Isotropic fractionator	Pallium (cortex)	Procavia capensis		[38]
Northern greater galago	226,000,000	± 87,570,000[38]	Isotropic fractionator	Pallium (cortex)	Otolemur garnettii		[38]
Common starling	226,000,000		Isotropic fractionator	Pallium (DVR)	Sturnus vulgaris		[42]
Raccoon dog	240,180,000		Isotropic fractionator	Pallium (cortex)	Nyctereutes procyonoides		[49]
Common marmoset	245,000,000	± 81,180,000[38]	Isotropic fractionator	Pallium (cortex)	Callithrix jacchus		[38]
House cat	249,830,000		Isotropic fractionator	Pallium (cortex)	Felis catus or Felis silvestris catus		[46]
Brown bear	250,970,000		Isotropic fractionator	Pallium (cortex)	Ursus arctos		[46]
Cockatiel	258,000,000		Isotropic fractionator	Pallium (DVR)	Nymphicus hollandicus		[42]
Capybara	306,500,000	± 62,726,120[38]	Isotropic fractionator	Pallium (cortex)	Hydrochoerus hydrochaeris		[35]
Tarsius	310,000,000		Estimated	Pallium (cortex)	Genus: Tarsius, unknown species		[65]
Eastern rosella	333,000,000		Isotropic fractionator	Pallium (DVR)	Platycercus eximius		[42]
Red fox	355,010,000		Isotropic fractionator	Pallium (cortex)	Vulpes vulpes		[49]
Goeldi's marmoset	357,130,000		Isotropic fractionator	Pallium (cortex)	Callimico goeldii		[44]
Western grey kangaroo	370,170,000		Isotropic fractionator	Pallium (cortex)	Macropus fuliginosus		[66]
Golden jackal	393,620,000		Isotropic fractionator	Pallium (cortex)	Canis aureus		[49]
Monk parakeet	396,000,000		Isotropic fractionator	Pallium (DVR)	Myiopsitta monachus		[42]
Springbok	396,900,000		Isotropic fractionator	Pallium (cortex)	Antidorcas marsupialis		[50]
Azure-winged magpie	400,000,000		Isotropic fractionator	Pallium (DVR)	Cyanopica cyanus		[42]
Common hill myna	410,000,000		Isotropic fractionator	Pallium (DVR)	Gracula religiosa		[42]
Domesticated pig	425,000,000*		Optical fractionator	Pallium (cortex)	Sus scrofa domesticus		[67]
Barn owl	437,000,000		Isotropic fractionator	Pallium (DVR)	Tyto alba		[42]
Emu	439,000,000		Isotropic fractionator	Pallium (DVR)	Dromaius novaehollandiae		[42]
West Highland White Terrier	440,160,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris		[49]
Three-striped night monkey	442,000,000	± 111,310,000[38]	Isotropic fractionator	Pallium (cortex)	Aotus trivirgatus		[1]
Eurasian magpie	443,000,000		Isotropic fractionator	Pallium (DVR)	Pica pica		[42]
Raccoon	453,000,000		Isotropic fractionator	Pallium (cortex)	Procyon lotor		[68]
Chow Chow	471,500,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris		[49]
Western jackdaw	492,000,000		Isotropic fractionator	Pallium (DVR)	Coloeus monedula		[42]
Striped hyena	495,280,000		Isotropic fractionator	Pallium (cortex)	Hyaena hyaena		[46]
Chihuhua	513,330,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris		[49]
Eurasian jay	529,000,000		Isotropic fractionator	Pallium (DVR)	Garrulus glandarius		[42]
Lion	545,240,000		Isotropic fractionator	Pallium (cortex)	Panthera leo		[46]
Blesbok	570,670,000		Isotropic fractionator	Pallium (cortex)	Damaliscus pygargus phillipsi		[50]
Yorkshire Terrier	572,140,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris		[49]
Alexandrine parakeet	575,000,000		Isotropic fractionator	Pallium (DVR)	Psittacula eupatria		[42]
Tanimbar corella	599,000,000		Isotropic fractionator	Pallium (DVR)	Cacatua goffiniana		[42]
Golden retriever	627,000,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris		[46]
Gracile capuchin monkey	650,000,000^		Estimated	Pallium (cortex)	Genus: Cebus		[61]
Transylvanian Hound	725,760,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris		[49]
Greater kudu	762,570,000		Isotropic fractionator	Pallium (cortex)	Tragelaphus strepsiceros		[50]
Crab-eating macaque	800,960,000		Isotropic fractionator	Pallium (cortex)	Macaca fascicularis		[44]
Rook	820,000,000		Isotropic fractionator	Pallium (DVR)	Corvus frugilegus		[42]
Beagle	844,410,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris		[49]
Grey parrot	850,000,000		Isotropic fractionator	Pallium (DVR)	Psittacus erithacus		[42]
Komondor	883,380,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris		[49]
German Shepherd	885,460,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris		[49]
Sulphur-crested cockatoo	1,135,000,000		Isotropic fractionator	Pallium (DVR)	Cacatua galerita		[42]
Tufted capuchin	1,140,000,000		Isotropic fractionator	Pallium (cortex)	Sapajus apella		[38][1]
Harp seal	1,168,000,000^ 6,100,000,000*		Estimated Optical fractionator	Pallium (cortex)	Pagophilus groenlandicus		[69][70]
Horse	1,200,000,000*		Optical fractionator	Pallium (cortex)	Equus ferus caballus		[71]
Raven	1,204,000,000		Isotropic fractionator	Pallium (DVR)	Corvus corax		[42]
Kea	1,281,000,000		Isotropic fractionator	Pallium (DVR)	Nestor notabilis		[42]
Common squirrel monkey	1,340,000,000	± 20,000,000[38]	Isotropic fractionator	Pallium (cortex)	Saimiri sciureus		[38]
Bonnet macaque	1,660,000,000		Isotropic fractionator	Pallium (cortex)	Macaca radiata		[44]
Rhesus macaque	1,710,000,000		Isotropic fractionator	Pallium (cortex)	Macaca mulatta		[38]
Giraffe	1,731,000,000		Isotropic fractionator	Pallium (cortex)	Giraffa camelopardalis		[50]
Blue and yellow macaw	1,900,000,000		Isotropic fractionator	Pallium (DVR)	Ara ararauna		[42]
Pygmy sperm whale	2,020,000,000*		Optical fractionator	Pallium (cortex)	Kogia breviceps		[72]
Leopard seal	2,386,000,000^		Estimated	Pallium (cortex)	Hydrurga leptonyx		[69]
Guenon	2,500,000,000^		Estimated	Pallium (cortex)	Genus: Cercopithecus, unknown species		[65]
Pigtail Macaque	2,531,000,000^		Estimated	Pallium (cortex)	Macaca nemestrina		[69]
Gelada baboon	2,568,000,000^		Estimated	Pallium (cortex)	Theropithecus gelada		[69]
Red-and-green macaw	2,646,000,000^		Estimated	Pallium (DVR)	Ara chloropterus		[69]
Harbor porpoise	2,750,000,000*		Optical fractionator	Pallium (cortex)	Phocoena phocoena		[69][70]
Yellow baboon	2,880,000,000		Isotropic fractionator	Pallium (cortex)	Papio cynocephalus		[44]
Hyacinth macaw	2,944,000,000^		Estimated	Pallium (DVR)	Anodorhynchus hyacinthinus		[69]
Hamadryas baboon	2,990,000,000^		Estimated	Pallium (cortex)	Papio hamadryas		[69]
Mandrill	3,102,000,000^		Estimated	Pallium (cortex)	Mandrillus sphinx		[69]
Walrus	3,929,000,000^		Estimated	Pallium (cortex)	Odobenus rosmarus		[69]
Southern elephant seal	3,994,000,000^		Estimated	Pallium (cortex)	Mirounga leonina		[69]
African elephant	5,600,000,000		Isotropic fractionator	Pallium (cortex)	Loxodonta africana		[56]
Short-beaked common dolphin	6,700,000,000*		Optical fractionator	Pallium (cortex)	Delphinus delphis		[69][72]
Asian elephant	6,775,000,000^		Estimated	Pallium (cortex)	Elephas maximus		[69]
Pygmy chimpanzee or bonobo	7,250,000,000^		Estimated	Pallium (cortex)	Pan paniscus		[69]
Chimpanzee	7,400,000,000*		Optical fractionator	Pallium (cortex)	Pan troglodytes		[73]
Orangutan	7,704,000,000^ - 8,900,000,000^		Estimated	Pallium (cortex)	Genus: Pongo		[69][52]
Western gorilla	9,100,000,000^		Estimated	Pallium (cortex)	Gorilla gorilla		[69][52]
Cuvier's beaked whale	9,100,000,000*		Optical fractionator	Pallium (cortex)	Ziphius cavirostris		[72]
Beluga whale	10,000,000,000^		Estimated	Pallium (cortex)	Delphinapterus leucas		[69]
Bottlenose dolphin	12,700,000,000*		Optical fractionator	Pallium (cortex)	Tursiops truncatus		[69][72]
Common minke whale	12,800,000,000*		Optical fractionator	Pallium (cortex)	Balaenoptera acutorostrata		[74]
Fin whale	15,000,000,000*		Optical fractionator	Pallium (cortex)	Balaenoptera physalus		[69][75]
Blue whale	15,000,000,000^		Estimated	Pallium (cortex)	Balaenoptera musculus		[69]
Human	16,340,000,000 21,000,000,000*	± 2,170,000,000[38]	Isotropic fractionator Optical fractionator	Pallium (cortex)	Homo sapiens		[38][53][1][76][77]
Risso's dolphin	18,750,000,000^		Estimated	Pallium (cortex)	Grampus griseus		[69]
Short-finned pilot whale	35,000,000,000^		Estimated	Pallium (cortex)	Globicephala macrorhynchus		[69]
Long-finned pilot whale	37,200,000,000*		Optical fractionator	Pallium (cortex)	Globicephala melas		[78]
Killer whale	43,100,000,000*		Optical fractionator	Pallium (cortex)	Orcinus orca		[69][72]

See also

Lists of animals Brain size Brain-to-body mass ratio Encephalization quotient

Connectome Connectomics Cranial capacity Noogenesis

Notes

1. ^ = Estimated
   • = Optical fractionator
2. ± standard deviation
3. For the estimated values, the number of cortical neurons estimated from brain mass for different mammalian and bird orders are based on correlation observed between number of cortical neuron and brain mass per order[62]

References

1. Herculano-Houzel, Suzana (9 November 2009). "The human brain in numbers: a linearly scaled-up primate brain". Frontiers in Human Neuroscience. 3: 31. doi:10.3389/neuro.09.031.2009. PMC 2776484. PMID 19915731.
2. https://www.theguardian.com/science/blog/2012/feb/28/how-many-neurons-human-brain
3. Sherwood L, Klandorf H and Yancey P (2012) Animal Physiology: From Genes to Organisms Cengage Learning, p. 150. ISBN 9781133709510.
4. https://www.youtube.com/watch?v=z4eqSl7Vups
5. Schierwater B (December 2005). "My favorite animal, Trichoplax adhaerens". BioEssays. 27 (12): 1294–1302. doi:10.1002/bies.20320. PMID 16299758.
6. Ware, Randle W.; LoPresti, Vincent (1975). "Three-dimensional reconstruction from serial sections". Int. Rev. Cytol. International Review of Cytology. 40: 325–440. doi:10.1016/S0074-7696(08)60956-0. ISBN 9780123643407. PMID 1097356.
7. Martin C, Gross V, Hering L, Mayer G (2017). "The nervous and visual systems of onychophorans and tardigrades: learning about arthropod evolution from their closest relatives". Journal of Comparative Physiology A. 203 (8): 565–590. doi:10.1007/s00359-017-1186-4. PMID 28600600. S2CID 25280904.
8. Ryan, Kerrianne; Lu, Zhiyuan; Meinertzhagen, Ian A. (2016). "The CNS connectome of a tadpole larva of Ciona intestinalis (L.) highlights sidedness in the brain of a chordate sibling". eLife. 2016, 5:e16962: e16962. doi:10.7554/eLife.16962. PMC 5140270. PMID 27921996.
9. Ryan, Kerrianne; Lu, Zhiyuan; Meinertzhagen, Ian A. (2018). "The peripheral nervous system of the ascidian tadpole larva: Types of neurons and their synaptic networks". Journal of Comparative Neurology. 526 (4): 583–608. doi:10.1002/cne.24353. PMID 29124768. S2CID 20052591.
10. White JG, Southgate E, Thomson JN, Brenner S (November 1986). "The structure of the nervous system of the nematode Caenorhabditis elegans". Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. 314 (1165): 1–340. Bibcode:1986RSPTB.314....1W. doi:10.1098/rstb.1986.0056. PMID 22462104.
11. White JG (June 2013). "Getting into the mind of a worm--a personal view". WormBook: 1–10. doi:10.1895/wormbook.1.158.1. PMC 4781474. PMID 23801597.
12. Jabr F (2012-10-02). "The Connectome Debate: Is Mapping the Mind of a Worm Worth It?". Scientific American. Retrieved 2014-01-18.
13. White, J. G; E. Southgate; J. N Thomson; S. Brenner (1986-11-12). "The Structure of the Nervous System of the Nematode Caenorhabditis Elegans". Philosophical Transactions of the Royal Society B. 314 (1165): 1–340. Bibcode:1986RSPTB.314....1W. doi:10.1098/rstb.1986.0056. ISSN 0962-8436. PMID 22462104. S2CID 5006466.
14. Bode, H.; Berking, S.; David, C. N.; Gierer, A.; Schaller, H.; Trenkner, E. (1973). "Quantitative analysis of cell types during growth and morphogenesis in Hydra". Wilhelm Roux Archiv für Entwicklungsmechanik der Organismen (Submitted manuscript). 171 (4): 269–285. doi:10.1007/BF00577725. ISSN 0949-944X. PMID 28304608. S2CID 5484431.
15. Polilov, Alexey A. (2011). "The smallest insects evolve anucleate neurons". Arthropod Structure & Development. 41 (1): 29–34. doi:10.1016/j.asd.2011.09.001. PMID 22078364.
16. Garm, A.; Poussart, Y.; Parkefelt, L.; Ekström, P.; Nilsson, D-E. (2007). "The ring nerve of the box jellyfish Tripedalia cystophora". Cell and Tissue Research. 329 (1): 147–157. doi:10.1007/s00441-007-0393-7. ISSN 0302-766X. PMID 17340150. S2CID 26982210.
17. Kuffler SW, Potter DD (1964). "Glia in the leech central nervous system: physiological properties and neuron-glia relationship". J. Neurophysiol. 27 (2): 290–320. doi:10.1152/jn.1964.27.2.290. PMID 14129773.
18. Roth G, Dicke U (May 2005). "Evolution of the brain and intelligence". Trends Cogn. Sci. (Regul. Ed.). 9 (5): 250–7. doi:10.1016/j.tics.2005.03.005. PMID 15866152. S2CID 14758763. as PDF Archived 2009-07-31 at the Wayback Machine
19. Cash D, Carew TJ (1989). "A quantitative analysis of the development of the central nervous system in juvenile Aplysia californica". J Neurobiol. 20 (1): 25–47. doi:10.1002/neu.480200104. PMID 2921607.CS1 maint: uses authors parameter (link)
20. Roth, Gerhard (3 June 2013). The Long Evolution of Brains and Minds. Springer Science & Business Media. p. 121. ISBN 978-94-007-6259-6. Retrieved 9 December 2015.
21. Aniszewski, Tadeusz (25 April 2015). Alkaloids: Chemistry, Biology, Ecology, and Applications. Elsevier Science. p. 316. ISBN 978-0-444-59462-4. Retrieved 9 December 2015.
22. Scientists Capture All The Neurons Firing Across A Fish's Brain On Video Popular Science, 19 March 2013.
23. "Anatomy & Biology". The Lobster Institute. University of Maine. Archived from the original on February 8, 2018. Retrieved March 19, 2016.
24. https://www.wired.com/story/most-complete-brain-map-ever-is-here-a-flys-connectome/
25. Lagercrantz, Hugo; Hanson, M. A.; Ment, Laura R.; Peebles, Donald M., eds. (7 January 2010). The Newborn Brain: Neuroscience and Clinical Applications. Cambridge University Press. p. 3. ISBN 978-1-139-48558-6. Retrieved 9 December 2015.
26. Nass, Richard; Przedborski, Serge (28 April 2011). Parkinson's Disease: molecular and therapeutic insights from model systems. Academic Press. p. 325. ISBN 978-0-08-055958-2. Retrieved 9 December 2015.
27. John and Sarah Tefl. "Interesting Facts About Ants". Retrieved December 23, 2010.
28. Menzel R, Giurfa M (February 2001). "Cognitive architecture of a mini-brain: the honeybee". Trends Cogn. Sci. 5 (2): 62–71. doi:10.1016/S1364-6613(00)01601-6. PMID 11166636. S2CID 3202685.
29. "A Strange Approach to Social Interaction, and Butterflies". Anthropology.net. January 10, 2007. Archived from the original on January 13, 2007. Retrieved November 26, 2010.
30. Storks, Levi; Powell, Brian J.; Leal, Manuel (2020). "Peeking inside the lizard brain: Neuron numbers in Anolis and its implications for cognitive performance and vertebrate brain evolution". Integrative and Comparative Biology. doi:10.1093/icb/icaa129. PMID 33175153.
31. Marhounová, Lucie; Kotrschal, Alexander; Kverková, Kristina; Kolm, Niclas; Němec, Pavel (2019). "Artificial selection on brain size leads to matching changes in overall number of neurons". Evolution. 0 (9): 2003–2012. doi:10.1111/evo.13805. ISSN 1558-5646. PMC 6772110. PMID 31339177.
32. Kverková, Kristina; Polonyiová, Alexandra; Kubička, Lukáš; Němec, Pavel (2020-09-30). "Individual and age-related variation of cellular brain composition in a squamate reptile". Biology Letters. 16 (9): 20200280. doi:10.1098/rsbl.2020.0280. PMC 7532707. PMID 32961085.
33. Hinsch, K. & Zupanc, G. K. H. (2007). "Generation and long-term persistence of new neurons in the adult zebrafish brain: A quantitative analysis". Neuroscience. 146 (2): 679–696. doi:10.1016/j.neuroscience.2007.01.071. PMID 17395385. S2CID 5643696.
34. "Frog Brain Neuron Number". Archived from the original on 16 July 2015. Retrieved 15 July 2015.
35. Herculano-Houzel, Suzana; Ribeiro, Pedro; Campos, Leandro; Silva, Alexandre Valotta da; Torres, Laila B.; Catania, Kenneth C.; Kaas, Jon H. (2011). "Updated Neuronal Scaling Rules for the Brains of Glires (Rodents/Lagomorphs)". Brain, Behavior and Evolution. 78 (4): 302–314. doi:10.1159/000330825. ISSN 0006-8977. PMC 3237106. PMID 21985803.
36. Herculano‐Houzel, Suzana; Cunha, Felipe Barros da; Reed, Jamie L.; Kaswera‐Kyamakya, Consolate; Gillissen, Emmanuel; Manger, Paul R. (2020). "Microchiropterans have a diminutive cerebral cortex, not an enlarged cerebellum, compared to megachiropterans and other mammals". Journal of Comparative Neurology. n/a (n/a): 2978–2993. doi:10.1002/cne.24985. ISSN 1096-9861. PMID 32656795. S2CID 220499352.
37. Hofman, Michel A.; Falk, Dean (2 March 2012). Evolution of the Primate Brain: From Neuron to Behavior. Elsevier. p. 425. ISBN 978-0-444-53860-4.
38. name="H-Houzel2015"Herculano-Houzel, Suzana; Catania, Kenneth; Manger, Paul R.; Kaas, Jon H. (2015). "Mammalian Brains Are Made of These: A Dataset of the Numbers and Densities of Neuronal and Nonneuronal Cells in the Brain of Glires, Primates, Scandentia, Eulipotyphlans, Afrotherians and Artiodactyls, and Their Relationship with Body Mass" (PDF). Brain, Behavior and Evolution. S. Karger AG. 86 (3–4): 145–163. doi:10.1159/000437413. ISSN 0006-8977. PMID 26418466. S2CID 10637829.
39. Herculano-Houzel S, Mota B, Lent R (2006). "Cellular scaling rules for rodent brains". Proc Natl Acad Sci USA. 103 (32): 12138–12143. Bibcode:2006PNAS..10312138H. doi:10.1073/pnas.0604911103. PMC 1567708. PMID 16880386.
40. Ngwenya, Ayanda; Patzke, Nina; Manger, Paul R.; Herculano-Houzel, Suzana (2016). "Continued Growth of the Central Nervous System without Mandatory Addition of Neurons in the Nile Crocodile (Crocodylus niloticus)". Brain, Behavior and Evolution. 87 (1): 19–38. doi:10.1159/000443201. PMID 26914769. S2CID 5353731.
41. Kverková, Kristina; Bělíková, Tereza; Olkowicz, Seweryn; Pavelková, Zuzana; O’Riain, M. Justin; Šumbera, Radim; Burda, Hynek; Bennett, Nigel C.; Němec, Pavel (2018-06-15). "Sociality does not drive the evolution of large brains in eusocial African mole-rats". Scientific Reports. 8 (1): 9203. Bibcode:2018NatSR...8.9203K. doi:10.1038/s41598-018-26062-8. ISSN 2045-2322. PMC 6003933. PMID 29907782.
42. Olkowicz, Seweryn; Kocourek, Martin; Lučan, Radek K.; Porteš, Michal; Fitch, W. Tecumseh; Herculano-Houzel, Suzana; Němec, Pavel (2016). "Birds have primate-like numbers of neurons in the forebrain". Proceedings of the National Academy of Sciences. 113 (26): 7255–60. doi:10.1073/pnas.1517131113. ISSN 0027-8424. PMC 4932926. PMID 27298365.
43. Herculano-Houzel, S. & Lent, R. (2005). "Isotropic fractionator: a simple, rapid method for the quantification of total cell and neuron numbers in the brain". J Neurosci. 25 (10): 2518–2521. doi:10.1523/jneurosci.4526-04.2005. PMC 6725175. PMID 15758160.
44. Gabi, Mariana; Collins, Christine E.; Wong, Peiyan; Torres, Laila B.; Kaas, Jon H.; Herculano-Houzel, Suzana (2010). "Cellular Scaling Rules for the Brains of an Extended Number of Primate Species". Brain, Behavior and Evolution. 76 (1): 32–44. doi:10.1159/000319872. ISSN 0006-8977. PMC 2980814. PMID 20926854.
45. Herculano-Houzel S, Collins C, Wong P, Kaas J (2007). "Cellular scaling rules for primate brains". Proc Natl Acad Sci USA. 104 (9): 3562–3567. Bibcode:2007PNAS..104.3562H. doi:10.1073/pnas.0611396104. PMC 1805542. PMID 17360682.
46. Jardim-Messeder, Débora; Lambert, Kelly; Noctor, Stephen; Pestana, Fernanda M.; Leal, de Castro; E, Maria; Bertelsen, Mads F.; Alagaili, Abdulaziz N.; Mohammad, Osama B. (2017). "Dogs Have the Most Neurons, Though Not the Largest Brain: Trade-Off between Body Mass and Number of Neurons in the Cerebral Cortex of Large Carnivoran Species". Frontiers in Neuroanatomy. 11: 118. doi:10.3389/fnana.2017.00118. ISSN 1662-5129. PMC 5733047. PMID 29311850.
47. "Brain Facts and Figures". Retrieved 15 July 2015.
48. Ananthanarayanan, Rajagopal; Esser, Steven K.; Simon, Horst D.; Modha, Dharmendra S. (2009). "The cat is out of the bag: cortical simulations with 10⁹ neurons, 10¹³ synapses". Proceedings of the Conference on High Performance Computing Networking, Storage and Analysis - SC '09. pp. 1–12. doi:10.1145/1654059.1654124. ISBN 978-1-60558-744-8. S2CID 6110450.
49. Salajková, Veronika (2020-02-03). "Pravidla buněčného škálování mozku u psů: Efekt domestikace a miniaturizace psích plemen" (in Czech). Cite journal requires |journal= (help)
50. Kazu, Rodrigo S.; Maldonado, José; Mota, Bruno; Manger, Paul R.; Herculano-Houzel, Suzana (2015). "Corrigendum: Cellular scaling rules for the brain of Artiodactyla include a highly folded cortex with few neurons". Frontiers in Neuroanatomy. 9: 39. doi:10.3389/fnana.2015.00039. ISSN 1662-5129. PMC 4374476. PMID 25859187.
51. Herculano-Houzel, Suzana (June 2012). "The remarkable, yet not extraordinary, human brain as a scaled-up primate brain and its associated cost". Proceedings of the National Academy of Sciences. 109 Suppl 1: 10661–8. doi:10.1073/pnas.1201895109. PMC 3386878. PMID 22723358.
52. Herculano-Houzel, Suzana; Kaas, Jon (2011). "Gorilla and Orangutan Brains Conform to the Primate Cellular Scaling Rules: Implications for Human Evolution". Brain Behav Evol. 77 (1): 33–44. doi:10.1159/000322729. PMC 3064932. PMID 21228547.
53. Azevedo, Frederico A.C.; Carvalho, Ludmila R.B.; Grinberg, Lea T.; Farfel, José Marcelo; Ferretti, Renata E.L.; Leite, Renata E.P.; Filho, Wilson Jacob; Lent, Roberto; Herculano-Houzel, Suzana (2009). "Equal numbers of neuronal and nonneuronal cells make the human brain an isometrically scaled-up primate brain". The Journal of Comparative Neurology. 513 (5): 532–541. doi:10.1002/cne.21974. PMID 19226510. S2CID 5200449.
54. Herculano-Houzel, S. (20 June 2012). "The remarkable, yet not extraordinary, human brain as a scaled-up primate brain and its associated cost". Proceedings of the National Academy of Sciences. 109 (Supplement_1): 10661–10668. doi:10.1073/pnas.1201895109. PMC 3386878. PMID 22723358.
55. TOWER DB. (1954). "Structural and functional organization of mammalian cerebral cortex; the correlation of neurone density with brain size; cortical neurone density in the fin whale (Balaenoptera physalus L.) with a note on the cortical neurone density in the Indian elephant". The Journal of Comparative Neurology. 101 (1): 19–51. doi:10.1002/cne.901010103. PMID 13211853. S2CID 10396499.
56. Herculano-Houzel, S; Avelino-de-Souza, K; Neves, K; Porfírio, J; Messeder, D; Mattos Feijó, L; Maldonado, J; Manger, PR (2014). "The Elephant Brain in Numbers". Front Neuroanat. 8: 46. doi:10.3389/fnana.2014.00046. PMC 4053853. PMID 24971054.
57. "Searching For The Elephant's Genius Inside the Largest Brain on Land". Scientificamerica. 26 February 2014.
58. MacLean, P.D. (Jan 31, 1990). The Triune Brain in Evolution: Role in Paleocerebral Functions. Springer Science & Business Media. p. 10. ISBN 9780306431685. Retrieved 21 May 2020.
59. Finger, Thomas E.; Yamamoto, Naoyuki; Karten, Harvey J.; Hof, Patrick R. (2013). "Evolution of the forebrain — revisiting the pallium". Journal of Comparative Neurology. Wiley Periodicals, Inc. 521 (16): 3601–3603. doi:10.1002/cne.23444. PMID 23893869. S2CID 5062781.
60. Tomer, Raju; Denes, Alexandru S.; Tessmar-Raible, Kristin; Arendt, Detlev (September 3, 2010). "Profiling by Image Registration Reveals Common Origin of Annelid Mushroom Bodies and Vertebrate Pallium". Cell. 142 (5): 800–809. doi:10.1016/j.cell.2010.07.043. PMID 20813265. S2CID 917306.
61. Hofman, Michel A.; Falk, Dean (2 March 2012). Evolution of the Primate Brain: From Neuron to Behavior. Elsevier. p. 424. ISBN 978-0-444-53867-3.
63. Heisenberg, Martin (May 1998). "What Do the Mushroom Bodies Do for the Insect Brain? An Introduction". Learning & Memory. 5 (1): 1–10. PMC 311238. PMID 10454369.
64. Fasolo, Aldo (30 November 2011). The Theory of Evolution and Its Impact. Springer. p. 182. ISBN 978-88-470-1973-7.
65. Quarton, Gardner C.; Melnechuk, Theodore; Schmitt, Francis O. (1967). The neurosciences. Rockefeller University Press. p. 732. GGKEY:DF21HXQKLNX.
66. Dos Santos, S.E.; Porfirio, J.; da Cunha, F.B.; Manger, P.R.; Tavares, W.; Pessoa, L.; Raghanti, M.A.; Sherwood, C.C.; Herculano-Houzel, S. (2017). "Cellular scaling rules for the brains of marsupials: Not as "primitive" as expected". Brain, Behavior and Evolution. 89 (1): 48–63. doi:10.1159/000452856. PMID 28125804. Table S1: Cellular composition of the Marsupial brains.
67. "LEARNING FROM PIG BRAINS". Retrieved 15 July 2015.
68. Lambert KG, Bardi M, Landis T, Hyer MM, Rzucidlo A, Gehrt S, Anchor C, Jardim Messeder D, Herculano-Houzel S (2014). "Behind the Mask: Neurobiological indicants of emotional resilience and cognitive function in wild raccoons (Procyon lotor)". Society for Neuroscienc.
69. Herculano‐Houzel, Suzana (2019). "Longevity and sexual maturity vary across species with number of cortical neurons, and humans are no exception". Journal of Comparative Neurology. 527 (10): 1689–1705 Supporting Information Table S1. doi:10.1002/cne.24564. ISSN 0021-9967. PMID 30350858. S2CID 53033539.
70. Walløe, Solveig; Eriksen, Nina; Dabelsteen, Torben; Pakkenberg, Bente (2010-12-01). "A neurological comparative study of the harp seal (Pagophilus groenlandicus) and harbor porpoise (Phocoena phocoena) brain". Anatomical Record. 293 (12): 2129–2135. doi:10.1002/ar.21295. ISSN 1932-8494. PMID 21077171. S2CID 2636107.
71. Haug, Herbert (October 1987). "Brain sizes, surfaces, and neuronal sizes of the cortex cerebri: A stereological investigation of man and his variability and a comparison with some mammals (primates, whales, marsupials, insectivores, and one elephant)". American Journal of Anatomy. 180 (2): 126–142. doi:10.1002/aja.1001800203. ISSN 0002-9106. PMID 3673918.
72. Ridgway, Sam H.; Brownson, Robert H.; Alstyne, Kaitlin R. Van; Hauser, Robert A. (2019-12-16). "Higher neuron densities in the cerebral cortex and larger cerebellums may limit dive times of delphinids compared to deep-diving toothed whales". PLOS ONE. 14 (12): e0226206. Bibcode:2019PLoSO..1426206R. doi:10.1371/journal.pone.0226206. ISSN 1932-6203. PMC 6914331. PMID 31841529.
73. Kaas, Jon (4 January 2015). "Cortical cell and neuron density estimates in one chimpanzee hemisphere". PNAS. 113 (3): 740–5. doi:10.1073/pnas.1524208113. PMC 4725503. PMID 26729880.
74. Eriksen, Nina; Pakkenberg, Bente (2007-01-01). "Total neocortical cell number in the mysticete brain". Anatomical Record. 290 (1): 83–95. doi:10.1002/ar.20404. ISSN 1932-8486. PMID 17441201. S2CID 31374672.
75. Mammals, Food and Agriculture Organization of the United Nations Working Party on Marine (1978-01-01). Mammals in the Seas: Report. Food & Agriculture Org. ISBN 9789251005132.
76. Steven M. Platek; Julian Paul Keenan & Todd K. Shackelford (2009). "Evolutionary Cognitive Neuroscience" (PDF): 139. Cite journal requires |journal= (help)
77. Pakkenberg, Bente; Gunderson, Hans Jorgen G. (1997). "Neocortical neuron number in humans: Effect of sex and age". The Journal of Comparative Neurology. Wiley‐Liss, Inc. 384 (2): 312–320. doi:10.1002/(SICI)1096-9861(19970728)384:2<312::AID-CNE10>3.0.CO;2-K. PMID 9215725.
78. Mortensen HS, et al. (2014). "Quantitative relationships in delphinid neocortex". Front Neuroanat. 8: 132. doi:10.3389/fnana.2014.00132. PMC 4244864. PMID 25505387.