List of animals by number of neurons

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

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. The human brain contains 86 billion neurons, with 16 billion neurons in the cerebral cortex.

Scientists are engaged in counting, quantification, in order to find answers to the question in the strategy of neuroscience and intelligence of "self-knowledge": how the evolution of a set of components and parameters (~10¹¹ neurons, ~10¹⁴ synapses) of a complex system could lead to the phenomenon of the appearance of intelligence in the biological species "sapiens".

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
Trichoplax	0		Despite no nervous system, it exhibits coordinated feeding and response behaviors.
Asplanchna brightwellii (rotifer)	~200		Brain only
Tardigrade	~200		Brain only
Ciona intestinalis larva (sea squirt)	231	8,617 (central nervous system only)
Caenorhabditis elegans (roundworm)	302	~7,500	is the only organism to have its whole connectome (neuronal "wiring diagram") completed.
Starfish	~500		ring of neurons surrounding the mouth		*requires references
Jellyfish	5,600		Hydra vulgaris (H. attenuate)
Megaphragma mymaripenne	7,400
Box jellyfish	8,700–17,500		adult Tripedalia cystophora (8 mm diameter) – does not include 1000 neurons in each of the four rhopalia
Medicinal leech	10,000
Pond snail	11,000
Sea slug	18,000
Amphioxus	20,000		central nervous system only
Larval zebrafish	100,000
Lobster	100,000
Fruit fly	150,000		There are approximately 135,000 and 15,000 neurons in the brain and ventral nerve cord, respectively.		Drosophila connectome
Wandering spider	100,000
Calliopsis (bee)	234,000
Ant	250,000		Varies per species
Perdita (bee)	275,000
Melissodes	495,000
Bombus impatiens	557,000
Western honey bee	613,000
Honey bee	960,000	~1×10^9
Cockroach	1,000,000
Coconut crab	>1,000,000		c. 1,000,000 interneurons are dedicated to analysing olfactory input alone.
California carpenter bee	1,180,000
Steudner's dwarf gecko	1,771,000
Brown anole	2,792,000
Mochlus sundevallii	3,049,000
Peloponnese slowworm	3,713,000
Common house gecko	3,988,000
Takydromus sexlineatus	4,021,000
Anolis cristatellus	4,270,000
Papua snake lizard	4,271,000
Guppy	4,300,000
Natal Midlands dwarf chameleon	4,305,000
Acontias percivali	4,340,000
Sand lizard	4,341,000
Ocelot gecko	4,420,000
Darevskia raddei	4,765,000
Anolis evermanni	4,920,000
Echis carinatus	4,951,000
Cerastes cerastes	4,996,000
Tenerife gecko	5,001,000
Draco sumatranus	5,174,000
Blue-throated keeled lizard	5,269,000
Crested gecko	5,417,000
Lacerta strigata	5,529,000
San Francisco garter snake	5,663,000
Red-eyed crocodile skink	5,697,000
Emoia cyanura	5,733,000
East African spiny-tailed lizard	5,756,000
Chalcides ocellatus	5,774,000
Cylindrophis ruffus	5,779,000
Cat gecko	5,964,000
Aspidoscelis deppii	5,968,000
Brown water snake	5,995,000
Aspidelaps lubricus	6,020,000
Scincus scincus	6,284,000
Montivipera xanthina	6,677,000
Hispaniolan curlytail lizard	7,063,000
Sceloporus malachiticus	7,149,000
Crotalus durissus	7,263,000
Agama agama	7,455,000
Agama aculeata	7,631,000
Gekko kuhli	7,659,000
Leopard gecko	8,081,000
Latastia longicaudata	8,099,000
Razor-backed musk turtle	8,389,000
Greek tortoise	8,520,000
Phelsuma grandis	8,623,000
Acanthocercus atricollis	8,650,000
Tokay gecko	8,892,000
Russian tortoise	9,008,000
Marginated tortoise	9,074,000
Psammophis elegans	9,170,000
Xenopeltis unicolor	9,293,000
Zonosaurus Karsteni	9,538,000
Oplurus quadrimaculatus	9,565,000
Malagasy giant chameleon	9,751,000
Ahaetulla prasina	9,767,000
Dasia olivacea	9,785,000
Adult zebrafish	~10,000,000		cells (neurons + other)
Timon tangitanus	10,619,000
Corn snake	10,629,000
Acanthosaura capra	10,724,000
Gallotia galloti	10,903,000
Eutropis multifasciata	10,944,000
Rainbow boa	11,083,000
East African black mud turtle	11,285,000
Indochinese spitting cobra	11,306,000
Cyrtodactylus irianjayaensis	11,415,000
Uromastyx ornata	11,438,000
Yellow-throated plated lizard	11,847,000
Meller's chameleon	12,035,000
Twist-necked turtle	12,171,000
Western whiptail	12,269,000
Gehyra vorax	12,388,000
White-lipped mud turtle	12,671,000
Painted wood turtle	12,677,000
Sheltopusik	12,830,000
Standing's day gecko	13,223,000
Common snapping turtle	13,681,000
Painted turtle	14,302,000
Ocellated lizard	14,593,000
Oplurus cuvieri	14,627,000
African spurred tortoise	14,986,000
Boa imperator	15,194,000
Red-eared slider	15,388,000
Plumed basilisk	15,536,000
Red-bellied short-necked turtle	15,787,000
Frog	16,000,000
Corallus hortulana	16,303,000
Blue-tongued skink	16,376,000
Gran Canaria giant lizard	18,038,000
Chinese water dragon	18,301,000
Chlamydosaurus	18,641,000
Northern snake-necked turtle	19,040,000
Spiny-tailed monitor	19,771,000
Boa constrictor	19,781,000
Ameiva ameiva	19,835,000
Chinese softshell turtle	20,697,000
Amboina box turtle	21,440,000
Alligator snapping turtle	22,230,000
Yellow anaconda	23,035,000
Mexican beaded lizard	23,681,000
Major skink	24,155,000
Sudan plated lizard	24,434,000
Mata mata	26,105,000
Naked mole-rat	26,880,000
Weber's sailfin lizard	27,245,000
Green iguana	29,098,000
Argentine black and white tegu	29,251,000
Cyclura nubila	30,820,000
Gold tegu	31,335,000
Varanus macraei	33,091,000
Little free-tailed bat	35,000,000
Smoky shrew	36,000,000
Sand goanna	50,253,000
Short-tailed shrew	52,000,000
Pig-nosed turtle	53,027,000
Common bent-wing bat	56,000,000
African sheath-tailed bat	59,000,000
Hottentot golden mole	65,000,000
Woermann's bat	66,000,000
Zenker's fruit bat	66,000,000
Commerson's roundleaf bat	67,000,000
Rufous trident bat	70,000,000
House mouse	71,000,000	~1×10^12
Asian water monitor	78,231,000
King quail	80,478,000
Nile crocodile	80,500,000
Heart-nosed bat	81,000,000
Diamond dove	87,879,000
Golden hamster	90,000,000
Short-palated fruit bat	99,000,000
Ansell's mole-rat	103,000,000
Mashona mole-rat	113,000,000
Common quail	117,760,000
Hairy-tailed mole	124,000,000
Eastern rock elephant shrew	129,000,000
Star-nosed mole	131,000,000
Zebra finch	131,000,000		Brain only
African collared dove	139,271,000
Silvery mole-rat	148,000,000
Northern bobwhite	148,399,000
Four-toed elephant shrew	157,000,000
Eurasian blackcap	157,000,000
Wahlberg's epauletted fruit bat	162,000,000
Goldcrest	164,000,000
Cape mole-rat	170,000,000
Grey partridge	170,287,000
Egyptian fruit bat	172,000,000
Mechow's mole-rat	174,000,000
Damaraland mole-rat	178,000,000
Franquet's epauletted fruit bat	186,000,000
Brown rat	200,000,000	~4.48×10^11
Guyenne spiny rat	202,000,000
Eastern mole	204,000,000
Elegant crested tinamou	217,768,000
Red junglefowl	221,000,000
Great tit	226,000,000
Green-rumped parrotlet	227,000,000
Quebracho crested tinamou	235,671,000
Guinea pig	240,000,000
Chilean tinamou	241,374,000
Gray mouse lemur	254,710,000
Common wood pigeon	258,681,000
Common treeshrew	261,000,000
Hammer-headed bat	275,000,000
Wood duck	305,816,000
Pigeon	310,000,000		Brain only
Budgerigar	322,000,000
Pygmy falcon	350,367,000
Cape dune mole-rat	361,000,000
Mallard	367,000,000
Eurasian teal	375,409,000
Common blackbird	379,000,000
Marbled duck	386,920,000
Reeves's pheasant	387,173,000
Eurasian sparrowhawk	401,751,000
Ferret	404,000,000
Cockatiel	453,000,000
Gray squirrel	453,660,000
Banded mongoose	454,000,000
Prairie dog	473,940,000
Red-breasted goose	482,705,000
Common starling	483,000,000
Wild turkey	492,873,000
European rabbit	494,200,000
Octopus	500,000,000
Western tree hyrax	505,000,000
Eurasian pygmy owl	533,263,000
Indian peafowl	570,934,000
Victoria crowned pigeon	578,697,000
Little owl	585,923,000
Common kestrel	624,582,000
Common marmoset	636,000,000
Eastern rosella	642,000,000
Yellow-knobbed curassow	652,989,000
Barn owl	690,000,000
Monk parakeet	697,000,000
Greylag goose	738,232,000
Azure-winged magpie	741,000,000
Rock hyrax	756,000,000
Cat	760,000,000	~1×10^13
Black-rumped agouti	857,000,000
Magpie	897,000,000
Common hill myna	906,000,000
Northern greater galago	936,000,000
Western jackdaw	968,000,000
Long-eared owl	991,310,000
Mute swan	1.001×10^9
Common buzzard	1.001×10^9
Black vulture	1.009×10^9
Greater rhea	1.03×10^9
Eurasian jay	1.085×10^9
Alexandrine parakeet	1.096×10^9
Raccoon dog	1.16×10^9
Tanimbar corella	1.161×10^9
Saker falcon	1.204×10^9
Emu	1.335×10^9
Three-striped night monkey	1.468×10^9
Rook	1.509×10^9
Grey parrot	1.566×10^9
Tawny owl	1.58×10^9
Capybara	1.6×10^9
Common ostrich	1.62×10^9
White-tailed eagle	1.65×10^9
Jackal	1.73×10^9
Snowy owl	1.807×10^9
Eurasian eagle-owl	1.897×10^9
Fox	2.11×10^9
Sulphur-crested cockatoo	2.122×10^9
Raccoon	2.148×10^9
Kea	2.149×10^9
Raven	2.171×10^9		Brain only
Domestic pig	2.22×10^9
Dog	2.253×10^9
Chihuahua (dog)	2.51×10^9
Dog (Chow Chow)	2.61×10^9
Dog (Yorkshire Terrier)	2.64×10^9
Springbok	2.72×10^9
Dog (West Highland White Terrier)	2.83×10^9
Blesbok	3.06×10^9
Blue-and-yellow macaw	3.136×10^9		Brain only
Common squirrel monkey	3.246×10^9
Crab-eating macaque	3.44×10^9
Dog (German Shepherd)	3.53×10^9
Tufted capuchin	3.691×10^9
Bonnet macaque	3.78×10^9
Striped hyena	3.885×10^9
Dog (Komondor)	3.99×10^9
Dog (Transylvanian Hound)	4.39×10^9
Lion	4.667×10^9
Greater kudu	4.91×10^9
Rhesus macaque	6.376×10^9
Brown bear	9.586×10^9
Giraffe	1.075×10^10
Yellow baboon	1.095×10^10
Chimpanzee	2.8×10^10
Orangutan	3.26×10^10
Gorilla	3.34×10^10
Human	8.6×10^10	~1.5×10^14	Neurons for average adult
African elephant	2.57×10^11

List of animal species by forebrain (cerebrum or pallium) neuron number

The question of what physical characteristic of an animal makes an animal intelligent has varied over the centuries. One early speculation was brain size (or weight, which provides the same ordering.) A second proposal was brain-to-body-mass ratio, and a third was encephalization quotient, sometimes referred to as EQ. The current best predictor is number of neurons in the forebrain, based on Herculano-Houzel's improved neuron counts. It accounts most accurately for variations in dependence on the cerebellum. The elephant depends on its exceptionally large cerebellum, while birds make do with a much smaller one.

Differing methods have been used to count neurons and these may differ in degree of reliability. These are the optical fractionator, an application of stereology and the isotropic fractionator, a recent methodological innovation. Most numbers in the list are the result of studies using the newer isotropic fractionator. A variation of the optical fractionator was responsible for the previous total human brain neuron count of 100,000,000,000 neurons, which has been revised down to 86,000,000,000 by the use of the isotropic fractionator. This is in part why it may be considered to be less reliable. Finally, some numbers are the result of estimations based on correlations observed between number of cortical neurons and brain mass within closely related taxa.

The following table gives information on the number of neurons estimated to be in the sensory-associative structure: the cerebral cortex (aka pallium) for mammals, the dorsal ventricular ridge ("DVR" or "hypopallium") of the pallium for birds, and the corpora pedunculata ("mushroom bodies") for insects.

Common name	Average number of sensory-associative structure neurons	Intraspecific variation	Method	Sensory-associative structure	Binomial nomenclature	Image	Source
Common fruit fly	2,500*		Optical fractionator	Corpora pedunculata	Drosophila melanogaster
House cricket	50,000*		Optical fractionator	Corpora pedunculata	Acheta domesticus
Honey bee	170,000*		Optical fractionator	Corpora pedunculata	Genus: Apis
Common cockroach	200,000*		Optical fractionator	Corpora pedunculata	Genus: Periplaneta
African sheath-tailed bat	5,000,000		Isotropic fractionator	Pallium (cortex)	Coleura afra
Rufous trident bat	6,000,000		Isotropic fractionator	Pallium (cortex)	Triaenops persicus
Naked mole-rat	6,000,000	± 1,065,587	Isotropic fractionator	Pallium (cortex)	Heterocephalus glaber
Little free-tailed bat	6,000,000		Isotropic fractionator	Pallium (cortex)	Chaerephon pumilus
Common bent-wing bat	6,000,000		Isotropic fractionator	Pallium (cortex)	Miniopterus schreibersii
Commerson's roundleaf bat	8,000,000		Isotropic fractionator	Pallium (cortex)	Hipposideros commersoni
Heart-nosed bat	10,000,000		Isotropic fractionator	Pallium (cortex)	Cardioderma cor
Ansell's mole-rat	10,000,000		Isotropic fractionator	Pallium (cortex)	Fukomys anselli
Smoky shrew	10,000,000	± 352,000	Isotropic fractionator	Pallium (cortex)	Sorex fumeus
Short-palated fruit bat	10,000,000		Isotropic fractionator	Pallium (cortex)	Casinycteris argynnis
Mashona mole-rat	12,000,000		Isotropic fractionator	Pallium (cortex)	Fukomys darlingi
Woermann's bat	12,000,000		Isotropic fractionator	Pallium (cortex)	Megaloglossus woermanni
Northern short-tailed shrew	12,000,000	± 1,569,000	Isotropic fractionator	Pallium (cortex)	Blarina brevicauda
Zenker's fruit bat	13,000,000		Isotropic fractionator	Pallium (cortex)	Scotonycteris zenkeri
House mouse	14,000,000	± 2,242,257	Isotropic fractionator	Pallium (cortex)	Mus musculus
Hairy-tailed mole	16,000,000	± 2,611,000	Isotropic fractionator	Pallium (cortex)	Parascalops breweri
Star-nosed mole	17,000,000	± 3,105,000	Isotropic fractionator	Pallium (cortex)	Condylura cristata
Golden hamster	17,000,000	± 3,619,934	Isotropic fractionator	Pallium (cortex)	Mesocricetus auratus
Diamond dove	18,209,000		Isotropic fractionator	Pallium (DVR)	Geopelia cuneata
King quail	20,523,000		Isotropic fractionator	Pallium (DVR)	Synoicus chinensis
Damaraland mole-rat	21,000,000		Isotropic fractionator	Pallium (cortex)	Fukomys damarensis
Hottentot golden mole	22,000,000	± 2,154,000	Isotropic fractionator	Pallium (cortex)	Amblysomus hottentotus
Gray mouse lemur	22,310,000		Isotropic fractionator	Pallium (cortex)	Microcebus murinus
Common quail	22,568,000		Isotropic fractionator	Pallium (DVR)	Coturnix coturnix
Mechow's mole-rat	23,000,000		Isotropic fractionator	Pallium (cortex)	Fukomys mechowii
Franquet's epauletted fruit bat	23,000,000		Isotropic fractionator	Pallium (cortex)	Epomops franqueti
Hammer-headed bat	24,000,000		Isotropic fractionator	Pallium (cortex)	Hypsignathus mostrosus
Hedgehog	24,000,000^		Estimated	Pallium (cortex)	Subfamily Erinaceinae, various species
Silvery mole-rat	25,000,000		Isotropic fractionator	Pallium (cortex)	Heliophobius argenteocinereus
Wahlberg's epauletted fruit bat	26,000,000		Isotropic fractionator	Pallium (cortex)	Epomophorus wahlbergi
Cape mole-rat	26,000,000		Isotropic fractionator	Pallium (cortex)	Georychus capensis
Guyenne spiny rat	26,000,000	± 2,155,723	Isotropic fractionator	Pallium (cortex)	Proechimys cayennensis
Eastern rock elephant shrew	26,000,000	± 4,020,000	Isotropic fractionator	Pallium (cortex)	Elephantulus myurus
Eastern mole	27,000,000	± 5,113,000	Isotropic fractionator	Pallium (cortex)	Scalopus aquaticus
Opossum	27,000,000^		Estimated	Pallium (cortex)	Didelphis virginiana
Egyptian fruit bat	29,000,000		Isotropic fractionator	Pallium (cortex)	Rousettus aegyptiacus
Brown Rat	31,000,000	+ 3,034,654	Isotropic fractionator	Pallium (cortex)	Rattus norvegicus
Four-toed elephant shrew	34,000,000	± 5,840,000	Isotropic fractionator	Pallium (cortex)	Petrodromus tetradactylus
Grey partridge	36,882,000		Isotropic fractionator	Pallium (DVR)	Perdix perdix
Ferret	38,950,000		Isotropic fractionator	Pallium (cortex)	Mustela putorius furo
Northern bobwhite	39,112,000		Isotropic fractionator	Pallium (DVR)	Colinus virginianus
African collared dove	39,997,000		Isotropic fractionator	Pallium (DVR)	Streptopelia roseogrisea
Cape dune mole-rat	43,000,000		Isotropic fractionator	Pallium (cortex)	Bathyergus suillus
Guinea pig	43,510,000	± 3,169,924	Isotropic fractionator	Pallium (cortex)	Cavia porcellus
Quebracho crested tinamou	48,292,000		Isotropic fractionator	Pallium (DVR)	Eudromia formosa
Common wood pigeon	51,325,000		Isotropic fractionator	Pallium (DVR)	Columba palumbus
Elegant crested tinamou	51,384,000		Isotropic fractionator	Pallium (DVR)	Eudromia elegans
Eurasian blackcap	52,000,000		Isotropic fractionator	Pallium (DVR)	Sylvia atricapilla
Prairie dog	53,770,000	± 6,044,322	Isotropic fractionator	Pallium (cortex)	Genus:Cynomys
Zebra finch	55,000,000		Isotropic fractionator	Pallium (DVR)	Taeniopygia guttata
Chilean tinamou	59,130,000		Isotropic fractionator	Pallium (DVR)	Nothoprocta perdicaria
Common treeshrew	60,000,000	± 26,510,000	Isotropic fractionator	Pallium (cortex)	Tupaia glis
Red junglefowl	61,000,000		Isotropic fractionator	Pallium (DVR)	Gallus gallus
Goldcrest	64,000,000		Isotropic fractionator	Pallium (DVR)	Regulus regulus
European rabbit	71,450,000		Isotropic fractionator	Pallium (cortex)	Oryctolagus cuniculus
Rock dove	72,000,000		Isotropic fractionator	Pallium (DVR)	Columba livia
Eastern gray squirrel	77,330,000	± 2,634,444	Isotropic fractionator	Pallium (cortex)	Sciurius carolinensis
Reeves's pheasant	80,688,000		Isotropic fractionator	Pallium (DVR)	Syrmaticus reevesii
Great tit	83,000,000		Isotropic fractionator	Pallium (DVR)	Parus major
Eurasian sparrowhawk	87,832,000		Isotropic fractionator	Pallium (DVR)	Accipiter nisus
Western tree hyrax	99,000,000		Isotropic fractionator	Pallium (cortex)	Dendrohyrax dorsalis
Green-rumped parrotlet	103,000,000		Isotropic fractionator	Pallium (DVR)	Forpus passerinus
Wild turkey	105,654,000		Isotropic fractionator	Pallium (DVR)	Meleagris gallopavo
Mallard	112,255,000		Isotropic fractionator	Pallium (DVR)	Anas platyrhynchos
Black-rumped agouti	113,000,000	± 2,576,768	Isotropic fractionator	Pallium (cortex)	Dasyprocta prymnolopha
Banded mongoose	115,770,000		Isotropic fractionator	Pallium (cortex)	Mungos mungo
Victoria crowned pigeon	118,445,000		Isotropic fractionator	Pallium (DVR)	Goura victoria
Yellow-knobbed curassow	124,624,000		Isotropic fractionator	Pallium (DVR)	Crax daubentoni
Indian peafowl	129,621,000		Isotropic fractionator	Pallium (DVR)	Pavo cristatus
Marbled duck	130,142,000		Isotropic fractionator	Pallium (DVR)	Marmaronetta angustirostris
Pygmy falcon	131,898,000		Isotropic fractionator	Pallium (DVR)	Polihierax semitorquatus
Common blackbird	136,000,000		Isotropic fractionator	Pallium (DVR)	Turdus merula
Wood duck	138,206,000		Isotropic fractionator	Pallium (DVR)	Aix sponsa
Red-breasted goose	148,617,000		Isotropic fractionator	Pallium (DVR)	Branta ruficollis
Budgerigar	149,000,000		Isotropic fractionator	Pallium (DVR)	Melopsittacus undulatus
Eurasian teal	167,287,000		Isotropic fractionator	Pallium (DVR)	Anas crecca
Rock hyrax	198,000,000	± 29,082,000	Isotropic fractionator	Pallium (cortex)	Procavia capensis
Northern greater galago	226,000,000	± 87,570,000	Isotropic fractionator	Pallium (cortex)	Otolemur garnettii
Common starling	226,000,000		Isotropic fractionator	Pallium (DVR)	Sturnus vulgaris
Common kestrel	237,903,000		Isotropic fractionator	Pallium (DVR)	Falco tinnunculus
Raccoon dog	240,180,000		Isotropic fractionator	Pallium (cortex)	Nyctereutes procyonoides
Common marmoset	245,000,000	± 81,180,000	Isotropic fractionator	Pallium (cortex)	Callithrix jacchus
House cat	249,830,000		Isotropic fractionator	Pallium (cortex)	Felis catus
Brown bear	250,970,000		Isotropic fractionator	Pallium (cortex)	Ursus arctos
Cockatiel	258,000,000		Isotropic fractionator	Pallium (DVR)	Nymphicus hollandicus
Greylag goose	258,650,000		Isotropic fractionator	Pallium (DVR)	Anser anser
Capybara	306,500,000	± 62,726,120	Isotropic fractionator	Pallium (cortex)	Hydrochoerus hydrochaeris
Tarsius	310,000,000		Estimated	Pallium (cortex)	Genus: Tarsius, unknown species
Mute swan	323,661,000		Isotropic fractionator	Pallium (DVR)	Cygnus olor
Greater rhea	330,342,000		Isotropic fractionator	Pallium (DVR)	Rhea americana
Eastern rosella	333,000,000		Isotropic fractionator	Pallium (DVR)	Platycercus eximius
Common buzzard	351,700,000		Isotropic fractionator	Pallium (DVR)	Buteo buteo
Red fox	355,010,000		Isotropic fractionator	Pallium (cortex)	Vulpes vulpes
Goeldi's marmoset	357,130,000		Isotropic fractionator	Pallium (cortex)	Callimico goeldii
Eurasian pygmy owl	364,000,000		Isotropic fractionator	Pallium (DVR)	Glaucidium passerinum
Western grey kangaroo	370,170,000		Isotropic fractionator	Pallium (cortex)	Macropus fuliginosus
Golden jackal	393,620,000		Isotropic fractionator	Pallium (cortex)	Canis aureus
Monk parakeet	396,000,000		Isotropic fractionator	Pallium (DVR)	Myiopsitta monachus
Springbok	396,900,000		Isotropic fractionator	Pallium (cortex)	Antidorcas marsupialis
Black vulture	398,899,000		Isotropic fractionator	Pallium (DVR)	Coragyps atratus
Azure-winged magpie	400,000,000		Isotropic fractionator	Pallium (DVR)	Cyanopica cyanus
Little owl	400,822,000		Isotropic fractionator	Pallium (DVR)	Athene noctua
Common hill myna	410,000,000		Isotropic fractionator	Pallium (DVR)	Gracula religiosa
Domesticated pig	425,000,000*		Optical fractionator	Pallium (cortex)	Sus scrofa domesticus
Barn owl	437,000,000		Isotropic fractionator	Pallium (DVR)	Tyto alba
Emu	439,000,000		Isotropic fractionator	Pallium (DVR)	Dromaius novaehollandiae
West Highland White Terrier	440,160,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris
Three-striped night monkey	442,000,000	± 111,310,000	Isotropic fractionator	Pallium (cortex)	Aotus trivirgatus
Saker falcon	442,946,000		Isotropic fractionator	Pallium (DVR)	Falco cherrug
Eurasian magpie	443,000,000		Isotropic fractionator	Pallium (DVR)	Pica pica
Raccoon	453,000,000		Isotropic fractionator	Pallium (cortex)	Procyon lotor
Chow Chow	471,500,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris
Common ostrich	479,410,000		Isotropic fractionator	Pallium (DVR)	Struthio camelus
Western jackdaw	492,000,000		Isotropic fractionator	Pallium (DVR)	Coloeus monedula
Striped hyena	495,280,000		Isotropic fractionator	Pallium (cortex)	Hyaena hyaena
Chihuahua	513,330,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris
Eurasian jay	529,000,000		Isotropic fractionator	Pallium (DVR)	Garrulus glandarius
White-tailed eagle	542,926,000		Isotropic fractionator	Pallium (DVR)	Haliaeetus albicilla
Lion	545,240,000		Isotropic fractionator	Pallium (cortex)	Panthera leo
Blesbok	570,670,000		Isotropic fractionator	Pallium (cortex)	Damaliscus pygargus phillipsi
Yorkshire Terrier	572,140,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris
Alexandrine parakeet	575,000,000		Isotropic fractionator	Pallium (DVR)	Psittacula eupatria
Tanimbar corella	599,000,000		Isotropic fractionator	Pallium (DVR)	Cacatua goffiniana
Golden retriever	627,000,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris
Gracile capuchin monkey	650,000,000^		Estimated	Pallium (cortex)	Genus: Cebus
Long-eared owl	673,000,000		Isotropic fractionator	Pallium (DVR)	Asio otus
Transylvanian Hound	725,760,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris
Greater kudu	762,570,000		Isotropic fractionator	Pallium (cortex)	Tragelaphus strepsiceros
Crab-eating macaque	800,960,000		Isotropic fractionator	Pallium (cortex)	Macaca fascicularis
Rook	820,000,000		Isotropic fractionator	Pallium (DVR)	Corvus frugilegus
Beagle	844,410,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris
Grey parrot	850,000,000		Isotropic fractionator	Pallium (DVR)	Psittacus erithacus
Komondor	883,380,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris
German Shepherd	885,460,000		Isotropic fractionator	Pallium (cortex)	Canis lupus familiaris
Sulphur-crested cockatoo	1,135,000,000		Isotropic fractionator	Pallium (DVR)	Cacatua galerita
Tufted capuchin	1,140,000,000		Isotropic fractionator	Pallium (cortex)	Sapajus apella
Tawny owl	1,153,000,000		Isotropic fractionator	Pallium (DVR)	Strix aluco
Harp seal	1,168,000,000^ 6,100,000,000*		Estimated Optical fractionator	Pallium (cortex)	Pagophilus groenlandicus
Horse	1,200,000,000*		Optical fractionator	Pallium (cortex)	Equus ferus caballus
Raven	1,204,000,000		Isotropic fractionator	Pallium (DVR)	Corvus corax
Snowy owl	1,270,000,000		Isotropic fractionator	Pallium (DVR)	Bubo scandiacus
Kea	1,281,000,000		Isotropic fractionator	Pallium (DVR)	Nestor notabilis
Eurasian eagle-owl	1,328,000,000		Isotropic fractionator	Pallium (DVR)	Bubo bubo
Common squirrel monkey	1,340,000,000	± 20,000,000	Isotropic fractionator	Pallium (cortex)	Saimiri sciureus
Bonnet macaque	1,660,000,000		Isotropic fractionator	Pallium (cortex)	Macaca radiata
Rhesus macaque	1,710,000,000		Isotropic fractionator	Pallium (cortex)	Macaca mulatta
Giraffe	1,731,000,000		Isotropic fractionator	Pallium (cortex)	Giraffa camelopardalis
Blue and yellow macaw	1,900,000,000		Isotropic fractionator	Pallium (DVR)	Ara ararauna
Pygmy sperm whale	2,020,000,000*		Optical fractionator	Pallium (cortex)	Kogia breviceps
Leopard seal	2,386,000,000^		Estimated	Pallium (cortex)	Hydrurga leptonyx
Guenon	2,500,000,000^		Estimated	Pallium (cortex)	Genus: Cercopithecus, unknown species
Pigtail Macaque	2,531,000,000^		Estimated	Pallium (cortex)	Macaca nemestrina
Gelada baboon	2,568,000,000^		Estimated	Pallium (cortex)	Theropithecus gelada
Red-and-green macaw	2,646,000,000^		Estimated	Pallium (DVR)	Ara chloropterus
Harbor porpoise	2,750,000,000*		Optical fractionator	Pallium (cortex)	Phocoena phocoena
Yellow baboon	2,880,000,000		Isotropic fractionator	Pallium (cortex)	Papio cynocephalus
Hyacinth macaw	2,944,000,000^		Estimated	Pallium (DVR)	Anodorhynchus hyacinthinus
Hamadryas baboon	2,990,000,000^		Estimated	Pallium (cortex)	Papio hamadryas
Mandrill	3,102,000,000^		Estimated	Pallium (cortex)	Mandrillus sphinx
Walrus	3,929,000,000^		Estimated	Pallium (cortex)	Odobenus rosmarus
Southern elephant seal	3,994,000,000^		Estimated	Pallium (cortex)	Mirounga leonina
African elephant	5,600,000,000		Isotropic fractionator	Pallium (cortex)	Loxodonta africana
Short-beaked common dolphin	6,700,000,000*		Optical fractionator	Pallium (cortex)	Delphinus delphis
Asian elephant	6,775,000,000^		Estimated	Pallium (cortex)	Elephas maximus
Pygmy chimpanzee or bonobo	7,250,000,000^		Estimated	Pallium (cortex)	Pan paniscus
Chimpanzee	7,400,000,000*		Optical fractionator	Pallium (cortex)	Pan troglodytes
Orangutan	7,704,000,000^ - 8,900,000,000^		Estimated	Pallium (cortex)	Genus: Pongo
Western gorilla	9,100,000,000^		Estimated	Pallium (cortex)	Gorilla gorilla
Cuvier's beaked whale	9,100,000,000*		Optical fractionator	Pallium (cortex)	Ziphius cavirostris
Beluga whale	10,000,000,000^		Estimated	Pallium (cortex)	Delphinapterus leucas
Bottlenose dolphin	12,700,000,000*		Optical fractionator	Pallium (cortex)	Tursiops truncatus
Common minke whale	12,800,000,000*		Optical fractionator	Pallium (cortex)	Balaenoptera acutorostrata
Fin whale	15,000,000,000*		Optical fractionator	Pallium (cortex)	Balaenoptera physalus
Blue whale	15,000,000,000^		Estimated	Pallium (cortex)	Balaenoptera musculus
Human	16,340,000,000 21,000,000,000*	± 2,170,000,000	Isotropic fractionator Optical fractionator	Pallium (cortex)	Homo sapiens
Risso's dolphin	18,750,000,000^		Estimated	Pallium (cortex)	Grampus griseus
Short-finned pilot whale	35,000,000,000^		Estimated	Pallium (cortex)	Globicephala macrorhynchus
Long-finned pilot whale	37,200,000,000*		Optical fractionator	Pallium (cortex)	Globicephala melas
Killer whale	43,100,000,000*		Optical fractionator	Pallium (cortex)	Orcinus orca

See also