Cat intelligence is the capacity of the domesticated cat to solve problems and adapt to its environment. Researchers have shown feline intelligence to include the ability to acquire new behavior that applies knowledge to new situations, communicating needs and desires within a social group and responding to training cues.
The brain of the domesticated cat is about five centimetres (2.0 in) long and weighs 25–30 g (0.88–1.06 oz). If a typical cat is taken to be 60 cm (24 in) long with a weight of 3.3 kg (7.3 lb), then the brain would be at 0.91% of its total body mass, compared to 2.33% of total body mass in the average human. Within the encephalization quotient proposed by Jerison in 1973, values above one are classified big-brained, while values lower than one are small-brained. The domestic cat is attributed a value of between 1–1.71; relative to human value, that is 7.44–7.8.
The largest brains in the family Felidae are those of the tigers in Java and Bali. It is debated whether there exists a causal relationship between brain size and intelligence in vertebrates. Correlations have been shown between these factors in a number of experiments; however, correlation does not imply causation. Most experiments involving the relevance of brain size to intelligence hinge on the assumption that complex behavior requires a complex (and therefore intelligent) brain; however, this connection has not been consistently demonstrated.
The surface area of a cat's cerebral cortex is approximately 83 cm2 (13 in2); furthermore, a theoretical cat weighing 2.5 kg (5.5 lb) has a cerebellum weighing 5.3 g (0.19 oz), 0.17% of the total weight.
According to researchers at Tufts University School of Veterinary Medicine, the physical structure of the brains of humans and cats is very similar. The human brain and the cat brain both have cerebral cortices with similar lobes.
The number of cortical neurons contained in the brain of the cat is reported to be 203 million. Area 17 of the visual cortex was found to contain about 51,400 neurons per mm3. Area 17 is the primary visual cortex.
Analyses of cat brains have shown they are divided into many areas with specialized tasks that are vastly interconnected and share sensory information in a kind of hub-and-spoke network, with a large number of specialized hubs and many alternative paths between them. This exchange of sensory information allows the brain to construct a complex perception of the real world and to react to and manipulate its environment.
Secondary brain structures
The domestic cat brain also contains the hippocampus, amygdala, frontal lobes (which comprise 3 to 3.5% of the total brain in cats, compared to about 25% in humans), corpus callosum, anterior commissure, pineal gland, caudate nucleus, septal nuclei and midbrain.
Grouse et al. (1979) ascertained the neuroplasticity of kittens' brains, with respect to control of visual stimulus correlated with changes in RNA structures. In a later study, it was found that cats possess visual-recognition memory, and have flexibility of cerebral encoding from visual information.
Brain and diet
A cognitive support diet for felines is a food that is formulated in order to improve mental processes like attention, short and long-term memory, learning, and problem solving. Claims for cognitive support appear on a number of kitten formulations to help with brain development, as well as diets aimed at seniors to help prevent cognitive disorders. These diets typically focus on supplying Omega-3 fatty acids, omega-6 fatty acids, taurine, vitamins, and other supporting supplements that have positive effects on cognition.
The omega-3 fatty acids are a key nutrient in cognition for felines. They are essential for felines as they cannot be synthesized naturally and must be obtained from the diet. Omega-3 fatty acids that support brain development and function are alpha-linolenic acid, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Fish oils, fish and other marine sources provide a very rich source of DHA and EPA. Alpha-linolenic acid can be acquired from oils and seeds.
Omega-6 fatty acids are also needed in feline cognition diets. The important omega-6 fatty acid that plays a role in brain support and cognition is arachidonic acid. Arachidonic acid, or AA, is found in animal sources such as meat and eggs. AA is required in cat diets, as felines convert insignificant amounts of it from linoleic acid due to the limited enzyme delta-6 desaturase. Like DHA, arachidonic acid is often found in the brain tissues of cats and seems to have a supporting role in brain function. In a 2000 study completed by Contreras et al., it was found that DHA and AA made up 20% of the fatty acids in the mammalian brain. Arachidonic acid makes up high amounts in the membrane of most cells and has many pro-inflammatory actions.
Taurine is an amino acid, which is essential in cat diets due to their low capacity to synthesize it. Taurine has the ability to cross the blood–brain barrier in the brain, it plays a role in many neurological functions, especially in the visual development. Without taurine, felines can have an abnormal morphology in the cerebellum and visual cortex. When cats were fed a diet deficient in taurine, this led to a decrease in the concentration of taurine in the retina of the eye. This resulted in deterioration of the photoreceptors, followed by complete blindness.
Choline is a water-soluble nutrient that prevents and improves epilepsy and cognitive disorders. Supplementation is part of therapy for cats with seizures and feline cognitive dysfunction, despite this treatment being mostly based on anecdotal evidence and research done on dogs. It is the precursor to nerve chemicals like dopamine and acetylcholine, making it important for proper functioning of the nervous system.
Intelligence through behavioural observation is defined as a composite of skills and abilities.
The WAIS test is a measure of intelligence in adult Homo sapiens. The test scores on four criteria: verbal comprehension, perceptual organization, working memory and processing speed.Cite error: Closing
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In 2009, an experiment was conducted where cats could pull on a string to retrieve a treat under a plastic screen. When presented with one string, cats had no trouble getting the treats, but when presented with multiple strings, some of which were not connected to treats, the cats were unable to consistently choose the correct strings, leading to the conclusion that cats do not understand cause and effect in the same way that humans do.
Cats have complex dreams while sleeping, retaining and recalling long sequences of events while they are asleep, as many other animals do. A dreaming cat will sometimes have rapid, uncontrolled facial, whisker, paw, and abdominal movements.
Taken as a whole, cats have excellent memories. In experimental conditions, the memory of a cat was demonstrated as having an information-retention or recall of a duration totaling as much as 10 years. In wild cats, such as lions, selective pressures have demonstrated that these animals exhibit extensive long-term memory in relation to problem-solving for at least seven months after solution. However, relationships with humans, individual differences in intelligence, and age may all affect memory. Cats easily adapt to their current environment because they can adapt their memories of past environments throughout their lives.
The period during which the cat is a kitten is the time when the cat learns and memorizes survival skills, which are acquired through observation of their mothers and playing with other cats. Playing, in fact, constitutes more than fun for a kitten, for it is essential for ranking social order, building hunting skills, and for generally exercising for the adult roles.
The first two to seven weeks are a particularly critical time for kittens, for it is during this period that they bond with other cats. It has been suspected that without any human contact during this time, the cat would forever mistrust humans, or would at least take many times longer than with such early exposure before the mistrust might begin to erode. They also may not extend trust developed with a select group of familiar nonthreatening humans as readily to strangers. Many cats with exposure during this period as kittens still do not automatically trust strangers.
In older cats
Just as in humans, advancing age may affect memory in cats. Some cats may experience a weakening of both learning ability and memory that affects them adversely in ways similar to those occurring in poorly aging humans. A slowing of function is normal, and this includes memory. Aging may affect memory by changing the way their brain stores information and by making it harder to recall stored information. Cats lose brain cells as they age, just as humans do.
The older the cat, the more these changes can affect its memory. There have been no studies done on the memories of aging cats, but there is some speculation that, just like people, short-term memory is more affected by aging. In one test of where to find food, cats' short-term memory lasted about 16 hours.
Diseases, such as feline cognitive dysfunction (FCD) – a condition similar to Alzheimer's disease in humans – could also affect cat memory. Symptoms of FCD include disorientation, reduced social interaction, sleep disturbances, and loss of house training. FCD causes degenerative changes in the brain that are the source of the functional impairment.
Edward Thorndike conducted some key experiments on cats' learning capacity. In one of Thorndike's experiments, cats were placed in various boxes approximately 20 in × 15 in × 12 in (51 cm × 38 cm × 30 cm) with a door opened by pulling a weight attached to it. The cats were observed to free themselves from the boxes by "trial and error with accidental success." Though cats did perform worse on occasion, Thorndike generally found that as cats continued the trials, the time taken to escape the boxes decreased in most cases.
Thorndike considered the cat to follow the law of effect, which states that responses followed by satisfaction (i.e. a reward) become more likely responses to the same stimulus in the future. Thorndike was generally skeptical of the presence of intelligence in cats, criticising sources of the contemporary writing of the sentience of animals as "partiality in deductions from facts and more especially in the choice of facts for investigation."
An experiment was done to identify possible observational learning in kittens. Kittens that were able to observe their mothers performing an experimentally organised act were able to perform the same act sooner than kittens that had observed a non-related adult cat, and sooner than the ones who, being placed in trial and error conditions, observed no other cat performing the act.
Cat intelligence study is mostly from consideration of the domesticated cat. The process of domestication has allowed for closer observation of cat behaviour and in the increased incidence of interspecies communication, and the inherent plasticity of the cat's brain has become apparent as the number of studies in this have increased scientific insight.
Changes in the genetic structure of a number of cats have been identified. This is as a consequence of both domestication practises and the activity of breeding, so that the species has undergone genetic evolutionary change due to human selection. This human selection has been coupled with an initial, naturally occurring selective set of cats, possessing characteristics desirable for the sharing of human habitation and living in Neolithic urban environments.
Cats' intelligence may have increased during their semi-domestication: urban living may have provided an enriched and stimulating environment requiring novel adaptive behaviours. This scavenging behaviour would only have produced slow changes in evolutionary terms, but such changes would have been comparable to the changes to the brain of early primitive hominids who co-existed with primitive cats (like, for example, Machairodontinae, Megantereon and Homotherium) and adapted to savannah conditions.
However, urban living is unlikely to improve the animal's intelligence indefinitely. The cat, both feral and domesticated, is likely to be maintained in an evolutionary stasis by its niche position in the food web.
- Animal intelligence
- "Animals have complex dreams, MIT researcher proves". https://news.mit.edu/2001/dreaming.
- Louie, K; Wilson, MA (January 2001). "Temporally structured replay of awake hippocampal ensemble activity during rapid eye movement sleep". Neuron 29 (1): 145–156. doi:10.1016/s0896-6273(01)00186-6. PMID 11182087.
- Roth, Gerhard; Dicke, Ursula (2005). "Evolution of the brain and intelligence". Trends in Cognitive Sciences 9 (5): 250–7. doi:10.1016/j.tics.2005.03.005. PMID 15866152.
- Kinser, Patricia Anne. "Brain and Body Size". Serendip. Bryn Mawr College. http://serendip.brynmawr.edu/bb/kinser/Size1.html.
- Freberg, Laura (2009). "Relative Encephalization Quotients". Discovering Biological Psychology. p. 56. ISBN 978-0-547-17779-3. https://books.google.com/books?id=-zyTMXAjzQsC&pg=PA56.
- Davies, Paul (2010). "How Much Intelligence is Out There?". The Eerie Silence: Renewing Our Search for Alien Intelligence. pp. 66–92. ISBN 978-0-547-48849-3. https://books.google.com/books?id=gscYcI4uHhkC&pg=PA66.
- Yamaguchi, Nobuyuki; Kitchener, Andrew C.; Gilissen, Emmanuel; MacDonald, David W. (2009). "Brain size of the lion (Panthera leo) and the tiger (P. Tigris): Implications for intrageneric phylogeny, intraspecific differences and the effects of captivity". Biological Journal of the Linnean Society 98 (1): 85–93. doi:10.1111/j.1095-8312.2009.01249.x.
- Healy, Susan D.; Rowe, Candy (2007). "A critique of comparative studies of brain size". Proceedings of the Royal Society B: Biological Sciences 274 (1609): 453–64. doi:10.1098/rspb.2006.3748. PMID 17476764.
- Outhwaite, William (2006). The Blackwell dictionary of modern social thought (2nd ed.). Wiley-Blackwell. p. 257. ISBN 978-1-4051-3456-9.
- Weiner, Irving B.; Craighead, W. Edward (2010). The Corsini Encyclopedia of Psychology. 4. John Wiley & Sons. p. 1857.
- Sorabji, Richard (1995). Animal Minds and Human Morals: The Origins of the Western Debate. Cornell University Press. ISBN 978-0-8014-8298-4.
- Allen, Colin (13 October 2010). "Animal Consciousness". in Zalta, Edward N.. The Stanford Encyclopedia of Philosophy. http://plato.stanford.edu/archives/win2011/entries/consciousness-animal/.
- Nieuwenhuyis, Rudolf; ten Donkelaar, Hendrik Jan; Nicholson, Charles (1998). The Central Nervous System of Vertebrates. ISBN 978-3-540-56013-5.
- Gross, Richard (2010). Psychology: The Science of Mind and Behaviour. ISBN 978-1-4441-0831-6.
- Mann, M (1979). "Sets of neurons in somatic cerebral cortex of the cat and their ontogeny". Brain Research Reviews 180 (1): 3–45. doi:10.1016/0165-0173(79)90015-8. PMID 385112.
- "How Smart Is Your Cat?". Cat Watach. Cornell University College of Veterinary Medicine. February 2010. http://www.catwatchnewsletter.com/issues/14_2/features/140970-1.html.
- 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.
- Kosslyn, S. M.; Pascual-Leone, A; Felician, O; Camposano, S; Keenan, JP; Thompson, WL; Ganis, G; Sukel, KE et al. (1999). "The Role of Area 17 in Visual Imagery: Convergent Evidence from PET and rTMS". Science 284 (5411): 167–70. doi:10.1126/science.284.5411.167. PMID 10102821. Bibcode: 1999Sci...284..167K.
- Solnick, Bennett; Davis, Thomas L.; Sterling, Peter (1984). "Numbers of Specific Types of Neuron in Layer IVab of Cat Striate Cortex". Proceedings of the National Academy of Sciences of the United States of America 81 (12): 3898–900. doi:10.1073/pnas.81.12.3898. PMID 6587398. Bibcode: 1984PNAS...81.3898S.
- Beaulieu, Clermont; Colonnier, Marc (1989). "Number of neurons in individual laminae of areas 3B, 4?, and 6a? Of the cat cerebral cortex: A comparison with major visual areas". The Journal of Comparative Neurology 279 (2): 228–34. doi:10.1002/cne.902790206. PMID 2913067.
- "visual cortex". Farlex. http://medical-dictionary.thefreedictionary.com/area+17+of+Brodmann.
- "Gyrencephalic Definition". Serendip. http://serendip.brynmawr.edu/bb/kinser/definitions/def-gyre.html.
- Smith, J. M.; James, M. F.; Bockhorst, K. H. J.; Smith, M. I.; Bradley, D. P.; Papadakis, N. G.; Carpenter, T. A.; Parsons, A. A. et al. (2001). "Investigation of feline brain anatomy for the detection of cortical spreading depression with magnetic resonance imaging". Journal of Anatomy 198 (5): 537–54. doi:10.1017/S002187820100766X. PMID 11430693.
- Kurths, Jürgen; Zhou, Changsong; Zamora-López, Gorka (2011). "Exploring Brain Function from Anatomical Connectivity". Frontiers in Neuroscience 5: 83. doi:10.3389/fnins.2011.00083. PMID 21734863.
- Feig, Sherry; Harting, John K. (1998). "Corticocortical communication via the thalamus: Ultrastructural studies of corticothalamic projections from area 17 to the lateral posterior nucleus of the cat and inferior pulvinar nucleus of the owl monkey". The Journal of Comparative Neurology 395 (3): 281–95. doi:10.1002/(SICI)1096-9861(19980808)395:3<281::AID-CNE2>3.0.CO;2-Z. PMID 9596524.
- Huang, Chuong C; Lindsley, Donald B (1973). "Polysensory responses and sensory interaction in pulvinar and related postero-lateral thalamic nuclei in cat". Electroencephalography and Clinical Neurophysiology 34 (3): 265–80. doi:10.1016/0013-4694(73)90254-X. PMID 4129614.
- Bear, Mark F.; Connors, Barry W.; Paradiso, Michael A. (2007). "Neural Components of Aggression Beyond the Amygdala". Neuroscience: Exploring the Brain. pp. 579–81. ISBN 978-0-7817-6003-4. https://books.google.com/books?id=DbahEn-y6AoC&pg=PA579.
- Fourment, A.; Hirsch, J.C. (1980). "Synaptic potentials in cat's lateral geniculate neurons during natural sleep with special reference to paradoxical sleep". Neuroscience Letters 16 (2): 149–54. doi:10.1016/0304-3940(80)90335-3. PMID 6302571.
- Adamec, R.E.; Stark-Adamec, C. (1983). "Partial kindling and emotional bias in the cat: Lasting aftereffects of partial kindling of the ventral hippocampus". Behavioral and Neural Biology 38 (2): 205–22. doi:10.1016/S0163-1047(83)90212-1. PMID 6314985.
- Marcos, P; Coveñas, R; Narvaez, J.A; Aguirre, J.A; Tramu, G; Gonzalez–Baron, S (1998). "Neuropeptides in the Cat Amygdala". Brain Research Bulletin 45 (3): 261–8. doi:10.1016/S0361-9230(97)00343-2. PMID 9580215.
- Forrest, David V. (2002). "The Executive Brain: Frontal Lobes and the Civilized Mind". American Journal of Psychiatry 159 (9): 1615–6. doi:10.1176/appi.ajp.159.9.1615.
- Diamond, Adele (2011). "Frontal Lobe Involvement in Cognitive Changes During the First Year of Life". in Gibson, Kathleen R.; Petersen, Anne C.. Brain Maturation and Cognitive Development: Comparative and Cross-Cultural Perspectives. pp. 127–80. ISBN 978-1-4128-4450-5. https://books.google.com/books?id=FkOBOcj7a0kC&pg=PA127.
- Clarke, Stephanie; de Ribaupierre, François; Bajo, Victoria M.; Rouiller, Eric M.; Kraftsik, Rudolf (1995). "The auditory pathway in cat corpus callosum". Experimental Brain Research 104 (3): 534–40. doi:10.1007/BF00231988. PMID 7589305.
- Payne, B. R.; Siwek, D. F. (1991). "The Visual Map in the Corpus Callosum of the Cat". Cerebral Cortex 1 (2): 173–88. doi:10.1093/cercor/1.2.173. PMID 1822731.
- Ebner, Ford F.; Myers, Ronald E. (1965). "Distribution of corpus callosum and anterior commissure in cat and raccoon". The Journal of Comparative Neurology 124 (3): 353–65. doi:10.1002/cne.901240306. PMID 5861718.
- Boya, Jesús; Calvo, Jose Luis; Rancano, Dolores (1995). "Structure of the pineal gland in the adult cat". Journal of Pineal Research 18 (2): 112–8. doi:10.1111/j.1600-079X.1995.tb00148.x. PMID 7629690.
- Peters, D. A. V.; McGeer, P. L.; McGeer, E. G. (1968). "The Distribution of Tryptophan Hydroxylase in Cat Brain". Journal of Neurochemistry 15 (12): 1431–5. doi:10.1111/j.1471-4159.1968.tb05924.x. PMID 5305846.
- Grouse, Lawrence D.; Schrier, Bruce K.; Nelson, Phillip G. (1979). "Effect of visual experience on gene expression during the development of stimulus specificity in cat brain". Experimental Neurology 64 (2): 354–64. doi:10.1016/0014-4886(79)90275-9. PMID 428511.
- Okujav, Vazha; Natishvili, Teimuraz; Gogeshvili, Ketevan; Gurashvili, Thea; Chipashvili, Senera; Bagashvili, Tamila; Andronikashvili, George; Okujava, Natela (2009). "Visual Recognition Memory in Cats: Effects of Massed vs. Distributed Trials". Bulletin of the Georgian National Academy of Sciences 3 (2): 168–72. http://www.science.org.ge/moambe/3-2/Okujava.pdf.
- Okujava, Vazha; Natishvili, Teimuraz; Mishkin, Mortime; Gurashvili, Thea; Chipashvili, Senera; Bagashvili, Tamil; Andronikashvili, George; Kvernadze, George (2005). "One-trial visual recognition in cats". Acta Neurobiologiae Experimentalis 65 (2): 205–11. PMID 15960308. http://www.ane.pl/linkout.php?vol=65&no=2&fpp=205.
- Fiset, Sylvain; Doré, François Y. (1996). "Spatial encoding in domestic cats (Felis catus)". Journal of Experimental Psychology: Animal Behavior Processes 22 (4): 420–37. doi:10.1037/0097-7403.22.4.420. PMID 8865610.
- Covington, MB. (2004). "Omega-3 Fatty Acids". American Family Physician 70 (1): 133–140. PMID 15259529. http://www.aafp.org/afp/2004/0701/p133.html#.
- Bauer EB. (2006). "Metabolic basis for the essential nature of fatty acids and the unique dietary fatty acid requirement of cats.". Journal of the American Veterinary Medical Association 229 (11): 1729–32. doi:10.2460/javma.229.11.1729. PMID 17144816.
- "The role of dietary omega-3 and omega-6 essential fatty acids in the nutrition of dogs and cat: A review.". Progress in Nutrition 6 (2): 1–13. 2004.
- "Nutritional deprivation of alpha-linolenic acid decreases but does not abolish turnover and availability of unacylated docosahexaenoic acid and docosahexaenoyl-CoA in rat brain.". Journal of Neurochemistry 75 (6): 2392–400. 2000. doi:10.1046/j.1471-4159.2000.0752392.x. PMID 11080190.
- "Feline maternal taurine deficiency: Effects on visual cortex of the offspring. A morphometric and immunohistochemical study". Taurine in Health & Disease. Advances in Experimental Medicine and Biology. 359. 1994. pp. 369–84. doi:10.1007/978-1-4899-1471-2_38. ISBN 978-1-4899-1473-6.
- "Taurine in development.". Life Sciences 21 (1): 1–21. 1977. doi:10.1016/0024-3205(77)90420-9. PMID 329037.
- Shawn., Messonnier (2012). Nutritional supplements for the veterinary practice : a pocket guide. American Animal Hospital Association.. Lakewood, Colo.: AAHA Press. ISBN 9781583261743. OCLC 794670587.
- Shawn., Messonnier (2001). Natural health bible for dogs & cats : your A-Z guide to over 200 conditions, herbs, vitamins, and supplements (1st ed.). Roseville, Calif.: Prima. ISBN 9780761526735. OCLC 45320627.
- Heishman, M.; Conant, M.; Pasnak, R. (June 1995). "Human Analog Tests of the Sixth Stage of Object Permanence". Percept mot Skills 80 (3): 1059–1068. doi:10.2466/pms.1995.80.3c.1059. PMID 7478858. http://pms.sagepub.com/content/80/3_suppl/1059.refs.
- B. Osthaus Meikle, James (16 June 2009). "Cats outsmarted in psychologist's test". The Guardian. https://www.theguardian.com/science/2009/jun/16/psychologist-test-outsmarts-cats.
- Pallaud, B. (1984). "Hypotheses on mechanisms underlying observational learning in animals". Behavioural Processes 9 (4): 381–394. doi:10.1016/0376-6357(84)90024-X. PMID 24924084.
- "Feline Intelligence". 2013-01-23. http://www.animalplanet.com/pets/cat-intelligence/. "Once attained, even if by accident or trial and error, most knowledge is retained for life, thanks to the cat's excellent memory."
- Borrego, Natalia (2017-08-01). "Big cats as a model system for the study of the evolution of intelligence" (in en). Behavioural Processes. Feline Behavior & Cognition 141 (Pt 3): 261–266. doi:10.1016/j.beproc.2017.03.010. ISSN 0376-6357. PMID 28336301. https://www.sciencedirect.com/science/article/pii/S0376635716302960.
- Stock, Judith A. Pet Place. 1 January 2011. Web. 24 March 2011.
- Pawprints and Purrs. Cat Health. 11 October 2010. Web. 24 March 2011.
- Little, Susan (2011-10-14) (in en). The Cat: Clinical Medicine and Management. Elsevier Health Sciences. ISBN 978-1-4377-0661-1. https://books.google.com/books?id=rnyakraHGdcC&dq=kitten+play+development&pg=PA185.
- Memory Loss With Aging. Family Doctor. 22 January 1996. Web. 24 March 2011.
- "Do Cats Have Long-Term Memory?". http://pets.thenest.com/cats-longterm-memory-8646.html. "As Kitty ages, his brain function will decline. Feline cognitive dysfunction is a disease similar to Alzheimer's in humans. It is caused by deterioration of the brain itself, leading to reduced cognitive functioning. A cat with this condition has trouble getting around, because he becomes disoriented easily."
- Thorndike, Edward Lee (1911). Animal Intelligence. Macmillan Company. p. 150. https://archive.org/details/animalintellige00thorgoog.
- D.Bernstein; L. A. Penner; A. Clarke-Stewart; E. J. Roy (October 2007). Psychology. Cengage Learning. p. 205. ISBN 978-0-618-87407-1. https://books.google.com/books?id=dHd7tacWS7oC&pg=PA205. Retrieved 24 December 2011.
- Thorndike, Edward Lee (1898). Animal Intelligence. pp. 38–42. ISBN 9780722230831. https://books.google.com/books?id=jfJGAAAAYAAJ.
- Budiansky, Stephen (1911). If a Lion Could Talk: Animal Intelligence and the Evolution of Consciousness. ISBN 978-0-684-83710-9. https://books.google.com/books?id=Go8XozILUJYC&pg=PA23. Retrieved 16 April 2012.
- Chesler, P. (1969). "Maternal Influence in Learning by Observation in Kittens". Science 166 (390): 901–903. doi:10.1126/science.166.3907.901. PMID 5345208. Bibcode: 1969Sci...166..901C.
- Case, Linda P. (2003). The cat: its behavior, nutrition, & health. Wiley-Blackwell. ISBN 978-0-8138-0331-9. https://books.google.com/books?id=mdg0R6nDWgoC&pg=PA123.
- Turner, D. C. (2000). The domestic cat: the biology of its behaviour. Cambridge University Press. ISBN 978-0-521-63648-3. https://books.google.com/books?id=zBYi4NgVwCUC&pg=PR7.
- Boone 1956
- Fox 1980
- Driscoll, C. A.; Menotti-Raymond, M.; Roca, A. L.; Hupe, K.; Johnson, W. E.; Geffen, E.; Harley, E. H.; Delibes, M. et al. (2007). "The Near Eastern Origin of Cat Domestication". Science 317 (5837): 519–23. doi:10.1126/science.1139518. PMID 17600185. Bibcode: 2007Sci...317..519D.
- "Evolution of the cat". The Feline Advisory Bureau. http://www.fabcats.org/behaviour/understanding/evolution.html.
- Driscoll, Carlos A.; MacDonald, David W.; O'Brien, Stephen J. (2009). "Colloquium Papers: From wild animals to domestic pets, an evolutionary view of domestication". Proceedings of the National Academy of Sciences 106 (Suppl 1): 9971–8. doi:10.1073/pnas.0901586106. PMID 19528637. Bibcode: 2009PNAS..106.9971D.
- Carlstead, Kathy; Brown, Janine L.; Seidensticker, John (1993). "Behavioral and adrenocortical responses to environmental changes in leopard cats (Felis bengalensis)". Zoo Biology 12 (4): 321–31. doi:10.1002/zoo.1430120403.
- "Rare scavenging wild cat – Jaguar". Stalking the Jaguar. BBCWorldwide. https://www.youtube.com/watch?v=I-PIjQRYQZ0.
- Stanford, Craig B.; Bunn, Henry T., eds (2001). Meat-Eating and Human Evolution. ISBN 978-0-19-535129-3.
- Linseele, Veerle; Van Neer, Wim; Hendrickx, Stan (2007). "Evidence for early cat taming in Egypt". Journal of Archaeological Science 34 (12): 2081–90. doi:10.1016/j.jas.2007.02.019.
- Tobias, Philip V. (1992). "Paleoecology of Hominid Emergence". in Schopf, J. William. Major Events in the History of Life. pp. 147–58. ISBN 978-0-86720-268-7. https://books.google.com/books?id=py01HMuAIh4C&pg=PA147.
- Croitor, Roman (17 March 2010). "On supposed ecological relationship of the early representatives of the genus Homo and saber-toothed cats". SciTopics. http://www.scitopics.com/On_supposed_ecological_relationship_of_the_early_representatives_of_the_genus_Homo_and_saber_toothed_cats.html.
- Hart, Donna; Sussman, Robert W. (2011). "The Influence of Predation on Primate and Early Human Evolution: Impetus for Cooperation". in Sussman, Robert W.; Cloninger, C. Robert. Origins of Altruism and Cooperation. pp. 19–40. doi:10.1007/978-1-4419-9520-9_3. ISBN 978-1-4419-9519-3. https://books.google.com/books?id=bMEC1AAKsP8C&pg=PA19.
- Jordán, Ferenc; Liu, Wei-Chung; Davis, Andrew J. (2006). "Topological keystone species: Measures of positional importance in food webs". Oikos 112 (3): 535–46. doi:10.1111/j.0030-1299.2006.13724.x.
- Bergler, Reinhold "Man and Cat: The Benefits of Cat Ownership" Blackwell Scientific Publications (1989)
- Bradshaw, John W S "The Behaviour of the Domestic Cat" C A B International (1992)
- Chesler, P. (1969). "Maternal Influence in Learning by Observation in Kittens". Science 166 (3907): 901–3. doi:10.1126/science.166.3907.901. PMID 5345208. Bibcode: 1969Sci...166..901C.
- Hobhouse, L T Mind in Evolution MacMillan, London (1915)
- Turner, Dennis C, and Patrick Bateson. "The Domestic Cat: The Biology of Its Behaviour" Cambridge University Press (1988)
- Miles, R. C. (1958). "Learning in kittens with manipulatory, exploratory, and food incentives". Journal of Comparative and Physiological Psychology 51 (1): 39–42. doi:10.1037/h0049255. PMID 13513843.
- Neville, Peter "Claws and Purrs" Sidgwick & Jackson (1992)
- Neville, Peter "Do Cats Need Shrinks" Sidgwick & Jackson (1990)
- Voith, VL (1981). "You, too, can teach a cat tricks (examples of shaping, second-order reinforcement, and constraints on learning)". Modern Veterinary Practice 62 (8): 639–42. PMID 7290076.
- D.M.Fankhauser biology.clc.uc.edu Removal and study of the cat brain and Cranial nerves of the cat biology.clc.uc.edu [Retrieved 2011-12-22] (images and instruction) for an anatomy and physiology class for the dissecting of the brain of a cat
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