The brain of the domesticated cat is about five centimetres (2.0 in) long, and weighs 25–30 g (0.88–1.06 oz).[1][2] 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%[3] of its total body mass, compared to 2.33%[3] of total body mass in the average human. Within the encephalization quotient proposed by Jerison in 1973,[3][4] values above 1 are classified big brained, while values lower than 1 are small brained.[5] The domestic cat is attributed a value of between 1–1.71 relative to human value that is 7.44–7.8.[1][3] The largest brains in the Felidae family are those of the tigers in Java and Bali, of which the largest relative brain size within the panthera is the tigris.[6] 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.