Greetings Juantoo Just wanted to provide you with a further link on intelligence in birds. This one primarily deals with crows. I would agree there does appear to be a cut off point in animals equivilant to about an average 4yr old human. I noted in both my own children that about that age there is a change in them, and its about that age the human brain at last stops growing and is fully formed. For my eldest son this change was striking especialy in terms of memory. At age four he would describe with much detail memories of the house we lived in for only the first 6 months of his life. Infact his recal was perfect for everything that happened to him up till about that age. A year later 95% of it was forgotten. Quite a strange phenomenon. Perhaps once we know more about intelligence in the animal kingdom we will begin to be able to make correlations that are qualifiable. The Human animal is undoubtedly diffierent and in evolutionary terms this change was very recent so its a logical step to say that what makes us conciously human starts when our brains are fully grown. Though I offer no evidence to support it other than my knowledge of brain development in humans and a hunch. Anyway heres the link I promised; http://www.pbs.org/lifeofbirds/brain/ peace Edit afterthought; It was about age 5 that my eldest son first talked in terms of religeons. I had always taken him in to a nearby cathedral as an infant and explained to him in simplistic terms what it was for. But at 5 he said to me 'I am glad people believe in Jesus'. When I asked why his reply was 'It means I get nice Christmas presents'