Studies have shown that sheep are able to recognise faces of their sheep friends even after being separated for two years. elephants from strong family groups with immense memories and they cry when they are hurt (both physically and emotionally). Capuchin monkeys know when they are receiving unequal pay ( grapes vs cucumber) and Macaques develop individual cultures, particularly when it comes to how one should wash potato.
chimpanzees like to keep the peace by redistributing bananas if someone complains that their share is unfair and even rats have been shown to demonstrate empathy by giving up their favourite snack to save drowning friend. They also giggle when being tickled.
fish use tools and octopus weigh up whether effort needed to gain food reward is worth it depending on type of food. There is also plenty of evidence on how animals have individual personalities and indeed how some are a glass half full type while others are more glass half empty.