Dogs are prone to complex emotions such as jealousy and pride, according to scientific research that sheds new light on their relationship with humans.

Dogs feel intense jealously when they spot that they are unfairly treated.

Canines do not like seeing their owners offering affection to other creatures, especially other dogs, and react negatively when their owners bring home new partners, the research found.

Psychologists previously believed most animals lack the "sense of self" needed to experience so-called secondary emotions such as jealousy, embarrassment, empathy or guilt. These emotions are more complex than feelings associated with instant reaction – such as anger, lust or joy.

Dr Friederike Range, of the University of Vienna's neurobiology department, has shown that dogs feel intense jealously when they spot that they are unfairly treated compared with other dogs. "Dogs show a strong aversion to inequity," she said.

The dog study is the latest into several species, including cows, horses, cats and sheep, which have shown that animals are far more self-aware than was thought.

Dr Paul Morris, a psychologist at the University of Portsmouth who studies animal emotions, told The Sunday Times: "We are learning that dogs, horses, and perhaps many other species are far more emotionally complex than we ever realised. They can suffer simple forms of many emotions we once thought only primates could experience."

In research among dog owners, Dr Morris found almost all of them reported jealous behaviour by their pets. The dog often tried to prise their owner away from a new lover in the early days of a relationship.

Behavioural experts recommend owners keeping their dog's routine as much as possible when a new partner or child comes along in order to prevent jealous activity from the dog such as interruptions with barking or whining.

根据科学研究，狗同人类的关系又有了新的认识，狗也可能有复杂情感，诸如嫉妒和骄傲等。

当狗认为遭遇不公平对待时，它们会表现出强烈的妒忌。

研究发现，犬齿不喜欢看到他们的主人对别的动物尤其是别的狗表示友好，当主人带回新的宠物，它们则反应消极。

心理学家以前曾认为，大多数动物缺乏体验所谓的高级情感需求的“自我意识”，比如妒忌、困窘、同理心或内疚。这些情感比即时反应所关联的情感——例如愤怒、渴望或快乐更为复杂。

维也纳大学神经生物学系Friederike Range博士给人演示了，狗认为同其他狗相比受到不公平待遇会表现出激烈的妒忌情绪。她说，“面对不公正狗会表示强烈的厌恶。”

关于狗的研究是最近才介入的，几类物种包括牛、马、猫和羊的研究已表明，动物具有自我意识，远远超过我们的想象。

研究动物情感的朴茨茅斯大学心理学家Paul Morris博士告诉《星期日泰晤士报》：“我们知道，狗、马、或许很多其他物种的情感都远远比我们觉察到的更为复杂。他们能够忍受简单形式的许多情感，而那些情感，我们曾以为只有灵长目动物才会经历。”

在对狗主人的研究中，Morris博士发现,几乎所有人都反映他们的宠物有嫉妒行为。在一段关系开始初期，狗经常想从主人新宠那里夺回主人（的关爱）。

行为学专家建议狗主们，当一个新伴侣或小孩来到生活中时，为了不让妒忌行为发生在狗身上，避免因狗吠或其哀号被打扰，主人应尽可能多地与狗保持以往的关系。