Lions use a variety of facial expressions to convey different emotions. For example, when a lion is feeling aggressive, it may bare its teeth, flatten its ears, and narrow its eyes. When feeling submissive, a lion may lower its head, flatten its body, and avoid eye contact. To show affection, lions may rub heads, groom each other, or even purr. These facial expressions help lions communicate with each other and establish social hierarchies within their pride.