New research shows that unlike dogs, cats do not see their human owners as a source of protection or security.

In recent years cats have been shown to be more capable of shared relationships than previously believed, but animal behavioral specialists have determined they do not rely on others to feel safe, the University of Lincoln reported.

"The domestic cat has recently passed the dog as the most popular companion animal in Europe, with many seeing a cat as an ideal pet for owners who work long hours. Previous research has suggested that some cats show signs of separation anxiety when left alone by their owners, in the same way that dogs do, but the results of our study show that they are in fact much more independent than canine companions. It seems that what we interpret as separation anxiety might actually be signs of frustration," said  Daniel Mills, professor of veterinary behavioral medicine at the University of Lincoln's School of Life Sciences.

To make their findings, the researchers adapted the Ainsworth Strange Situation Test (SST), which has been used in the past to evaluate the bond between young women or dogs and their primary caregivers. The cats were placed in unfamiliar environments with their owners, a stranger and on their own. During each of these scenarios, three different characteristics of attachment were assessed: "the amount of contact sought by the cat, the level of passive [behavior], and signs of distress caused by the absence of the owner."

The findings revealed cats were more vocal when their owners were present, but there were no signs that they had a sense of secure attachment in regard to their owners. The researchers believe the vocalization may be either a signal of frustration or a learned behavior. When in strange situations, attached individuals generally stay close to their caregivers for protection. In these predicaments attached individuals also show signs of distress when their caregiver is removed from the situation and pleasure when they return; none of these behaviors were observed in cats. 

"For pet dogs, their owners often represent a specific safe haven; however it is clear that domestic cats are much more autonomous when it comes to coping with unusual situations. Our findings don't disagree with the notion that cats develop social preferences or close relationships, but they do show that these relationships do not appear to be typically based on a need for safety and security. As far as we could tell, the cats of owners who considered them to be highly attached did not differ from the others in this regard," Mills concluded.

The findings were published in a recent edition of the journal PLOS One.