Now, when we look at the reasons why cats purr, it has many suggestions and opinions. Just as my girlfriend will explain and hold tenaciously to, the purring is simply to show when the cat is pleased with any activity around her. It might be to appreciate a favor you did to it, or to show you some love, or even to show that it is filled up after meal.
Purring is a mode of communication
For my friend, purring is a means of communication that says something to the young ones, and it shows that the cat is having some pleasurable time. But in the recent past, there have been various other notions that have disputed this seemingly correctly. These new ideas and schools of thought say that cats actually purr, mostly when they are under duress or when they are undergoing some stressful moments. This completely negates the earlier notion that they purr for joy. For these schools, it is obviously not all purring cats that are comfortable with situations. Some say that cats also purr when they pay a visit to the veterinarians, and in most cases purr to show a sign of recovery from injury. But if the latter is the case, it is also to express some sort of relief.
How cats purr
On how cats purr, many people have very different views about the methodologies of cats purring. But since this is an inner thing that takes place in the inner parts of the cat, it can only be unraveled through very rigorous and serious scientific investigations. In the past, most of the experts in the field of biology were of the opinion that cats purr were sounds that are caused by bloods that runs through the inferior vena cava of the cats. The inferior vena cava is the vein that is saddled with the function of moving blood from the lower parts of the body to the heart. So, it was believed that when this process is taking place, the purr occurs. But recently, it has been discovered that when laryngeal and diaphragmatic muscles of the cat are signaled intermittently, the purring occurs. It is during this process of inhaling and exhaling that the actual purring occurs, and this has a consistent frequency of about 25 and 150 Hertz. The discovery is that when this sounds occur, they have the health advantages of promoting healing for the body, and increase in the solidity of the bones. So, the purring is obviously very healthy for the cat.
It is also good to note that it is not all cats that purr. In the past, it was held that only the domestic cats purr, but it was later discovered that many other species and types of cats also purr.