Within our list, humans take the top spot, and animals they have domesticated the remaining nine. Per current estimates, four species of mammals currently have global populations in excess of 1 billion members. Feeding and housing such large populations of humans and animals alike in coming years will likely require efficient resource management and all the ingenuity we can muster.
10. Donkey (40 million)
The ancestry of present day donkeys can be traced back to the wild asses that were initially hunted by humans for meat and skin. Some of these asses were probably tamed and bred in captivity, giving rise to the modern breed of domesticated donkeys. The first evidences of donkeys were found in Egypt around 4000 B.C. Soon thereafter, the animals spread into the Middle East, where they were bred with horses to produce mules. Gradually, donkeys spread throughout the world, and currently the population of these weight bearing mammals is about 40 million. China alone has around 11 million donkeys, closely followed by Ethiopia and Mexico. Various factors, like the growth of human population, rising gasoline prices, and the conversion of forests to farmlands, are all responsible for the still steadily growing donkey population in the world.
9. Horse (60 million)
Today, the total horse population in the world is estimated to be 60 million. As per reports by FAOSTAT, 10 countries in the world have over 1 million horses residing within their respective national borders. The United States is estimated to have the largest horse population in the world, with around 9,500,000 horses. In Europe, the Russian Federation has the highest number of horses at 1,319,358. China, Kazakhstan, and Mongolia in Asia, Mexico, Brazil, Argentina, and Columbia in Latin America, and Ethiopia in Africa also each have national horse populations of more than one million. Rwanda and Saint Helena are the two countries in the world with a reported "zero" horse population.
8. Tame Water Buffalo (175 million)
The domestic water buffalo originated in South and Southeast Asia, though now is found all over the world. Today, the total population of this species is around 175 million globally. The domestic buffaloes are classified into two types based on their habitats: the river type and the swamp type. Over 95.8% of this population resides in Asia, including both types of buffaloes. India leads the world with 97.9 million domestic water buffaloes, representing 56.5% of the total global population of these animals. 10 well defined breeds comprise the Indian water buffalo population, which primarily belong to the river type. Small parts of northeastern India also host the swamp type water buffaloes. Pakistan, China, Thailand, Philippines, Vietnam, Bangladesh, and Sri Lanka also have substantially large domestic water buffalo populations. Other parts of the world, however, have much lower numbers of this useful domestic species.
7. Domestic Dog (425 million)
It is estimated that the total population of ‘man’s best friend’ in the world is about 425 million. However, in reality the figures might be even higher, considering the difficulty in counting the large feral and stray dog populations that wander freely upon the streets of most nations of the world. It is, however, much easier to estimate the pet dog population in the world, primarily on the basis of reports generated by the pet food industry’s market research data. In the U.S.A alone, approximately 42.5 million households have one or more than one dogs, with the total number of dogs in that country alone exceeding 73 million. About 6 million dogs populate the homes of Canada. In Europe, France (8.8 million), Italy (7.5 million), Poland (7.5 million), the Ukraine (5.1 million), and the United Kingdom (6.8 million) have large pet dog populations of their own. Spanning parts of two continents, Russia alone also has around 12 million pet dogs. Brazil (30 million), Argentina (6.5 million), and Columbia (5 million) are the Latin American countries with the largest pet dog populations. Australian homes also own a large number of pet dogs. The figures from Asia, are, however, dubious. Many of the large Asian countries like China and India do not have strict registration requirements for dogs, and hence, despite having large feral, stray, and pet dog populations running in the millions each, it is even more difficult to arrive at definite figures for much of the region. Japan, however, has proven to be more advanced in this respect, and has about 9.5 million registered pet dogs. The most doubtful statistics are obtained from the African countries, where dog population statistics hardly exist from most of the continent's underdeveloped economies.
6. Domestic Cat (625 million)
Domestic cats have long been treated as the second most favorite pets of the human species, after only dogs. Today, these feline creatures have a thriving and growing population of 625 million worldwide, and in fact surpass dogs. Though the cat population is represented by pet cats as well as stray and feral ones, arrival upon their actual population figures is very difficult, as a proper census of stray and feral cats is often difficult to obtain. The cat population of the USA is estimated to be the highest in the world, with an estimated 76,430,000 cats dwelling in this North American country. China and Russia have the second and third largest domestic cat populations of the world, at 53,100,000 and 12,700,000, respectively. Brazil, France, Italy, the United Kingdom, the Ukraine, Japan, and Germany are other countries with notably large cat populations.
5. Goats (860 million)
There are about 860 million goats in the world, with 94% of these mammals occurring in the developing nations of the world. An astounding variety of goat breeds are to be found in the Asian and African nations, accounting for 81% of the world’s goat population. India, Pakistan, and China have the largest goat populations in the continent of Asia, while Ethiopia, Sudan, Nigeria, and Somalia lead Africa in the number of goats owned by their respective people. Goats are highly adaptable species, with different breeds surviving in different climates and topography. For example, 16% of India’s goat population survives in Rajasthan, the desert state of the country. There are around 351 goat breeds in the world, with Asia having about 146 indigenous breeds among them. 66% of these Asian breeds are concentrated in the countries of China, India, and Pakistan.
4. Pigs (1.0 billion)
The world has a substantially large, and continuously growing, pig population, estimated to currently be around 1 billion in number. Roughly 50% of the world’s pig population is concentrated in a single country alone, China, which has about 482,398,000 pigs. The USA also has a large pig population of about 64,775,000 pigs. It is also important to note that these countries are both among the leading pork consuming countries of the world. Brazil has the third largest pig population in the world, with 36,743,593. Among the European countries with the largest pig populations are Germany, Spain, and France. Besides China, Vietnam has the second largest pig population in Asia, which is about 26,261,400 in that country today.
3. Sheep (1.1 billion)
Numbering a little over a billion, these quadrupedal ruminants are kept as livestock in many homes and farmlands across the world. China has the largest sheep population in the world of 136.4 million, as per the United Nations Food and Agriculture Organization statistics from 2008. Australia stands second, with a population of 79 million sheep, significantly more than the human population of the continent, with 4 sheep per capita of the Australian population. India also hosts a staggering number of sheep, which is estimated to be around 65 million. Sudan and Nigeria in Africa also each host a large number of sheep. New Zealand and the United Kingdom are the other two countries among those with the largest sheep populations.
2. Cows (1.5 billion)
India’s love for her ‘holy cows’ is reflected in the cow population figures of the country. Roughly 301,100,000 cows, forming 31.21% of the total world population of this bovine animal, are present in India. Cow meat consumption and export is banned or restricted in most states of India, and hence cows are primarily kept in this country for their milk. However, the cow is not so lucky in other parts of the world where it has a thriving population. These include Brazil (213,035,000 cows) and China (100,550,000 cows) where cows are bred for meat, with Brazil being the world’s largest exporter of beef. Although India is also a leading beef exporter in the world, buffalo meat, not cow meat, is exported from the country and classified as such. Thus, roughly 64% of the 1.5 billion cows of the world are found in the countries of China, India, and Brazil collectively. Besides these countries, the United States, Argentina, Australia, Russia, and a large number of countries in the European Union have substantial populations of the cow themselves as well
1. Humans (7.3 billion)
With human tamed animals occupying all of the previous nine positions of most populous mammals on earth, it becomes quite evident that the topmost position in this list can be occupied by only one possible mammal. That is, the human beings that domesticated them themselves. Humans have thrived and proliferated to dominate the entire planet and its other species. Just a century back, the entire world human population was only 2 billion, and now it has boomed to 7.3 billion and still growing. The stunning figures are both shocking as well as awe-inspiring. Though human beings have wreaked havoc on the planet with their indiscriminate growth and exploitative activities, they are also the only species on Earth that have such high adaptabilities that they have occupied almost every possible niche on the planet, and in doing so dominated all of the other species of each of these regions. China, with a population of 1.36 billion, and India, with a population of 1.27 billion, are the two most populous countries in the world. The United States, Indonesia, Brazil, and Pakistan are others listing among the most heavily populated countries in the world in nominal terms. It is estimated that in this century, the global human population will break past the 10 billion person mark, increasingly straining the natural world and its resources in the process.