So last week I mentioned that there is a difference between wild species and those that have been domesticated. You know that elephant you see performing tricks at the circus? That is still a wild animal. It may be tame, but it is not domesticated. There’s a difference and it’s important.
A wild animal is a species that evolved in the wild. It has the physiology, mental capacity, and instincts best suited to the environment it evolved in. An individual wild animal can become tamed (conditioned to be more docile and submissive to humans) but it cannot become domesticated. Domestication occurs not on one animal but on a population of a species.
- Domestication is a process whereby man has structurally, physiologically and behaviourally modified certain species of animals by maintaining them in or near human habitation and by breeding from those certain animals who seem best suited for various human objectives.
- Taming is a process whereby a wild animal is subdued into adapting and submitting to human control. Taming of wild animals can be accomplished by various methods but wildness is still there and can be triggered off by undue stress. There have been many instances of trainers being killed or injured by circus animals, particularly elephants.
A domesticated animal initially evolved in the wild, as all species did, but at some point humans started selectively breeding the species for certain desirable traits. A key trait would be a reduced fear of humans, since having the animal run away on sight of you wouldn’t accomplish much if you wanted to use it for labor or companionship. This selective breeding process usually takes many generations, at least, and the end result is a changed genetic composition when compared to the original species. A dog is no longer a wolf, for example, even if they still look similar. Yet, dogs and wolves can still interbreed. This means they are still very closely related; the genetic difference is very very small. As an example, the genetic difference between a chimpanzee and a human is around 98%, yet they cannot interbreed.
On average, domesticated animals have smaller brains than their wild counterparts. This may be a result of the selective breeding process that strives for a greater dependence on and less fear of humans. On average, domesticated animals are also initially smaller than their wild counterparts. I say initially because often size is a component that humans breed for. Bigger cattle or horses, for instance. Yet a reduced size when the domestication process begins is still common.
According to evolutionary biologist Jared Diamond, animal species must meet six criteria in order to be considered for domestication:
- Flexible diet
- Reasonably fast growth
- Ability to be bred in captivity
- Pleasant disposition.
- Temperament which makes it unlikely to panic
- Modifiable social hierarchy
Not all species can be successfully domesticated. For example, people have tried to domesticate the zebra for many years, but each attempt has been unsuccessful.
Feral animals are domesticated animals that have escaped, been abandoned, or were born in an outdoor environment from escaped/abandoned parents. By outdoors I mean while some of these feral animals escape into the woods and other wild places, many also live in human communities but without a human owner or home to live in. They survive by hunting, human handouts, and scavenging, often going through garbage.
Wildlife biologists and veterinarians as well as conservationists, are interested in wild, domesticated, and feral species for various reasons. When I was in South Africa several years ago, certain parts of various national parks had buffer zones where people were not allowed to have cattle or pet cats. The reason for no cattle is that domesticated cattle and certain wild species such as buffalo are still closely related enough to catch diseases from each other. A disease of particular interest is bovine tuberculosis. A buffer was created to reduce this spread. As for the cats, while cats would also be able to spread diseases, the main reason for this cat-limitation, I was told, was to prevent domesticated cats from breeding with African wild cats (Felis libyca), thereby hybridizing the species, which is considered one of the main threats (the other being habitat loss) of the species.
Here in the United States there has also been a big issue with both feral cats, swine, and horses. The horses of the Midwest are usually considered feral because it is most commonly believed they are descendants of those horses brought over by Europeans, not that native stock which is believed to have died out around 8,000 years ago. However, there is a case being presented that links these horses to those that originated in the Americas before European stock was introduced. This would make them wild horses, not feral. The debate is a hot topic in many circles because a label of wild or feral influences how the animals are managed.
These horse herds do not have owners and can usually be found on public land, where they may come into competition with privately owned cattle (also allowed on public land), for food and water. There is much scientific focus on damages/benefits of allowing horses on this land, how they compete with the cattle, as well as how the population may be controlled (catching for private sales and culling (controlled killing (this is highly controversial and I will be writing a post detailing it in the future)). This is a controversial area that wildlife biologists are very involved in.
Feral cats are also an issue, though there is no doubt in this case that the cats are indeed feral. These cats, often escaped or abandoned pets and their offspring, can rapidly increase in population. They also need to eat, and that can put the local wild species, such as squirrels and songbirds, in danger (much of the feral cat diet consists of garbage and human handouts, but the wildlife in the area can be affected to varying degrees depending on the population of feral cats and human handouts). This isn’t a safe environment for either the wild species nor the cats themselves, which are subject to harsh weather, food shortages, disease, and injury.
Feral pigs can cause great damage to agriculture as well as wild habitat. These animals eat almost anything so they can eat a variety of plants and then tear up the soil for seeds and roots. They will also kill and eat various animals such as fawns and eggs of birds or reptiles. These animals range widely in size and coloration because some populations are a hybridized mix of feral pigs and European wild boar, which were introduced for hunting pleasure.
Feral animals, wild invasive species, and even native wild species can all gain the attention of wildlife biologists. Our current human society has changed the landscape of many environments, limited predators, introduced species, threatened or encouraged select species, and overall directly affected the native ecosystems. Due to this, wildlife management is a field of study and research that is common for wildlife professionals.