Sign up ×
Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It's 100% free, no registration required.

Looking at ones that manage well alongside us human animals, such as dogs and cats, we see that this is possible for evolved, distant animals to have heritable, preferable traits around people. However, when especially looking at lions and the like, it doesn't seem to work out as well.

Some people have tigers as pets, but in general it is believed that they are more "wild" and not as tame and domesticated as other animals (such as dogs and cats).

Is it possible to selectively breed and enable any animal to be more like dogs and cats? Even sharks? Tigers? Alligators?

If domestication worked so well with dogs and cats, such as them living (for the most part) peacefully and well with people, wouldn't the process be beneficial for other animals so we could all live better side-by-side?

In short, can you theoretically get any animal to have heritable traits?

share|improve this question
I understand your overall question, but your last question doesn't really fit in: all animals have heritable traits. –  canadianer Jun 30 '14 at 20:32
Domestication of animals was not performed so that we live better side by side but because they were beneficial for human needs so we domesticated them. Best example is dogs that were used as protection for live stocks. I'm no zoologist to respond to your question but so long as they have a nervous system that can learn, I don't see what not. even snails and drosophila can learn tasks such as maze solving but that doesn't necessarily domesticate them so i guess it depends on how developed their NS is and what you define as domestication. –  Bez Jun 30 '14 at 20:41
have you heard of the 40 year long Russian experiment to tame foxes? Quite interesting. Have a look at it. –  WYSIWYG Jul 1 '14 at 4:19
Maybe the first question is. Are dogs and cats domesticated because they are predisposed to domestication? –  James Jenkins Jul 2 '14 at 3:22
It depends somewhat how we define domesticated - I keep flies in a lab, just as a farmer keeps cows in a field, but is this the same as training a pet? –  rg255 Jul 1 at 9:04

5 Answers 5

As the previous answers clarify, all organisms have heritable traits that may be manipulated through selective breeding. It is the pragmatics that can be prohibitively challenging. From an (zoo)archaeological point of view, few animals have actually been domesticated, and only recently in our species' history. The dog is an unusual case, perhaps domesticated 14,000 years ago; most domesticated animals only show skeletal changes within the last 10,000 years. Cats, compared to livestock's total dependence on humans, are 'barely' domesticated--they got used to humans while camping out in Egyptian storehouses where all the mice were, perhaps around 4,000 years ago, but even today a fluffy house cat will revert to a feral state if abandoned.

Many animals are behaviourally unsuitable for domestication. If an animal is dangerously aggressive, for example, they cannot be penned and isolated--so the many controlled generations it takes to reduce their baseline aggression cannot occur. Humans also tend to co-opt pre-existing social structures in a species, such as becoming the 'alpha' in a dog pack or the head 'ram' of a sheep herd. Species without a hierarchy or herd mentality are difficult to control and keep track of, and so do not lend themselves to human care.

You mentioned tigers in your question. Tigers have little to offer people (other than pelts), they're massive/aggressive, and they're jungle loners. You can't raise a herd of tigers; they'll kill each other and the survivor will kill you. That they're carnivores is also challenging, since a carnivore is much more expensive to feed than a bunch of grass-munching sheep. Altogether, there was never a situation in prehistory that would have turned tigers into giant house cats. House cats eat unwanted mice; tigers eat your cattle (and children). The occasional tiger 'pet' won't change that.

Domestication, outside of recent experiments (like the Russian foxes mentioned above), has always been a protracted, indirect process. People started interfering with animals that were already useful in some way(s). Dogs offer warmth, hunting aid, defence, transport, and (in a pinch) food. Alligators, tigers, and sharks are not useful enough to make the danger and cost of raising them worthwhile. Even if you did eventually produce a 'human-friendly' shark, there would still be a 'wild' population ready to eat you--and your complacent pet sharks, too!

For a very readable explanation, try the chapter on domestication in Jared Diamond's (1997) Guns, Germs, and Steel.

share|improve this answer

I understand the question as "can you get any animal to have heritable traits selected by humans?"

This definition of domestication implies that a population of animals can be bred for a sufficiently long period of time, so that humans can select hereditary traits that fit their needs. Humans could provide selective pressure that creates a new variety with different traits. So according to the laws of evolution, I would say it could theoretically be done for any living being.

But there may be species that could be reluctant to such a control, e.g. animals that we have difficulties to reproduce in captivity for whatever reasons (polar bears?), or isolate from their wild congeners (genetic isolation is a generally a pre-requisite to domestication). For them, domestication could take too much effort or a longer time than humans would be willing to spend.

share|improve this answer
So, are you supporting his theory that all animals could be domesticated? Just that some take more time than others. –  The Last Word Jul 1 '14 at 4:12
It really depends on the definition of domestication. I'll edit my answer to clarify. –  biozic Jul 1 '14 at 8:18

As everybody, I don't fully understand your question. Can you please add your definition of domestication?

Would you consider domestication as soon as human can select for heritable traits? If yes, then the question may be split in two:

Do all animal populations have heritable traits?

Yes! But Depending on what kind of traits you want to consider no variance (yielding to no heritability) may exist in the population. For example, you'll have a hard time to select crocodiles to have fluffy hair as there is no variance in "hair fluffiness" in the population. Crocodiles have no hair.

However, some practical issues exist. For example, it might be hard to select for a given behavior if the animal is so small that we can hardly observe them during a sufficient amount of time to know whether or not the individual display this behavior. Typically, it might be hard to select for specific traits in a population of a species that live inside another species (endosymbionte, endoparasite).

Are humans able to breed any animal species?

No, we're not! Many species do not breed in captivity or do not even survive in captivity. This is due to our lack of knowledge of the ecology and social behavior of the species in question.

share|improve this answer

Not all animals are equally predisposed for domestication. To be easily domesticated, animal should have:

  1. Flexible diet - and not compete with humans for food
  2. Reasonably fast growth rate
  3. Ability to be bred in captivity
  4. Pleasant disposition
  5. Temperament which makes it unlikely to panic
  6. Modifiable social hierarchy

Wikipedia link above has plenty of details.

So sharks, tigers and alligators are (according to above) are NOT good candidates, because of 4 and 6 at least. Alligators are bred in captivity in farms but are not really domesticated.

See also dates and places of domestication.

share|improve this answer
There are also two very different kinds of domestication. Most domesticated species we keep around as a source of food, so their domestication equates to being able to conveniently keep & raise them. A few we form working partnerships with: notably dogs & horses, but to some degree camels, draft cattle, llamas, and a few others. –  jamesqf Jul 1 at 21:25

No and yes.

What you perceive as domestication has a lot to do with intelligence or even social intelligence of animals.

Common fish is too stupid (from our point of view), to have any social bond with humans. Mammals are usually much closer and have similar structure of intelligence and patterns of behaviour.

That only if you consider domestication as something more and not just human utilization as with breeding fish for food, spiders and snakes for fun (or even snakes for rat-catching, as some African tribes did according to wiki).

So not all animals could be domesticated, they need certain qualities, mostly connected (or we are connecting them) with intelligence.

However, once you look at mammals, which usually have enough social intelligence, you could breed them into domestic animals. It would be hard, there would usually be no other purpose than "We can, so we do", but you could. There were various experiments. One is famous Russian experiment with foxes, another is infamous Hitler's experiment with cows (experiment with bringing back Aurochs, Heck cattle, cows were "undomesticated"). There, in controlled environment, true genetic plasticity of behaviour were showed.

Note that as other posters wrote, this is theoretical. In nature and by natural means, domestication was always hindered by immediate usefulness (not even potential future usefulness). Most of domesticated animals are highly social in their natural form and not very aggressive. Even big cats are quite close. Tigers not as much as cheetahs, which were traditionally bred (or kept as pet) from ancient times.

In short, can you theoretically get any animal to have heritable traits?

All animals have heritable traits. That's genetics.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.