Sunday 8 April 2012

Evolution of Behaviour and Influencing Factors in Dogs

Evolution of Behaviour and Influencing Factors

In this report I am going to be explaining the evolutionary development of behaviour in dogs and discussing how internal and external factors can influence these behaviours. All dogs descended from wolves around 135,000 years ago; the domestic dog emerged through selective breeding, and there are some breeds which are much more closely related to wolves than other breeds are. Due to all of the selective breeding and human influences this has caused the behaviour of dogs to change dramatically compared to its ancestors, wolves behaviour.


The link between environment and behaviour -

First of all I’m going to talk about morphological adaptations which are how an animal has changed to suit the changing environment gradually, over a period of time. As the dogs have become more adapted to the human environment some species have lost most of their predatory instincts and no species of domesticated dog has the predatory drive of a wolf anymore. Over time they have also become a lot more docile and affectionate than wolves. Other differences in their behaviours due to the environment are the domestic dog’s excessive need to scent mark, a difference in fighting styles due to domestic dogs becoming adapted to having to fight alone whereas wolves are pack animals, the domestic dog’s acceptance and tolerance to strangers etc. Dogs have also adapted to bark and communicate much more frequently than wolves as wolves do not bark.

Another way in which a domestic dogs environment has changed from that of a wolf is the competition for resources; dogs do not have to compete for food or territory etc. anymore because humans provide them with everything they need, whereas wolves compete for everything. This has caused a massive change in the independence of the dog, wolves are becoming more and more intelligent and independent as time goes on and the evolution of the domestic dog is doing the complete opposite. Their brains have become smaller compared to the wolves because they do not need/ use their senses  as acutely because they are human commanded whereas wolves are becoming more and more skilled in these areas because they need these senses to survive. Wolves are also more independent in the sense of solving their own problems because during the domestication process dogs have suffered a reduction in their intellectual capacity because they do not need to think as much for themselves anymore.

Heredity of behaviour -

The next thing that I am going to talk about the heredity of behaviour. This is how behaviours have been passed on in genes even as dogs and wolves have evolved. This is mainly instinctive behaviours in domestic dogs which have been passed down in the genes from wolves; one example is the pack instinct. This is evident when you have more than one dog in your home, one of the dogs will be in control of the other/others for example controlling who can drink or eat first and being able to stop the other dogs playing in an instant. This is a behaviour that is commonly shown in wolf packs and is known as the hierarchy; also the leader is not necessarily the oldest or biggest. There is only so much an owner can do to try and change heredity behaviour.

Another example of a dog behaviour which has been passed on in genes from the wolf is a dogs search for freedom. Dogs can escape the most secure of gardens; can jump over fences and digs holes under them. This is because like a wolf they like to be able to run free and they associate this with being safe. This can also explain why some dogs rebel against leads and things because they don’t like the feeling of being restricted and their instinct is to fight it.

Sex is also a hereditary behaviour because there is an ingrown sense in all dogs to reproduce and establish a future for its breed. This can be seen in domestic dogs when they mark their territory with urine as you take them for walks and around the garden because this is to let other males know that you’re the alpha male in the area and to let other dogs of the opposite sex know that they’re willing to mate.
Another good example of hereditary behaviour which has been passed down from the wolf in the dog’s genes is a dog’s instinct to guard and steal food. This comes from when dogs used to be in the wild and they had to hunt and protect their own food otherwise they would starve because they could never guarantee when the next meal would be.

The last example of a hereditary behaviour in dogs is the ability to swim. This has been passed on in the genes because it is in a dog’s instinct to survive and being able to swim gives them a big advantage in escaping from other predators etc. 

Internal factors influencing behaviour –

One internal factor which influences behaviour is hormones; this is less so in domestic dogs than it is in wolves because people tend to interfere and reduce the hormones in their dogs so that they are calmer and easier to handle. Examples of behaviours caused by hormones are scent marking mainly in male dogs and false pregnancies in female dogs.

Another internal behaviour which affects behaviour is illness or pain. If a dog or wolf is in physical pain they both tend to act overly aggressive; this is to keep other animals and people away from them because they are vulnerable. One difference that has occurred between wolves and dogs when they’re in physical pain is that domestic dogs are a lot more vocal about it and will howl and cry and try and alert humans that they are in pain whereas wolves would most likely try and get on with it. Also if a dog or wolf has a disease some of the symptoms could be changes in behaviour such as brain tumours will cause a dog or wolf to change its temperament and it can also cause a dog to walk in circles a lot and to sleep a lot or be very active.

Fear can also cause a dog or a wolf to behave in a certain way. It can cause both to become a lot more aggressive towards what they are fearful of. One difference between dogs and wolves in this aspect is that dogs are more likely to hide and cower from fear, sometimes behind their owner whereas wolves are a lot less likely to run away.

Another internal factor that affects behaviour is stress. Wolves are more use to certain types of stress than dogs and vice versa. Most domestic dogs have become use to being confined spaces whereas if you were to put a wolf in this situation it would probably become increasingly aggressive, pace a lot and not eat etc. Both dogs and wolves become stressed when they feel threatened which can cause them to run or to become extremely aggressive.

External factors influencing behaviour –

One external factor which affects the behaviour of both dogs and wolves is the presence of other animals. This can cause different reactions in both dogs and wolves but it can also cause similar behaviours. In the presence of another dog, a dog’s behaviour would change because the dog may become defensive, they could become aggressive (especially if it was two males) and if it was a female in season then a male may be affectionate towards her or try and mate with her. This is the same for when wolves meet other wolves. One difference which shows how dogs have evolved is that sometimes a domestic dog will be fearful of other dogs and see humans as their family and protection whereas this never happens with wolves because their family is their own kind. Dogs behaviour can also change when they encounter other types of animal; dogs are much more likely to except other animals such as cats, rabbits or birds and see them as companions whereas wolves will see these animals as prey or competition and so will be aggressive towards them and their will be constant conflict. Domestic dogs easily adapt and learn to accept other animals whereas wolves are unlikely to ever be able to do that because they have to be so competitive to survive.

Seasons can also affect a dogs behaviour, for example in winter most domestic dogs have evolved to grow a thick coat of fur and then to shed it in the summer. This changes their behaviour because this means that they can be active all year round whereas with wolves such as the grey wolf which has thick fur are only active during the winter, in the summer they become irritated and sleep and spend more time in the shade. This also applies for different breeds of dog because some dogs have been selectively bred to have very short, fine fur and others have been bred to have long, thick fur. Seasons can also affect a dogs behaviour because of breeding, in the breeding seasons females come into heat and males are looking for a mate and so therefore scent mark more etc. This applies for both wolves and dogs but less so for domestic dogs now due to human interference.

Another external factor which can affect dog behaviour is daylight. Domestic dogs are a lot more active during the daytime because they have evolved to be awake when humans are awake and to sleep when we sleep. On the other hand wolves are most active at dusk and at night because this is the best time for them to hunt because they can hide easily and be more camouflaged.
Weather can affect a dog’s behaviour because wolves survive outside and so they can deal with extreme weather conditions and are used to them whereas domestic dogs are mostly indoor animals. They can be especially fearful of stormy weather such as thunder and lightning and this can cause them to become aggressive or to hide.

Lastly, humans can affect dog and wolf behaviour but in completely opposite ways. Wolves are fearful or humans and tend to stay away from them most of the time but can also be aggressive towards us because they see us as an enemy. On the other hand domestic dogs see humans as their friends, protectors and leaders and they are a lot friendlier towards us and accept us.

Overall, dog behaviour has evolved massively compared to wolves now; there are many distinct differences between the two. Some of this is good such as how domestic dogs trust humans now and some of it can be seen as bad for example how their brain has shrunk compared to the wolves. Even though dogs have evolved they still have their instinctive behaviours from their wolf ancestors which have survived through generations of selective breeding. This is the reason we know that dogs have evolved from wolves.





8 comments:

  1. During your external factors section and under the season paragraph, you have incorrectly stated that wolves do not shed there fur during the warmer seasons, this is incorrect as wolves will shed and regrow there fur every year to allow them to hunt the abundance of prey during spring and also stay warm during winter.

    ReplyDelete
  2. This comment has been removed by the author.

    ReplyDelete
  3. Excellent work, did you happen to go to oaklands college?

    ReplyDelete
  4. What references did you use for this?

    ReplyDelete
  5. very interesting and well set out
    Thank you, It was a great help for my studies

    ReplyDelete
  6. really interesting and informative.

    ReplyDelete
  7. I wanted to thank you for this great read!! I definitely enjoying every little bit of it I have you bookmarked to check out new stuff you post.

    K9 Training Baltimore

    ReplyDelete