My first point is their lack of intelligence, most animals are incredibly simple they can see, hear and touch but that is about it they are unaware of their very own existence. I don't thinks such basic beings should be treated with any rights when they are ignorant of everything that is going on around them why should we treat them with such unreasoned kindness when they are such simple life forms.Despite their lack of brainpower it is generally accepted that animals can feel pain but not in the same way as humans do they are unable to feel fear of what is about to happen to them and they also cannot remember vividly at all.
My second and most important point is the great use animals are to advancing the knowledge of the human race. Virtually every medical achievement of the 20th century relied on animals in some way. If we were to be stopped from using animals in testing it would be a great blow to scientific research.Without animal testing we would not be where we are today in medical knowledge we cannot deny future generations from curing the great medical issues and diseases of their time for the rights of these simple creatures.
Imagine if animals always had rights we would not have be any near where we are today in our scientific knowledge. Breakthroughs in the curing of diseases such as cholera, influenza and polio can all be accredited to the use of animals in scientific research I believe the lives of millions of humans are worth a few simple animals life's.Thirdly in the animal kingdom we can see how animals behave for ourselves they are savage beasts fighting for survival. Most animals haven't got the slightest bit of morality and sense of right or wrong why should we treat animals with compassion and respect when they do not even treat each other with respect.
Most animals will murder anything without a moment of thought or speculation of over what they just did was just because this is their way of life and always will be they will never treat us with kindness and so we should not treat them with it.Finally humans have been eating meat since their existence began it is the natural order of the world for animals to consume other animals and why should this stop know. It is the natural food chain of the world and humans are on the top. It is not possible for the whole of the human race to survive on vegetables alone, meat is needed to carry on the existence of the human race. So we cannot give animals such strong rights because it would make it nearly impossible to continue with our meat eating at the current rate it is so it would simply not work.In conclusion I do not believe animals should have rights mainly because they are so unintelligent they are not even aware of their own existence and because of their great use to science helping us cure the dangerous diseases of the past few and possibly the next few centuries.
There is also the matter of the human need for meat which we could not continue with if animals had rights and lastly and least importantly the way animals behave in their own kingdom without morals or control.
