Humans have been fascinated by animals since humanity's early days, just think about on how ancient Egyptian gods looked like, almost all of them had animal traits in order to point out certain aspects such as nobility, power, wisdom, or even death. However, in the future humans will more than likely posses the power of transferring certain animal traits into themselves. This technology is not science fiction, humans have used it in the past on plants or animals in order to make more beautiful and tasty fruits, or in order to increase milk production, and even for the sake of scientific research, as they created phosphorescent mice .
But why would we want to use this type of technology on ourselves? Well, the answer is simple: Evolution. It is a well known fact in the domain of genetic research, that once an organism is perfectly adapted to it's environment(like humans are) it decelerates it's evolution, as there is no longer a need for powerful specimens in order to ensure the species survival. But evolution can be accelerated through the use of genetic manipulation. Some might find this prospect grotesque, or as an insult to God, but I find it to be the next step in evolution.
Imagine that we could have wings, that we could breathe under water or see in the night and imagine humans that are capable of withstanding the effects of radiation or athletes that can run with the speed of a cheetah. Of course, at this moment scientists are not capable of making all these wondrous things, but in time and with research they could.
Sadly, there is also a dark side of genetic manipulation, it could be used to create perfect killing machines and other such horrors, but one must hope that those responsible of using this technology are not quite that mad ! The realm of the genes is a new one, steps forward must be taken with great care if disasters are to be avoided, for example, imagine people having exoskeletons like insects, that's not a very pleasant thought.
Until humans find the ability to morph themselves and grow wings or breathe under water, we shall have to find comfort in today's rather more mechanical technology that fits these purposes, and i must say that i find this to be a reassuring thing, past events have shown us that we can do terrible things with new technology.