Because we are Homo sapiens
Asking ‘why’ is an important trait we have. An equally common trait is answering that question with a ‘because of’ reason. This ‘because of’ answer is, I assume, is a typical sapiens-centric way of thinking.
As important as this way of thinking is, when it comes to our origins, it is a syndrome we all, including evolutionary scientists should at best avoid without proper qualification.
When it comes to evolution, we can never say something developed BECAUSE OF this or that reason unless the explanation is on intracellular level (genetic). Evolution has no mind of its own with which to decide which way to turn. Changes in the phenotype may happen, but these are chemical and of environmental (in terms of the cell) origin.
A deviation from the norm may develop at some point. Completely random and peculiar to a specific conception. Random does not mean non predictable. It happened. Full stop. It can happen and will happen in any of the billions cell divisions in the life of the individual organism. From the first cleavage to the last somewhere after death.
The reason why something exists in this particular time-frame is because it survived to be here. Countless may cells may perish, but some survive. Many may be of no consequences, some may cause malfunction, some many even cause the death of the individual. Irrespective of the deviation, if lucky to find a niche in time and space in which to survive, it may procreate with or not a reproducible copy of that change.
Finding a niche in space and time to habitat are completely dependent on what the environment throws at it. As long as the habitat stays reasonable stable. But conditions can change unpredictably and that change can be brief or permanent. While there is a reason for the change, it invariably is caused by a random extraterrestrial event. (Why else a placid spinning globe suddenly become reactive, a sudden temperature shift, a pole reversal. etc. But that is another story.)
That deviation, if it is carried forward in subsequent populations, will be of no consequences unless one time in the future gets challenged by a change in conditions. The availability of food and water, density of predators being the chance of bumping into a predator and a climate to survive in.
Because of our proclivity to answer complex questions in simple one-liner terms we do not create a truer understanding of evolution. That is why the lay person keeps on being baffled by the chicken-and-egg ‘mystery’, the complexity of the eye, why the giraffe has a long neck etc. Why misconceptions persists.
The process of evolution as we understand it today is a complex concept, just as the interstellar space within we exists. We need to internalize these concepts in order to take the next step in understanding evolution just as stepping on the moon is reality..
Servaas de Kock 2015
This piece is by no means complete. Will continue sometime.