It is my opinion that there have been 4 great scientific discoveries in the last 100 years that have dramatically changed the way we understand the world. The first is Ernest Rutherford’s work on the structure of atoms and their decay. The second was the discovery of the DNA alpha helix by Watson and Crick. Thirdly was the ability to sequence genomes. Fourthly is the very recent discovery of gravitational waves that may lead to revelations about the universe(s), past and future, that were never thought discoverable.
However, the discovery of how to sequence entire genomes is the one that I want to mention today. The importance of this scientific breakthrough cannot be understated because it transformed Darwin’s ideas from theory to a fact. The ability to sequence entire genomes of complex organisms (including humans) has put beyond question or debate that Darwin was largely on the mark when he theorized that species evolved from species that came before. There is no longer room for discussion about creationism or intelligent design because genetic sequencing has now debunked them beyond any doubt and they now belong to the history books along with claims like the earth is flat and illness is caused by evil spirits.
So knowing that this claim will both upset and be rejected by some people, why do I put my neck on the line with it?
Since my post on March 22, I have been privately corresponding with a regular reader who felt offended by my belief that shoeing some horses in some circumstances can be a better option that leaving them barefoot. The essential argument they presented is that the hoof of a horse is both complex and brilliant. They argued that the hoof is an amazing piece of engineering that makes it optimally designed to carry out its function. Therefore fitting metal shoes to a hoof interferes with the optimal function by altering the way it interacts with the ground. The bottom line of their argument is that horse’s feet were designed to be perfect as they are for what they need to do. They believe that shoeing a horse hinders the hoof function for which it is perfectly designed to do.
I reject this argument for a very simple reason.
For an animal to possess any anatomical or physiological feature, it does not need to be perfect, it only needs to work. If we focus on the feet of horses, the hoof has many design flaws that leaves it susceptible to problems like laminitis, pedal osteitis, bruising, infections, arthritis etc, (sometimes caused by humans and sometimes not).
The hoof is designed well enough to support the frame of a horse and allow movement. But it fails in other ways. Just because a mechanism such as a hoof is the culmination of many thousands of years of evolution, does not mean it is perfect. It doesn’t need to be perfect.
Evolution only needs to create a design that works well enough for the animal to be able to successfully reproduce. The hoof only has to fulfill its function adequately to ensure a horse from lives long enough to pass its genetic characteristics to the next generation. This does not mean it has to be a perfect or optimal design. That’s not how evolution works.
This is true of virtually every function of an organism – they all have strengths and weaknesses and being perfect for the job hardly ever exists. I use to set an exam question each year for honours year physiology students asking them to outline a better design for human sight or locomotion or kidneys or skin etc (it changed each year). With a little thought it was an easy question to answer because there is a range of ways to improve each system. For any system to exist it only has to function well enough to get the organism to the stage where it can reproduce and pass along our genes.
If you understand this fact of life you also understand that we can sometimes help overcome the weaknesses that nature has created. And example of improving upon nature might be fitting shoes to a hoof to make a horse more comfortable and functional. Another example is when good dental care can make a horse more comfortable, make it healthier and prolong its life. Perhaps another instance is parasite control – even in wild herds parasites (such as ticks) can be a major problem that both hinders the quality and length of a horse’s life.
Maybe this post is more of a soap-box type lecture than most, but my recent exchange with a reader prompted me to realize that there are people who believe that horses are made perfect and human intervention can only get in the way of their perfection. I think that concept is a hard one to justify when we look at the facts. That is not to say that sometimes we aren’t that cause for making life harder and more miserable for horses, but we also have the ability to make their life better too. The choice is ours.
Photo: Speaking of perfection ….