The viewpoint of zoology

Two linked events today. (1) I decluttered  most of my Zoology textbooks and had a flush of nostalgia for the white coated world of academic science and, (2) there was a humorous TED talk by Ed Yong about parasite life cycles - many of which include taking over the brain of their hosts. 

I graduated as a Zoologist in 1972 when parasitology was still young. The mindbending complexity of parasite life cycles was appreciated but not in the richly detailed way that it is today. The parasitic life style evolved. It is natural. It is successful. It is ruthless and efficient. But it shows no compassion or mercy. 

The parasitic life stories abound with seemingly treacherous villains and evil monsters. And, according to Ed Yong, they are much commoner than was previously thought. Most of them are very small so they fall beneath the normal human radar. Out of sight, out of mind.

The parasitic life style is a mother nature option. Plants use photosynthesis to make their own food – they are autotrophic (self feeding). Animals have to eat other living things – they are heterotrophic (feeding on others). There are variations – carnivores (meat eaters), herbivores (plant eaters) and omnivores (meat and plant eaters). There are also predators and scavengers and the all important decomposers. It is a dog eat dog world.

The human body is that of a typical omnivore. This is most obvious in our teeth and our intestines which are designed to cope with the mixed diet our ancestors enjoyed when they were hunters and gatherers in the African savannah.

So what is the point of this story? Mother nature is not all nicey nicey. Parasites and predators have their right to be as nature intended. Evolution is amoral and ongoing. The devil is in the details. The fittest survive. If there is life there is death. If there is creation there is destruction. Humanity is not in control.

In about 7 million years the sun will go out and it will all be over. OR ……