Evolution - Thoughts from Darwin’s Origin of Species

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“The love for all living creatures is the most noble attribute of man.” - Charles Darwin

Reading The Origin of Species is not another random decision I have made this year because I have always been fascinated about animals, species and their chaotic similarity between each one of them. Evolution is not just another theory for the origin of species, where there can be multiple possibilities but evolution is an obvious thing which explains with at most rationale. Though the book contains a lot of repeatable concepts, (not sure whether it is from the raw text of Darwin or publication) I listed a few things which I find crucial and find them after I read the book. I hope you already have good idea of fundamental evolutionary concepts such as species, variability, inheritability and natural selection.

Mandatory sibling photo to represent Evolution, Shot by iphone 13, Loc: Conoor, Tamil Nadu, India . Wide Camera 26mm, f1.6 , ISO 50, ¹⁄₄₁₄₉ s

Nature’s pressure is greater than Human’s

Pressure such as separation between the same species, climate, land movements which are caused by nature are much more effective than human-made pressure such as agriculture practices, breeding and other factors. In childhood, I observed in my village that the chickens which are in our house are different colours than my neighbours which is different from their next. But it will be like a spectrum after some point, where the colours will have some relationships, more and more you travel to next next houses. I often imagined what if there is defined separation to protect reproduction between each house chicken. After a millennium we might have strong variations in colours and behaviours, which will eventually lead to the birth of subspecies. There are a lot of examples where humans created a lot of subspecies via domestication and breeding practices, both intentionally and unintentionally. You can find more examples from Darwin too.

Nature’s pressure when combined with a long period of time creates a diverse set of species sometimes even genuses itself. One such example is Australia where the land is separated for millions of years and created unique species. So it might look obvious that nature is more powerful in creating variance than humans. But often the counterargument made around perfectness and the absence of randomness in human-made pressure. For example, dog breed councils are known for their perfectness in keeping pure genetics in breeds, which might support the argument above. But nature’s pressure ensures the resilience, suitability of the environment and importantly long-term survival of the species, while humans are just for a purpose and artificial ecosystems which is heavily simulated and with zero intention of creating new species and contributing to biodiversity.

Not all similar traits between different species came from a common ancestor

Convergent evolution is slightly new to me which defines, if a trait is common in different subspecies or different variations, that does not mean the trait is inherited from the common ancestor, rather they get that characteristic after they branched out. The venom of snakes might be a good example for this topic, though Darwin provides complex examples. Most of the subspecies and branches that happened between them can be simulated in mind. For instance, when I think of man and monkey, the common ancestor has binocular vision which is inherited by both of them, this is true. But some species of snakes in Africa and Australia are branched way too early but become venomous at a later point in time, which is made by the natural pressure of that particular ecosystem. It almost broke my belief in randomness in natural evolution. I always thought that traits are highly random and will never happen again even if the ecosystem and situations are the same, but nature mostly chooses the same possible traits which can survive in different epochs and places.

Correlation is often overlooked

Correlation in evolution is defined as the relationship between two traits when they evolve. If two traits are highly correlated then they both evolve together. For example in mammals, the size of the body and the size of the brain are correlated, which means if a big body provides a high amount of survival then the big brain is also retained during evolution. This is highly used in the breeding of domestic animals to examine the traits in breeding.

Below is the imaginary correlation matrix, I made for the Feline family. I am just a software developer, not a Darwin or evolutionary biologist, hope it makes sense. The below matrix illustrates the relationship between different traits and how they are correlated.

Here size of the body is correlated largely with meal size, which suggests that larger cats need larger prey and it branches out the big cats from smaller cats because of the nature of the territory in which prey size varies. The more positive correlation traits tend to increase together, the less might lead to branching out for better diversity. The reason why I mention this is overlooked is, that during casual conversations on evolutions, nature’s pressure is mostly discussed on a particular trait, but not with respect to other traits’ contribution to the trait which is discussed.

These are some of my thoughts as of now, until the 5th chapter. Will try to come up again once I complete the book, hope it happens.