Biological systematics classifies animals according to its own standards. So far about two million animal species have been distinguished. Each species has distinguishing characteristics and study of a few members of a species gives us general information about the whole of that species. For example, study of a pigeon gives us general information about all birds from nightingales to eagles, from grebes to albatrosses.
Systematic study of a species reveals that the assertions of being more or less developed are of relative nature. Also, study of the general control mechanisms in animal bodies shows a relative complexity in their metabolic and, especially, hormonal and nervous systems from one-celled organisms to mammals. It is difficult to attribute this complexity to chance or coincidences. Determining an entity of such complexity and adaptive effectiveness requires an absolute knowledge, will and power.
The standards by which to determine the degrees of development for animals vary from species to species. For example, with respect to the sense of smelling, sharks, according to our present knowledge, are relatively the most developed among vertebrates. Compared with a shark which can smell a drop of blood in the sea from a distance of about 25,000 feet, man is very much less developed. If we judge the degree of development according to the sense of smell, in place of men or monkeys, sharks will be the first. Whereas, with respect to the sense of seeing, eagles are much more developed than sharks, as well as than men and monkeys. An eagle can see a rabbit on the ground from a height of about 6.000 feet. Also, a bat which catches its prey in the dark with its ultrasonic equipment and a rattlesnake which catches rats with its infra-red eyes are far more developed than human beings in their respective areas of specialization.
Supposing a man was to enter the world of flies, what would flies say about him? ‘How simple and undeveloped that being is! He does not know how to fly. Even with the planes he made, he cannot fly as perfectly as we do. We turn somersaults, alight wherever we wish and take off very easily. Even one-tenth of the subtleties of art in our wings is not to be found in his most elaborate devices. Despite his abilities, skills and knowledge, he is completely unable to make one wing such as ours!
Would it not be true for a honey-bee to say of us:
‘Those clumsy ones can draw with tools and only after calculations the hexagons that I can make so easily and exactly identical to one another. They cannot make so sweet and healing a substance as honey that I produce in great amounts.’ Again, should a microbe or virus not consider itself as more powerful or developed that man seeing that it can cause him to die? With respect to their ability to swim and live in water, are not fish more perfect or developed than us? But then animals living on land are surely more developed than fish in respect of the mechanisms enabling them to live on land.
When we consider the world of insects, we are amazed at the degree of social organization they have achieved: the solidarity in the social life of bees, ants and termites, the communication among them, the absolute obedience of the individual to the commands of the collectivity, and the fulfilment by each individual of its duties to the community- compels us to wonder whether insects or human beings are more developed in this respect. It is for this reason that some socio-biologists tend to think of a society of insects as if it were an individual organism, operated by a single brain, the individuals in the community functioning like separate cells within the larger single organism.
Those who classify creatures according to the complexity of their brain structure and faculties assert that the more complex a brain is, the more developed the animal. However, even though the weight of the brain or the ratio of brain weight to general body weight sometimes appears to confirm this assertion, it usually leads on to wrong conclusions. Those who argue that the mammals whose brains are smaller than the human brain are simpler than human beings, forget that the main difference between human beings and mammals lies in man’s memory and capacity of thinking and speaking, and that there are great differences among the intellectual capacities of human beings. Also, every human being is different from others in many ways-in character, ambitions, attitudes, etc.
It is function which determines the form and type. That is, an architect does not determine the function of a building after he has built it. On the contrary, he builds the building according to the function it will serve. In the same way, the structural perfection of the human brain corresponds to its functional perfection. That is, man did not become man after he had acquired his brain capacity or complexity. Rather, he was given a brain according to his functions with respect to other creatures and to the duties he was expected to perform. Thinking, as evolutionists do, that brains in animals grew more complex and their ‘intellectual capacity’ increased in parallel with the line of evolution, means attributing all the intellectual faculties and activities like thinking, reasoning, imagination, speaking and so on, to the brain as a physical entity. This is the crudest sort of materialism and reduces man’s existence entirely to matter, rejecting the existence of the spirit and spiritual dimension of man. Also, it is not possible by this hypothesis to explain the differences among human beings in their intellectual capacities, desires, ambitions, and character. If it were possible to increase or strengthen man’s intellectual capacities by making him a bigger and heavier brain, rather than educating him, would it not be more reasonable to try to find ways of enlarging his brain or, as some assert, enabling him to use a greater part of his brain?
How can we regard it as simpler or ‘less evolved’ that in the cytoplasm of one-celled organisms many vital activities like digestion and excretion are carried out? As a sma11 watch is usually more intricate and requires more artistry in its production than a big clock, it may well be said that one-celled animals are more complex or difficult to come about than large, multi-celled ones. Again, although it seems at first sight that the more the number of cells increases, the more complex the creature grows, no one can say that an elephant is more developed than a mouse. Both being classed as mammals, with respect to their bodily activities, one cannot be considered more developed or simpler or requiring more artistry than the other. This leads us to reflect on the following Qur’anic verses:
God does not disdain to coin even a gnat as a parable, or a larger creature. As for those who believe, they know that is the truth from their Lord. But those who unbelieve say, ‘What does God wish to teach by such a parable?’ He leads astray many thereby, and guides many. He leads astray only the corrupt. (al-Baqara, 2.26)
O mankind! A parable is set forth, so listen to it: Surely, those whom you invoke, apart from God, will never create a fly even if they combine together for the purpose. And if the fly took something from them they could not rescue it from it. Hence, weak are both the seeker and the sought! (al-Hajj, 22.73)
It is foolish to regard the bony scales of fish as simple while regarding the pituitary glands on the skin of frogs as developed and the scales of lizards as more developed and the feathers of birds as much more developed and the hair of mammals as the most developed. It is no more than a speculative assertion that those protective parts of the bodies of the animals mentioned evolved each from a simpler one by chance. Is it not more reasonable to accept that each species of animals was given a particular body with its particular parts and systems according to the function it would serve among creatures and the environmental conditions to which it would be best adapted and adaptable?