Consider our form and features now. They have changed since we were babies, but they are not newly formed: We have grown with the eyes and ears, limbs and heart with which we were born.
But what about our prenatal state? Were we with arms and legs, eyes and ears since the day of our conception? Of course not, is what most informed people would say today.
But there was a time, not too many centuries ago, when people spoke of homunculi: little human beings. These were microscopic creatures in the mother’s womb: all fully formed. They slowly grew and grew and became so big they were ejected from the mother’s womb. The word embryo originally meant a young swelling animal (in the womb). It was derived from a Greek word which means to swell or be full. This was the scientific equivalent of the idea that God created man: face, body, limbs and all, as a fully-formed creature.
Today most people brush off the idea of a miniature man or woman in the uterus, gradually enlarging in size, expanding like a three-dimensional photograph which becomes bigger to visible dimensions from a tiny film.
Up until the 18th century the notion of completed minuscule creatures bulging to become babies was widespread. This was known as the theory of preformation. The term evolution meant in those days the gradual enlargement of preexisting organs of the embryo: something very different from what it connotes today.
In 1759, a young medical student at the University of Halle by the name of Caspar Friedrich Wolff (born: 18 January 1734) published a dissertation entitled Theoria Generationis. In this, he rejected the preformation idea held by most scientists of the day, incurring their displeasure. He wasn’t allowed to lecture at the University of Berlin. Rather than be intimidated, Wolff went ahead and published a book in 1764, entitled Theoria Generations, expanding further on his original idea. His work gave scientific credibility to the notion of epigenesis: development from a homogeneous state to a very heterogeneous one.
Wolff’s work brought him fame beyond his Germany, and he was invited to the newly established scientific academy in St. Petersburg. The Russian Empress Catherine II who founded this institution used to import scientists from Western Europe at that time, somewhat as the U.S. started doing in the 20th century from all over the world. Wolff felt so satisfied in St. Petersburg that he became a Russian citizen.
Wolff’s view that there is a gradual development of the organism, plant or animal, from its initial creation, was based on careful studies of plants and unhatched chicks. It took several decades and translations before his insight came to be universally recognized. Now he is now regarded as the founder of scientific embryology. Students of anatomy read about the Wolffian body. Needless to say, his original explanations on how this development occurs involved ideas that are no longer acceptable.
Such is the progress of science: not always smooth or easy for those who bring about major shifts in our views about how the world behaves. Authority, be it of individuals or of institutions, can be quite powerful even in the march of science whose avowed goal is to understand how the world functions. But that quest is carried out in well defined frameworks, under clear cut parameters in different fields. Making breakthroughs and discoveries within the existing framework in terms of the generally accepted parameters is fine. But if and when one tries to change these, the task becomes horrendously difficult. Yet, and this is strength of science: Sooner or later, as a Hindu maxim declares, satyameva jayate: Truth alone will win.
January 18, 2016