Category Science

Gregor Mendel, a 19th century monk, is the founder of modern genetics. He is famous for his pea plant experiments which helped to establish some of the now accepted laws of heredity. Heredity is when certain traits like eye colour, height, and athletic ability are passed from the parents to the children. In biology the study of heredity is called genetics.

     In 1856, Mendel began studying hereditary features in pea plants, and concluded that all living things, including humans, passed on their characteristics to their children in predictable ways.

    Mendel grew, and tested almost 28,000 pea plants during 8 years of research. He came up with the terms recessive and dominant, to describe type of genes that are passed down through generations.

     Mendel’s findings, which he presented on meetings of the natural history society of Brno, in 1865, were rejected by his fellow scientists while he was alive. It wasn’t until later that his work was rediscovered and confirmed through further experimentation.

The English physicist James Joule studied the nature of heat, and established its relationship to mechanical work.

         He showed that the various forms of energy mechanical, electrical, and heat are basically the same, and can be changed, one into another. This is known as the conservation of energy, and the idea was proved by Joule in a series of experiments.

        In his early years, joule proved that heat produced in a small electromagnet built by him was from electrical energy, which was in turn, generated by mechanical energy which powered the dynamo. The principle of conservation of energy became the first law of thermodynamics, a field of physics that Joule is referred to as the chief founder of.

       Joule was the first person to calculate the speed of a molecule of gas, about 457 meters a second for oxygen at average temperatures. This would lay the foundations for the kinetic theory of gases in the future. Joule recognized the need for standard units of electricity. In fact, the unit of energy is named the ‘joule’ in recognition of his contributions.

Hermann Ludwig Helmholtz, a German physician and physicist, is best known for the law of the conservation of energy. He also made significant contributions to physiology, optics electrodynamics, mathematics, and meteorology.

         In 1847, he published his paper ‘On the Conservation of Force’. This was the first explanation of the fundamental concept of conservation of energy. His inventions of the ophthalmoscope allowed physicians to see inside the eye, and revolutionized the field of ophthalmology.

       Helmholtz was a keen mathematician, and in 1858 published the paper which provided a key to the fundamental structure of matter. He also investigated the physics of tone and colour perception. But above all, it is his theory of the conservation of energy that is his greatest contribution, for it is one of the broadest and most important generalizations ever known in the history of science.

Claude Bernard, a French physiologist, has been called one of the greatest of all men of science. Bernard was fascinated with the mechanics of digestion.

        He made a number of experiments in which he made opening into the stomachs of live animals in order to study their workings. His experiments resulted in a number of important discoveries, including the finding that the small intestine played a key role in the digestive process.

      His experimentation also helped show the significance of the pancreas. In 1857, Bernard discovered glycogen, the large molecule found in animals’ livers which acts as a reserve store of carbohydrates, and helps to regulate blood sugar. Bernard also studied the nervous system. While engaged in this research, Bernard made the important discovery that oxygen was carried around the body by red corpuscles in an animal’s blood.

     Bernard was one of the founders of experimental medicine, and played a vital role in laying down the basic rules of experimentation in the life sciences.

Charles Darwin was an English naturalist who is best known for his ideas on evolution. In 1831, Darwin set sail on the HMS Beagle, a naval survey ship. Darwin’s job was to collect plant and animal specimens from the countries the ship visited. The voyage took five years.

      For Charles Darwin, the most important part of the journey was the time spent in the Galapagos Islands which are the home to plants and animals that can’t be found anywhere else in the world.

      On his return to England, Darwin stated to piece together his theory of natural selection which explains how populations evolve. In 1859, Charles Darwin published his book ‘On the Origin of Species’.

     According to this theory, all species of life have evolved over time from common ancestors. Charles Darwin changed the way humans viewed themselves.

Jean Louis Agassiz, a Swiss-American naturalist, was an outstanding comparative anatomist. When he was only 21 years old, he published the work that launched him on his long and distinguished scientific career. It was titled ‘The Fishes of Brazil’ and it was the most important account of a local fish fauna published till that time.

       Later, Agassiz worked under Georges Cuvier, another brilliant comparative anatomist. Agassiz made extensive contributions to ichthyological classification, including of extinct species.

      Ichthyology is the branch of biology devoted to the study of fish. Agassiz also played an important role in the study of geological history including the founding of glaciology. He was a person with many interests- a biologist, physician, geologist, teacher, and most importantly, a prominent innovator in the field of the study of natural sciences.