Darwin, Mendel, Landsteiner, and Arsuaga: Key Figures in Science

Darwin and the Theory of Evolution

General Facts About Darwin

• He explained how natural selection could produce evolution.
• The HMS Beagle adventure: a five-year round-the-world trip to make maps.
• He recorded data (notes and pictures) and collected specimens.
• The experience in the Galapagos Islands. Darwin was shocked by the great variability in the islands.
• The famous Galapagos finches: beaks designed for different food. Did they come from just one species?
• He came up with an idea that was not new, but he was the first one making enough arguments to persuade people that evolution happens.

History of Darwin and Wallace

Darwin was born in 1809 in Shrewsbury, England. He belonged to a wealthy family. His father and grandfather were both physicians. He started studying medicine at the Edinburgh University, but finally, he neglected his studies to become a naturalist (Erasmus Darwin, his grandfather, was a poet and a naturalist too. He influenced Darwin with his evolutionary ideas). Charles Lyell's uniformitarian ideas (he said that geology is not so fixed – Darwin thought that species could evolve just like the landscape did) and the work of a famous economist, Malthus (number of individuals increases faster than the food supplies – fight for resources) were essential for his theory. When he was 22 years old, he enrolled as a naturalist in the Beagle. This voyage changed his life. Back at home in his new house at Down, he ordered all the collected data and wrote his book “On the Origin of Species” in 1859. A year before the publishing of the book, he received the work of another scientist called Alfred Russell Wallace. This naturalist had drawn the same conclusions as Darwin. He explained his theory in the British Association for the Advancement of Science. Huxley and Hooke supported it, but many other scientists argued against Darwin's idea. The two statements of his theory: The survival of the fittest and natural selection. Darwin himself exposed the three weak points of his theory:

• The register of fossils in rocks was incomplete.
• The age of the Earth was not worked out accurately.
• What's the origin of the variation? – they didn’t know about genes yet. Genes (Mendel).

Lamarck's Example

Previous from Darwin. Lamarck’s theory: the function develops the organ. Inheritance of acquired characters. He didn’t know anything about genes.

Mendel's Three Laws of Heredity

A number of hypotheses were suggested to explain heredity, but Gregor Mendel, a little-known Central European monk, was the only one who got it right. His ideas had been published in 1866 but largely went unrecognized until 1900, which was long after his death. His early adult life was spent in relative obscurity doing basic genetics research and teaching high school mathematics, physics, and Greek in Brno (now in the Czech Republic). In his later years, he became the abbot of his monastery and put aside his scientific work. Although Mendel's research was with plants, the basic underlying principles of heredity that he discovered also apply to people and other animals because the mechanisms of heredity are essentially the same for all complex life forms.

Karl Landsteiner and Blood Groups

Karl Landsteiner was an Austrian biologist and physician. He identified the three blood groups (A, B, and C, which was later 0). One year later, they discovered group AB. Blood transfusion between the same blood groups worked, but there was cell destruction between different blood groups. Based on his findings, the 1st successful blood transfusion occurred in 1907. He was awarded the Nobel Prize in Physiology or Medicine in 1930.

Luis Arsuaga and the Atapuerca Archaeological Site

Luis Arsuaga is the director of the archaeological site of the Atapuerca caves since 1991. He is an expert in the evolution of locomotion and childbirth in humans. He discovered, along with his team, the best-preserved skulls to date and a male pelvis, as well as remains of Homo antecessor. Atapuerca: remains of Homo antecessor, sapiens, and heidelbergensis.