key concepts in the exhibition1. Darwin's greatest tool was his ability to observe and analyze. Darwin made great discoveries using basic scientific tools like a magnifying glass and notebook. But his most powerful tool was his mind. His intense curiosity about the diversity of species and their range of adaptations to different environments led him to a new understanding of the world around us—and our place in it.
2. Scientific knowledge changes over time, as scientists test, refine, and add to what is already understood about the world. Before Darwin, many 18th century naturalists saw order in nature, and a few even recognized that some form of evolution occurs. Darwin's breakthrough was his discovery of the underlying mechanism, which he named natural selection. New scientific tools and new fields of study, such as molecular biology and genetics, have greatly advanced our understanding of how this process works and have provided significant corroboration for Darwin's theory.
3. The evidence that Darwin collected during the five-year voyage of the HMS Beagle led to his theory that species adapt to different environments and change over time. At the time most people believed that all plant and animal species on Earth had been created and were fixed in form, but evidence convinced Darwin otherwise. Among the many species he observed were ostrich-like rheas that differed in form as he made his way up the coast of South America, and Galapagos tortoises that were adapted to life on individual islands. Darwin came to realize that these different species had originated from a common ancestor and adapted to their local environments over time.
4. Darwin developed his theory of natural selection after years of rigorous observation, testing, and analysis. Scientific theories develop as scientists collect evidence about the natural world, form hypotheses that explain what they've observed, use their hypotheses to make predictions, test these predictions with further observations and/or experiments, and generate explanations that survive the testing process. Aware that his ideas would shake the world, Darwin spent four decades at Down House, his rural retreat outside London, testing and strengthening his theory.
5. All life, including humans, evolved from a common ancestor through the process of natural selection. Over the course of biological evolution, populations branch off from one another, stop interbreeding, and become separate species. These species continue to adapt and change over time. Darwin called this process "descent with modification," and grounded it in the evidence that all organisms differ among themselves (variation), pass traits on to their offspring (inheritance), some of which, being better adapted, survive and reproduce (selection), and that periods of time are involved.
6. Modern evidence supports and expands upon Darwin's theories. Genetic sequences, in combination with morphological studies of organisms, are used to construct evolutionary family trees that illustrate the relationships between diverse species, and provide very strong support for common ancestry.
7. Modern biology, and society in general, benefit from our understanding of the process of natural selection. Numerous scientists investigating the natural world today—whether fighting viruses, decoding DNA, or analyzing the fossil record—have found Darwin's theory of natural selection essential to their work. For example, scientists studying flu viruses can anticipate which new varieties might evolve to become most harmful in the near future. They can then create vaccines designed to help the body's immune system ward off most of the upcoming year's varieties, a process that has saved countless lives.