Perhaps one of the finest examples of evolution in action were the finches of the Galapagos Islands. Each island had a different species of finch, and each species of finch had a different sized beak. The finches with the largest beak lived on an island with plenty of hard nuts, while the smallest-beaked finch lived on an island where the main food source was insects. This showed how well these birds had adapted to their environment.
The appearance of modern man about 100,000 years ago was marked by a decrease in body size at the same time as an increase in brain size. However, it is worth noting that Neanderthals, which became extinct about 40,000 years ago, had larger brains than modern Homo sapiens.
The ionosphere is an abundant layer of electrons and ionized atoms and molecules that stretches from about 48 kilometers (30 miles) above the surface of the Earth to the edge of space at about 965 km (600 mi). This dynamic region grows and shrinks based on solar conditions. Because of its high concentration of ions and free electrons, this region is able to reflect radio waves and makes radio communications possible.
Because Einstein's general theory of relativity was considered too controversial, he was awarded the Nobel Prize in Physics "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect."