This showed that greenfinch and starling numbers were continuing to decline, but reaffirmed the success of the house sparrow, which topped the Welsh and UK surveys.
Alfred Wegener (1880 - 1930). Alfred Wegener proposed the theory of continental drift at the beginning of the 20th century. His idea was that the Earth's continents were once joined together, but gradually moved apart over millions of years.his slideshow explains Wegener's theory. Earth around 200 million years ago, at the time of Pangaea. Wegenerâs evidence for continental drift was that: 1  the same types of fossilised animals and plants are found in South America and Africa.
Continental drift takes place because continents sit on crustal plates which float on the Earth's magma, and the magma has convection currents in it which push against the plates and cause them to move, slowly but inexorably.