The magic of evolution
I was a kid likes to play with tadpoles, but has never been curious about why the process of growing tadpoles is so strange: the bulk of a tail slowly grow two hind legs, and then went on to grow two front legs, then to the tail disappeared color from black to green frogs, and even frogs do not need to live in the water, tadpoles version of 鲤鱼跳龙门 ah! More incredible is that why only crawl ugly caterpillar turn into colorful butterflies fly? Of course, the biology textbook told me that this is a biological metamorphosis. In vertebrates, mostly fish and amphibians such a magical function. However, as to why some biological metamorphosis, most organisms do not, it seems not entirely convincing reason to explain such strange things.
Recently read one of the "New Scientist" by the end of September, an interpretation of the biological metamorphosis and evolution of the article, which lists the recent research of some scientists, but also can be used as the metamorphosis hypothesis. In Darwin's era (the 1870s), Darwin's good friend Francis, the Maitland of Balfour was trying to find the larvae of the ancestors of all animals. Because the origin of life and the ocean, he naturally from marine organisms. The results, he found the same kind of marine life there are a wide variety of larvae, the larvae of the so-called ancestor of all animals may be a cilia-covered sphere. British scientist Donald Williamson, after 1950 also began a similar study results also found that the abnormal way of marine life amazing. Such as one called luidia sarsi of marine life, its larvae for women and children, translucent, eating seaweed for a living, but wait for it to grow to four centimeters, it is the body cavity of a cell population will grow their own as a new creature: a meat and like to stay in the dark bottom of the sea starfish class biological
, Donald Williamson, was raised a staggering theory: why there is a biological metamorphosis looks like an organism into another organism? There are a number of different ancestors of this creature! In other words, the hybridization of the ancestors of these organisms produce these creatures, so the development process of these organisms to maintain the characteristics of different ancestors! 2002, scientists from the hybridization of marine organisms and found that larvae of hybrid offspring is the last evolution has become a round into the body, and these adults are very similar to the larvae of the common ancestor of all animals previously speculated by Francis the Maitland of Balfour. Modern biotechnology, especially genetic analysis also confirmed a similar hybrid bio-integration of the characteristics of both parents, opened a new way of evolution! What does this show? Donald Williamson is the point of view: the hybrid one of the ways of evolution.
Of course, modern science is not in favor of the hybrid test, animals contrary to the ethics of such technology. However, starting from the existing body of scientific evidence that such evidence can confirm that the impact of hybridization in evolution.
Way, the point of view of the Big Bang is popular, in particular, Hawking's A Brief History of Time "is so popular, combined with this year's Nobel Prize in Physics is to give the universe to accelerate the expansion of discoverers. The big bang theory probably means that the universe was formed by the explosion of a singularity. That is, all are at that moment became possible. Of course, the long process of cosmic evolution pole. In fact, in biological evolution, there is a small, similar to the Big Bang process, this is the "Cambrian explosion".
According to the Chinese on the wiki to explain the Cambrian explosion refers to the Cambrian period dating back 530 million years ago, just 200 years, the case of the leaps and bounds in the evolution of life. Almost all modern animal "door during this period. fossils found around the world confirms the spectacular history of this evolution of life, such as found in Chengjiang County, Yunnan Province, China, the fossils of this period typically presents during this period very many different types of organisms. "Darwin himself for the Cambrian explosion is very confused, even today, the Cambrian explosion is still one of the major puzzles of the scientific community. However, scholars have proposed several hypotheses, for example, that the earth after the Cambrian appear stable enough to save the fossil rock, sediments of the Precambrian destroyed in the geothermal and pressure can not form a fossil. It was also considered that period the climate is particularly good, making the accumulated a sufficient amount of oxygen in the atmosphere, enough to make short-term evolution of large numbers of animals.
Then Williamson's hybridization theory naturally assume that a. Biological prosperity in that period, perhaps a hybrid between different organisms. However, obviously, Williamson, this doctrine is not very popular, but as a science, should not we be bold hypothesis, A careful, at least in the existing test, the doctrine has found some evidence.
Then again, is not abnormal biological hybrid ancestors? I have seen a nonsense article, it says that human save the ability of the fish (swimming), and can live on land, indicating that human evolution in fact, incomplete, or have many ancestors. Of course, but fortunately we human embryos is not abnormal development. But think about it very scary to give birth to some strange offspring in case the hybrid is also a means of evolution, humans eventually will not hybridization with other populations in order to survive? The horror movie "Alien" perhaps on the self-fulfilling prophecy. . .
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New Scientist article original address (30 September 2011 by Frank Ryan) at: http://www.newscientist.com/article/mg21128312.100-metamorphosis-evolutions-freak-factory.html
