「先有雞，還是先有蛋」這個問題爭論了好幾個世紀。 一個由進化遺傳學家、科學哲學家以及蛋農組成的研究隊伍，在去年作出「先有蛋，才有雞」的結論。
研究隊伍指出在史前時候，第一隻由鳥類變成的雞，成形之前也一定是蛋。 英國 University of Nottingham 的遺傳學專家 John Brookfield 指出，基因物質是不會改變的。 動物基因如果發生轉變，這個轉變也只能在胚胎階段發生。 雞是由蛋孵化而成，這就是說，必須先有蛋，才能有雞。
倫敦大學的科學哲學家 David Papineau 也有相同結論，「即使舊有觀念認為雞是由另一種禽鳥類進化而成，但是世界上第一隻雞出現前，牠的前身也一定先是蛋。 有些人會爭辯，如果蛋的父母不是雞？ 我會這樣反駁：即使一隻袋鼠生了一隻蛋，而這隻蛋孵化出來後卻原來是一隻鴕鳥，那麽，這隻蛋就是鴕鳥蛋，而不應叫做袋鼠蛋。 所以，如果蛋孵化出來後的是雞，這就是雞蛋，不用再置疑。」
從前「先有雞，才有蛋」的理論，是針對物種是由進化而成，而雞就是由一種出現於公元前二千年，生長在印度峽谷中的「原雞」所進化（達爾文《動物和植物在家養下的變異》）。 而在一八四四年蘇格蘭作家 Robert Chambers 所著的《自然歷史的創造遺跡》（Vestiges of the Natural History of Creation）也曾提出，現存所有物種都是從早期不同形態和結構變形而成。 變的理由是為了適應習性、環境和氣候等。
英國這批已成「eggsperts」的研究專家，也不否定物種由進化而成，但他們堅持，無論雞由哪種鳥類進化，第一隻雞確定是由蛋孵化出來。 到此，長年爭辯的問題似乎有了答案。
Saturday, September 20, 2008
Tuesday, September 9, 2008
the digital war on poverty
The digital divide（數碼鴻溝）is beginning to close. The flow of digital information（數字訊息的流動）-- through mobile phones, text messaging, and the Internet（手機 / 短訊 / 互聯網）-- is now reaching the world's masses, even in the poorest countries, bringing with it a revolution in economics, politics, and society.
Extreme poverty is almost synonymous with extreme isolation, especially rural isolation. But mobile phones and wireless Internet end isolation, and will therefore prove to be the most transformative technology of economic development of our time.
The digital divide is ending not through a burst of civic responsibility, but mainly through market forces. Mobile phone technology is so powerful, and costs so little per unit of data transmission, that it has proved possible to sell mobile phone access to the poor. There are now more than 3.3 billion subscribers in the world, roughly one for every two people on the planet.
......
Education will be similarly transformed. Throughout the world, schools at all levels wil go global, joining together in worldwide digital education networks（全球數字教育網絡）. Children in the United States will learn about Africa, China, and India not only from books and videos, but also through direct links across classrooms in different parts of the world. Students will share ideas through live chats, shared curricula, joint projects, and videos, photos, and text sent over the digital network.
Universities, too, will have global classes, with students joining lectures, discussion groups, and research teams from a dozen or more universities at a time. This past year, my own university -- Columbia University in New York City -- teamed up with universities in Ecuador, Nigeria, the United Kingdom, France, Ethiopia, Malaysia, India, Canada, Singapore, and China in a "Global Classroom" that simultaneously connected hundreds of students on more than a dozen campuses in an exciting course on global sustainable development.
In my book The End of Poverty, I wrote that extreme poverty can be ended by the year 2025. a rash predication, perhaps, given global violence, climate change, and threats to food, energy, and water supplies. But digital information technologies（數碼訊息技術）, if deployed cooperatively and globally, will be our most important new tools, because they will enable us to join together globally in markets, social networks, and cooperative efforts to solve our common problems.
（Jeffrey Sachs）
Extreme poverty is almost synonymous with extreme isolation, especially rural isolation. But mobile phones and wireless Internet end isolation, and will therefore prove to be the most transformative technology of economic development of our time.
The digital divide is ending not through a burst of civic responsibility, but mainly through market forces. Mobile phone technology is so powerful, and costs so little per unit of data transmission, that it has proved possible to sell mobile phone access to the poor. There are now more than 3.3 billion subscribers in the world, roughly one for every two people on the planet.
......
Education will be similarly transformed. Throughout the world, schools at all levels wil go global, joining together in worldwide digital education networks（全球數字教育網絡）. Children in the United States will learn about Africa, China, and India not only from books and videos, but also through direct links across classrooms in different parts of the world. Students will share ideas through live chats, shared curricula, joint projects, and videos, photos, and text sent over the digital network.
Universities, too, will have global classes, with students joining lectures, discussion groups, and research teams from a dozen or more universities at a time. This past year, my own university -- Columbia University in New York City -- teamed up with universities in Ecuador, Nigeria, the United Kingdom, France, Ethiopia, Malaysia, India, Canada, Singapore, and China in a "Global Classroom" that simultaneously connected hundreds of students on more than a dozen campuses in an exciting course on global sustainable development.
In my book The End of Poverty, I wrote that extreme poverty can be ended by the year 2025. a rash predication, perhaps, given global violence, climate change, and threats to food, energy, and water supplies. But digital information technologies（數碼訊息技術）, if deployed cooperatively and globally, will be our most important new tools, because they will enable us to join together globally in markets, social networks, and cooperative efforts to solve our common problems.
（Jeffrey Sachs）
Saturday, September 6, 2008
large hadron collider
The Large Hadron Collider, a massive particle detector, in its cavern below France.
Cern physicists believe they are close to crucial discoveries about the universe.FOR TOO MANY, SCIENCE IS AN INTELLECTUAL BLACK HOLE
The commissioning of the world's greatest atom smasher next week ought to be a cause for celebration. The giant US$8 billion Large Hadron Collider（大型強子對撞器）, much delayed and way over-budget, promises to unlock the most fundamental secrets of the universe, such as what gives matter its mass（質量的來由是甚麽？）, how gravity emerges and why so-called dark matter pervades the universe. If everything works as planned, humankind will reach a much deeper understanding of why the universe is the way it is（宇宙的起源為何？）.
Yet the experiment has been greeted with anxiety in many quarters. Scientists who work on the 20-nation project have received death threats. In the US and Europe, lawsuits have been filed against CERN（核子研究中心）, the European centre for particle physics that is running the collider, to stop it commissioning the collider.
The reason for the anxiety is that by colliding beams of particles called protons（超級粒子撞擊實驗）, the giant underground machine on the French-Swiss border will create "big bang" conditions similar to the dawn of the unuverse.
This means tiny black holes may be created. After repeat studies, scientists conclude the holes will disappear almost as soon as they appear, but some people around the world are not convinced. Many are worried there is a very slight but real chance the black holes will suck in the entire world.
In fact, no amount of scientific study can assure an increasingly sceptical public. Modern science and its many triumphs inspire unrealistic hopes and fears. Its language is mathematics, which is complex and difficult to understand, and many busy scientists do not bother to explain their work. Their research is often expensive but without immediate benefits. Genetically modified food has been described as Frankenfood; some people worry nanotechnology will create tiny self-replicating robots and turn the Earth into grey goo.
The fuss about the collider shows a gulf still separates the public from the scientific elite. Scientists, especially those who are publicly funded, need to do a better job of explaining their work. Without proper public understanding and support, they cannot hope to advance the cause and the frontiers of science.
The commissioning of the world's greatest atom smasher next week ought to be a cause for celebration. The giant US$8 billion Large Hadron Collider（大型強子對撞器）, much delayed and way over-budget, promises to unlock the most fundamental secrets of the universe, such as what gives matter its mass（質量的來由是甚麽？）, how gravity emerges and why so-called dark matter pervades the universe. If everything works as planned, humankind will reach a much deeper understanding of why the universe is the way it is（宇宙的起源為何？）.
Yet the experiment has been greeted with anxiety in many quarters. Scientists who work on the 20-nation project have received death threats. In the US and Europe, lawsuits have been filed against CERN（核子研究中心）, the European centre for particle physics that is running the collider, to stop it commissioning the collider.
The reason for the anxiety is that by colliding beams of particles called protons（超級粒子撞擊實驗）, the giant underground machine on the French-Swiss border will create "big bang" conditions similar to the dawn of the unuverse.
This means tiny black holes may be created. After repeat studies, scientists conclude the holes will disappear almost as soon as they appear, but some people around the world are not convinced. Many are worried there is a very slight but real chance the black holes will suck in the entire world.
In fact, no amount of scientific study can assure an increasingly sceptical public. Modern science and its many triumphs inspire unrealistic hopes and fears. Its language is mathematics, which is complex and difficult to understand, and many busy scientists do not bother to explain their work. Their research is often expensive but without immediate benefits. Genetically modified food has been described as Frankenfood; some people worry nanotechnology will create tiny self-replicating robots and turn the Earth into grey goo.
The fuss about the collider shows a gulf still separates the public from the scientific elite. Scientists, especially those who are publicly funded, need to do a better job of explaining their work. Without proper public understanding and support, they cannot hope to advance the cause and the frontiers of science.
schools warned
SCHOOLS WARNED TO BE AWARE OF GLOBAL CHANGES
Schools in richer countries must take account of major international developments such as changing climate and lifestyles, family structures, migration, ageing populations and the rise of Asia if they are to adequately prepare the next generation for the future, the Paris-based OECD says.
The Organisation for Economic Co-operation and Development's "Trends Shaping Education" report suggests a raft of issues educationalists must consider in devising school systems that respond to the future.
These include economic issues that impact lifestyles, such as energy consumption, growing affluence, ageing populations, as well as the role of the welfare state, and changing values as we face globalisation and other challenges.
"We believe it is extremely important to have a long-term vision on education because it is shaping people who will be working in jobs in 20 years time," said Henno Theisens, one of the report's authors.
"If countries do not reflect on longer-term trends they will give children far less preparation for the world. Head teachers from most countries in the world should be able to understand major global. economic and societal trends, and make use of them in designing curricula."
The report suggests that the growing role of Asian countries might require changes in curricula, not just for language teaching such as the rise of Mandarin but also history, geography and other subjects.
"Education and training systems have traditionally been strong bastions of national decision-making, are they sufficiently sensitive to international developments?" the report asks.
Clear trends are already emerging that are changing, or have the potential to radically changes, the world as schoolchildren become adults.
For example, issues like global warming and migration to cities has implications for where new schools should be built.
Changes in social behaviour, including more working women, mean that schools will have to provide more "out of school" services and act as a "social anchor" for urbanising populations that experience isolation and exclusion in the city, Dr Theisens said.
The report asks if schools should be involved in changing behaviour that endangers the environment.
(Yojana Sharma)
Schools in richer countries must take account of major international developments such as changing climate and lifestyles, family structures, migration, ageing populations and the rise of Asia if they are to adequately prepare the next generation for the future, the Paris-based OECD says.
The Organisation for Economic Co-operation and Development's "Trends Shaping Education" report suggests a raft of issues educationalists must consider in devising school systems that respond to the future.
These include economic issues that impact lifestyles, such as energy consumption, growing affluence, ageing populations, as well as the role of the welfare state, and changing values as we face globalisation and other challenges.
"We believe it is extremely important to have a long-term vision on education because it is shaping people who will be working in jobs in 20 years time," said Henno Theisens, one of the report's authors.
"If countries do not reflect on longer-term trends they will give children far less preparation for the world. Head teachers from most countries in the world should be able to understand major global. economic and societal trends, and make use of them in designing curricula."
The report suggests that the growing role of Asian countries might require changes in curricula, not just for language teaching such as the rise of Mandarin but also history, geography and other subjects.
"Education and training systems have traditionally been strong bastions of national decision-making, are they sufficiently sensitive to international developments?" the report asks.
Clear trends are already emerging that are changing, or have the potential to radically changes, the world as schoolchildren become adults.
For example, issues like global warming and migration to cities has implications for where new schools should be built.
Changes in social behaviour, including more working women, mean that schools will have to provide more "out of school" services and act as a "social anchor" for urbanising populations that experience isolation and exclusion in the city, Dr Theisens said.
The report asks if schools should be involved in changing behaviour that endangers the environment.
(Yojana Sharma)
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