Five years ago, a Chinese lawyer bought an old map from a dealer in Shanghai. Today, that map is at the center of the debate over who came to America and when.
The Chinese map, dated 1763, shows North and South America in a fair amount of detail. No surprise there. However, an inscription on the map says it is a copy of an earlier map, from 1418. If correct, that means the Chinese visited America more than 70 years before Columbus.
Historians have long known that Chinese Admiral Zheng He sailed all over Asia in the 1400s, and even got as far as the east cost of Africa. However, most doubt he ever reached the Americas—let alone explored them in the amount of detail this map suggests.
The map is currently being tested to see if it really is as old as it says it is. But even if the tests come back positive, the debate will not be settled. Even if the map is authentic, it is still only a copy—drawn in 1763, and supposedly based on an older map which no one has ever seen. It could just as easily be based on a map from, oh, 1762.
(One interesting feature the article does not dwell on is the fact that the map also shows Australia—small and not in the right place, but it's there. Australia was not visited by outsiders until 1770. If the map really does date from 1763, then it may have a lot more to say about the history of Australia than the history of America.)
Tags : Scientists have long known that the giant, four-legged sauropods-—like the Science Museum's Diplodocus-—evolved from earlier, two-legged species. But exactly how has been a mystery. A scientist at the Smithsonian thinks he's found the answer.
Dr. Hans Sues has studied eggs and babies of the two-legged dinosaur Massospondylus (MASS-oh-SPON-dih-lus). The fossils showed that babies walked on all four legs, and switched to the two-legged adult gait at age two or three years. Sues suggests that later species retained the juvenile feature, and stayed on four legs their entire lives. This evolutionary process is called neotony.
Not everyone is convinced, though. The Science Museum's Kristi Curry Rogers, a world expert on sauropods, thinks Massospondylus was not an ancestor to the later giants.
(Neotony—the process of retaining juvenile traits into adulthood—is a well-documented evolutionary phenomenon. In fact, it may have occurred in humans! Adult humans have many traits that are found in young apes, but disappear as the animal grows up—things like a flat face, little hair, large head, and a neck directly beneath the skull rather than behind it. Some scientists believe that, as out species evolved away from the apes, we developed more slowly, so that adult humans retain these features, while adult apes outgrow them. In fact, Aldous Huxley once wrote a novel based on the premise that, if a person lived long enough, they eventually would develop into an ape! Pure fiction, but a fun idea!)
Scientists at the Max Plank Institute in Germany have discovered that living trees are a major source of methane in the Earth's atmosphere. Methane is a major "greenhouse gas," implicated in global warming.
Before this study, scientists thought plants only released small amounts of methane, and then only when they decomposed (as in swamps). The new research shows that plants release methane throughout their lives, and in large amounts—up to 30% or more of the planet's total methane production may come from plants.
This forces us to re-think environmental efforts. Strategies for dealing with climate change, such as the Kyoto Protocols, often call for planting more trees. And it's true that trees do take a lot of carbon dioxide out of the atmosphere—the most prevalent greenhouse gas. But now it turns out trees also release methane, so their benefit is not quite as great as once thought.
Fruit Fly - Drosophilidae: Drosophila melanogaster Photo by André Karwath
Human and mouse cells are continuously replenished with stem cells, and when they are not regulated correctly, common digestive diseases and cancer can occur. Insects had not been investigated until recently when adult fruit flies (Drosophila) were found to have the same stem cells controlling cell regulation in their gut as humans. This is reported by Benjamin Ohlstein and Allan Spradling at The Carnegie Institution of Washington, Maryland. The similarity in intestinal stem cells of the fruit fly includes their being multipotent, which means that the stem cells can turn into different cell types in both insects and humans. This research helps in developing cures for digestive disorders including some cancers, and indicates that insects and humans were derived from the same evolutionary pathway more than 500 million year ago.
Orion Nebula: Image courtesy NASA, ESA, M. Robberto (Space Telescope Science Institute/ESA) and the Hubble Space Telescope Orion Treasury Project Team
Orion Nebula 2: Image courtesy NASA, ESA, and The Hubble Heritage Team (STScI/AURA)
Personally, I think the Hubble Space Telescope is incredible — the images it captures fascinate me. These images of the Orion Nebula were just recently released, and if you're into images from space, or just think these are cool, visit the media site and look at the larger resolution and magnified images they have available there, as well as the detail images with description. The level of detail is amazing. Totally gets my imagination going. Here is the press release on the image as well.
The University of Witwatersrand in Johannesburg South Africa has long been known for its impressive discoveries related to human evolution. Discoveries from Witwatersrand related to human evolution typically emphasized the importance of not only Africa but South Africa in the development of early man. Many of the more famous discoveries related to Paleoanthropology or the study of human evolution come from East Africa — where researchers have discovered, and continue to discover, some of the best evidence for human origins in Africa. Researchers further south, however, continued to argue that fossil discoveries from South Africa should not be discounted from the developing picture of the history of early man.
Raymond Dart with Taung skull: Raymond Dart with Taung skull Credit
One of the most significant South African discoveries was the Taung child, which was discovered in 1924 and was given its name when the first researchers to examine the fossil concluded that the specimen was so small because it was a child. This week, researchers from Witwatersrand are announcing that the Taung child could have been killed by a large bird. Yahoo News is reporting that by studying the hunting abilities of modern eagles in West Africa, researchers determined what signs would be left behind on a skull of an animal that was killed by a predatory bird. Armed with this new knowledge, Physical Anthropologists reexamined the Taung child and found traces of cuts behind the eye sockets. Even though the specimen has surely been examined hundreds of times since its discovery, nobody had really noticed the marks before.
Discoveries like this one prove that new discoveries and interpretations can be made by simply reexamining old discoveries with a fresh pair of eyes. No pun intended.
Scientists in Maryland have put together a family tree for cats. Using DNA evidence, they found that the first cats evolved in South East Asia around 11 million years ago. The Panthera genus, which includes lions, tigers and jaguars, evolved first. Various other groups evolved rapidly, with the final group, the ancestor of the domestic house cat, emerging in Africa and Europe about 6.5 million years ago.
Confuse-a-cat: The evolutionary history of cats is quite a head-scratcher!
According to
this blogger, the interesting thing about this study is that it was done entirely by genetics — by comparing DNA samples. Species with similar DNA are considered to be close relatives. The more traditional way of figuring out evolutionary relationships — by studying fossils — was less helpful in this particular case. Cat fossils look very much alike, and it can be extremely difficult to figure out exactly which species is related to which. Especially in a family like the cats, where the different animals moved around a lot. (According to the study, the ancestors of the cheetah started in South East Asia, moved to North America, and then back to Asia / Africa!)
Just goes to show that evidence for evolution comes from many different sources.
* (Yes, it's another obscure reference to pop songs from Gene's formative years...)
The Food and Agriculture Organization of the United Nations says that the bird flu (Avian Influenza virus H5N1) may become endemic in the country of Turkey. Over the past week we have seen a growing number of human infections in Turkey and at least two Turkish deaths caused by the disease.
A disease is considered to be endemic when it does not require any outside inputs to continue in an area.
Endemic or not? An example
Chickenpox are endemic in Minnesota and the US because you can catch it without someone coming from outside that area and giving it to you. The same cannot be said for Malaria. You would have to come in contact with some outside carrier to catch Malaria in Minnesota.
The fear is that the disease may have infected enough birds to continue spreading around Turkey without any newly infected birds traveling from Asia where the disease started. Currently the disease cannot spread from human to human. To become infected with the virus you have to come in contact with an infected bird.
However, there is a concern that if the disease continues to spread in Turkey that it could become a problem in surrounding countries like Armenia, Azerbaijan, Georgia, Iraq, Iran and Syria.
The Buzz
Since early 2004 the scientific community has been all abuzz with news of the multiple remarkable discoveries of South Korean scientist Hwang Woo-suk. His work has given him rock-star status in South Korea that we can hardly imagine in America. The only problem is, he was completely lying about several of his key findings. He finally admitted to this deceit on Monday, Jan. 9th, but also claims he was sabotaged.
Hwang Woo-Suk: The scientist who fabricated stem cell research. Image credit
Hwang Woo-suk was a pioneer in the field of stem-cell research and cloning. Stem cells are the special cells in a human embryo that can grow into any type of tissue or organ in the body. Research into these cells offers the possibility of many unique science breakthroughs:
A goaltender: Diving for the ball.
I play soccer. I can frequently run and kick the ball without falling on my face, so I enjoy it. In fact, it is my most favorite sport to play. However, I think that watching soccer on TV is like watching paint dry — I find it to be very dull.
However, researchers at the Los Alamos National Laboratory have found that soccer is the most unpredictable sport, as it more likely that a team with a worse record can defeat a team with a better record. The researchers looked at the results of over 300,000 soccer, baseball, basketball, hockey and football games, and found that the likelihood for an upset was greatest in soccer.
So, it should be more exciting to watch a soccer game because the results are not as predicated on the records of the two teams as other sports.
This research is an interesting way to combine an interest in sports and an interest in math!
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