Ishango bone The Ishango bone is a bone tool, dated to the Upper Paleolithic era. It is a dark brown length of bone, the fibula of a baboon,[1] with a sharp piece of quartz affixed to one end, perhaps for engraving. It was first thought to be a tally stick, as it has a series of what has been interpreted as tally marks carved in three columns running the length of the tool, but some scientists have suggested that the groupings of notches indicate a mathematical understanding that goes beyond counting. It has also been suggested that the scratches might have been to create a better grip on the handle or for some other non-mathematical reason.[2] The Ishango bone was found in 1960 by Belgian Jean de Heinzelin de Braucourt while exploring what was then the Belgian Congo.[3] It was discovered in the African area of Ishango, which was centered near the headwaters of the Nile River at Lake Edward (now on the border between modern-day Uganda and Congo). Possible meaning[edit] Mathematical calculations[edit]
Time Travel and Modern Physics First published Thu Feb 17, 2000; substantive revision Wed Dec 23, 2009 Time travel has been a staple of science fiction. With the advent of general relativity it has been entertained by serious physicists. But, especially in the philosophy literature, there have been arguments that time travel is inherently paradoxical. The most famous paradox is the grandfather paradox: you travel back in time and kill your grandfather, thereby preventing your own existence. To avoid inconsistency some circumstance will have to occur which makes you fail in this attempt to kill your grandfather. 1. You are very depressed. 2. The standard worry about time travel is that it allows one to go back and kill one's younger self and thereby create paradox. Well, one worry is the question as to why such schemes always fail. 3. Imagine the following set-up. However, it does not take much thought to realize that there is no paradox here. Let us now be more general and allow color photography. Figure 1 Figure 2 4.
70 Things Every Computer Geek Should Know. | Arrow Webzine The term ‘geek’, once used to label a circus freak, has morphed in meaning over the years. What was once an unusual profession transferred into a word indicating social awkwardness. As time has gone on, the word has yet again morphed to indicate a new type of individual: someone who is obsessive over one (or more) particular subjects, whether it be science, photography, electronics, computers, media, or any other field. A geek is one who isn’t satisfied knowing only the surface facts, but instead has a visceral desire to learn everything possible about a particular subject. How to become a real computer Geek? Little known to most, there are many benefits to being a computer geek. You may get the answer here: The Meaning of Technical Acronyms 1. One of the best list of default passwords. 1A. 2. If you rolled your eyes here, that is a good thing. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21.
Infographic of the Day: How the Global Food Market Starves the Poor To understand the complexities of the international food market--and how traders in Chicago can cause Africans to starve--you could get a ph.D. in economics, or read a 400-page report from the World Bank. Or you watch this superb nine minute video, directed by Denis van Waerebeke. Though ostensibly created for a science show in Paris for 12 year olds, it's actually probably waaaay over a kid's head. Just watch--it's excellent, and very well illustrated: The video begins with a basic question: How is it that the first world has an oversupply of food, while 1 in 7 in the world go malnourished? That can have disastrous effects. The solutions will involve everyone, the world over. Still hungry for more infographics videos? [Via Infosthetics]
Adam and Eve: Adam's rib count. Claim CB381: As related in Genesis 2, Eve was created from one of Adam's ribs. As a consequence, men have one fewer set of ribs than women do. Source: reported by Root-Bernstein, 1995. (see below) Response: Men and women have the same number of ribs. References: Gilbert, Scott F. and Ziony Zevit. 2001. Further Reading: The concerns of a mouse… A mouse looked through the crack in the wall to see the farmer and his wife open a package. “What food might this contain?” The mouse wondered. He was devastated to discover it was a mousetrap. Retreating to the farmyard, the mouse proclaimed this warning : “There is a mousetrap in the house! The chicken clucked and scratched, raised her head and said, “Mr. The mouse turned to the pig and told him, “There is a mousetrap in the house! The pig sympathized, but said, “I am so very sorry, Mr. The mouse turned to the cow and said, “There is a mousetrap in the house! The cow said, “Wow, Mr. So, the mouse returned to the house, head down and dejected, to face the farmer’s mousetrap. … Alone That very night a sound was heard throughout the house – the sound of a mousetrap catching its prey. The farmer’s wife rushed to see what was caught. In the darkness, she did not see it. It was a venomous snake whose tail was caught in the trap. The snake bit the farmer’s wife. The farmer rushed her to the hospital.
Ancient Hunter-Gatherers Kept in Touch Until about 8500 years ago, Europe was populated by nomadic hunter-gatherers who hunted, fished, and ate wild plants. Then, the farming way of life swept into the continent from its origins in the Near East, including modern-day Turkey. Within 3000 years most of the hunter-gatherers had disappeared. Little is known about these early Europeans. But a new genetic analysis of two 8000-year-old skeletons from Spain suggests that they might have been a remarkably cohesive population both genetically and culturally—a conclusion that other researchers find intriguing but possibly premature. The first modern human hunter-gatherers occupied Europe at least 40,000 years ago. Yet, while researchers have intensively studied the ancient farmers who followed them, relatively little is known about Europe's Mesolithic people. The team was able to extract mitochondrial DNA (mtDNA) from both sets of remains, and to completely sequence the mtDNA from the La Braña 1 skeleton.
Table of contents (With last update date) Cover Foreword (August 13, 2009) Part 1. Preface to part 1 (April 12, 2000) Chapter 1. 1.1. 1.6. 1.7. Chapter 2. 2.1. 2.2. 2.3. 2.4. 2.5. 2.6. Chapter 3. 3.1. 3.2. 3.3. 3.4. Chapter 4. 4.1. 4.2. 4.3. 4.4. Chapter 5. 5.1. 5.2. 5.3. 5.4. 5.5. 5.6. 5.7. 5.8. 5.9. 5.10. 5.11. 5.12. 5.13. 5.14. 5.15. 5.16. Chapter 6. 6.1. 6.2. 6.3. 6.4. 6.5. 6.6. 6.7. 6.8. 6.9. 6.10. 6.12. Part 2. Preface to part 2 (October 17, 2010) Chapter 7. 7.1. 7.2. 7.3. 7.4. 7.5. 7.6. 7.7. 7.9. 7.10. Chapter 8. 8.1. 8.2. Chapter 9. 9.1. 9.2. 9.3. 9.4. 9.6. Chapter 10. 10.1. 10.2. 10.3. 10.4. Chapter 11. 11.1. 11.2. 11.3. 11.4. 11.5. 11.6. 11.7.The victim/victimizer polar pair 11.8. 11.9. 11.10. Chapter 12. 12.1. 12.2. 12.3. 12.5. 12.6. 12.7. Chapter 13. 13.1. 13.2. 13.3. 13.4. 13.5. 13.6. 13.7. 13.8. 13.9. 13.10. 13.11. 13.12. 13.13. Chapter 14. 14.1. 14.2. 14.3. 14.4. 14.5. 14.6. 14.7. 14.8. Chapter 15. Chapter 16. 16.3. 16.4. 16.5. Part 3. Preface to part 3 (November 18, 2009) Chapter 17. 17.1.
Human Ancestor May Put Twist in Origin Story Known as the ancient human ancestor was discovered in the Malapa region of South Africa in 2008 and was described for the first time last April. (See "'Key' Human Ancestor Found: Fossils Link Apes, First Humans?" ) Now a suite of five studies, published in this week's issue of the journal is delving deeper into the species' unusual mix of human and apelike traits to help refine s place in the time line of human evolution . After examining s anatomy, for instance, scientists think they may have evidence that the species was capable of making and using tools. In addition, the team thinks it may have found samples of fossilized skin. "We've started an open-access experiment"—called the Malapa Soft Tissue Project —"to determine if we do in fact have skin," said study leader Lee Berger , an anthropologist at the University of the Witwatersrand in Johannesburg. "We are enlisting the entire scientific community in exploring this possibility." (See pictures of the fossils .)
The Socratic Method The Socratic Method:Teaching by Asking Instead of by Tellingby Rick Garlikov The following is a transcript of a teaching experiment, using the Socratic method, with a regular third grade class in a suburban elementary school. I present my perspective and views on the session, and on the Socratic method as a teaching tool, following the transcript. The class was conducted on a Friday afternoon beginning at 1:30, late in May, with about two weeks left in the school year. This time was purposely chosen as one of the most difficult times to entice and hold these children's concentration about a somewhat complex intellectual matter. The experiment was to see whether I could teach these students binary arithmetic (arithmetic using only two numbers, 0 and 1) only by asking them questions. I had one prior relationship with this class. "But what I am really here for today is to try an experiment with you. 1) "How many is this?" 2) "Who can write that on the board?" 4) Another way? 5) Another way?
10 Transitional Ancestors of Human Evolution Humans The evolution from our closest non-human ancestor to present day humans is one with many transitions. Some of these transitions are widely agreed upon by the scientific community while others are shrouded in frustrating darkness. Below are the ten species that have added the most to our lineage, some adding seemingly simple advances like walking on two legs and chewing food differently to mastering fire and dominating every other species on Earth. Sahelanthropus tchadensis 6-7 mya The beginnings of our lineage away from the Great Apes really start with the separation from chimpanzees, our closest non-hominin relative. Kenyanthropus platyops 3.5 mya Found at Lake Turkana, Kenya in 1999, K. platyops changed the way paleoanthropologists viewed our ancestral tree. Australopithecus afarensis 3.0-3.9 mya In 1974 at Hadar, Ethiopia researchers discovered about 40% of a skeleton came to be known as “Lucy.” Paranthropus boisei 1.4-2.3 mya Homo habilis 1.6-2.5 mya Homo ergaster 1.5-1.8 mya Homo erectus
How Communism Works" "<img src=" width="828" alt="mural of Marx, Engels, Lenin" border="0">" In a perfect world, everyone would have food and shelter, and a true utopian society would be devoid of sexism, racism and other forms of oppression. But for most of the world's population, this perfect society isn't possible. Communism is one proposed solution to these problems. Most people know what communism is at its most basic level. According to the philosopher Frederich Engels' "Principles of Communism," the plan for ultimate financial and social equality is built on the principle that the system should spread around the world until all countries are on board [source: Engels].
Why crying babies are so hard to ignore Ever wondered why it is so difficult to ignore the sound of a crying baby when you are trapped aboard a train or aeroplane? Scientists have found that our brains are hard-wired to respond strongly to the sound, making us more attentive and priming our bodies to help whenever we hear it – even if we're not the baby's parents. "The sound of a baby cry captures your attention in a way that few other sounds in the environment generally do," said Katie Young of the University of Oxford, who led the study looking at how the brain processes a baby's cries. She scanned the brains of 28 people while they listened to the sound of babies and adults crying and sounds of animal distress including cats meowing and dogs whining. Using a very fast scanning technique, called magnetoencephalography, Young found an early burst of activity in the brain in response to the sound of a baby cry, followed by an intense reaction after about 100 milliseconds.