Wolves, dogs and humans

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Week 3

There is no doubt that dogs are the oldest of all species tamed by humans and their domestication was based on a mutually beneficial relationship with man. The conventional view is that the domestication of wolves began between 10,000 and 20,000 years ago. However, a recent ground-breaking paper by a group of international geneticists has pushed this date back by a factor of 10. Led by Dr. Robert Wayne, at the University of California, Los Angeles, the team showed the all dog breeds had only one ancestor, the wolf. They did this by analyzing the genetic history through the DNA of 162 wolves from around the world and 140 domestic dogs representing 67 breeds. The research also confirms, for the first time, that dogs are descended only from wolves and do not share DNA with coyotes or jackals. The fact that our companionship with dogs now appears to go back at lest 100,000 years means that this partnership may have played an important part in the development of human hunting techniques that developed to 90.000 years ago It also may even have affected the brain development in both species.
The Australian veterinarian David Paxton suggest that in the period of first contact, people did not so much domesticate wolves as wolves domesticated people. Wolves may have started living at the edge of human settlements as scavengers, eating scraps of food and waste. Some learned to live with human beings in a mutually helpful way and gradually evolved into dogs. At the very least, they would have protected human settlement, and given warnings by barking at anything approaching. The wolves that evolved into dogs have been enormously successful in evolutionary terms. They are found everywhere in the inhabited world, hundreds of millions of them. The descendants of the wolves that remained wolves are now sparsely distributed, often in endangered populations.
In return for companionship and food, the early ancestor of the dog assisted humans in tracking, hunting, guarding and a variety of other activities. Eventually humans began to selectively breed-these animals for specific traits. Physical characteristics changed and individual breeds began to take shape. As humans wandered across Asia and Europe, they took their dogs along, using them for additional tasks and further breeding them for selected qualities that would better enable them to perform specific duties.
According to Dr. Colin Groves, of the Department of Archaeology and Anthropology at Australian Nation University, early humans came to rely on dogs’ keen ability to hear, smell and see-allowing certain areas of the human brain to shrink in size relative to other areas. ‘Dogs acted as humans’ alarm systems, trackers and hunting aids, garbage disposal facilities, hot-water bottles and children’s guardians and playmate. Humans provided dogs with foods and security. This symbiotic relationship was stable for over 100,000 years and intensified into mutual domestication,’ said Dr. Groves. In his opinion, humans domesticated dogs and dogs domesticated humans.
Dr. Groves repeated an assertion made as early as 1914- that humans have some of the same physical characteristics as domesticated animals, the most notable being decreased brain size. The horse experienced a 16 percent reduction in brain size after domestication while pigs brains shrank by as much as 34 per cent. The estimated brain-size reduction in domesticated dogs varies from 30 percent to 10 per cent. Only in the last decade have archaeologists uncovered enough fossil evidence to establish that brain capacity in humans declined in Europe and Africa by at least 10 per cent beginning about 10,000 years ago. Dr. Groves believes this reduction may have taken place as the relationship between humans and dogs intensified. The close interaction between the two species allow for the diminishing of certain human brain functions like smell and hearing

Passage 2

Crop circles
The crop circ
Le phenomenon has puzzled and mystified humanity for many years. The designs just appear, placed carefully in fields of food grains. Some are larger than football fields and highly complex in design and construction. Others are smaller and more primitive. We call them crop circles, but many of them are not circular. Some are elongated abstract designs, a few resemble insects or other known forms, and some are mixtures of lines, circles, and other shapes melded into intricate patterns. Most become visible overnight, though it has been claimed that a few have appeared within a half-hour in broad daylight.
Crop circles have appeared all over the world. About 10,000 instances from various countries have been reported in recent years. The first modern rash of crop circles appeared in Australia in December of 1973. A strange circular imprint appeared in a wheat field near Wokurna, a community southeast of Adelaide. Soon seven swirled circles up to 14 feet in diameter appeared in an oatfield nearby. In December of 1989, an amazing set of circles, ranging from a few inches to a few feet in diameter appeared in the wheat belt west of Melbourne. As many as 90 crop circles were found. The best documented and largest modern spread of crop circles began in southern England during the summer of 1980. By the end of 1988. 112 new circles had been formed. At that time circles were being reported worldwide, 305 by the end of 1989. The total grew to an outstanding 1000 newly-formed circles in 1990. In 1991, 200 to 300 circles were reported. Crop circles have been documented in over 30 countries, including Canada, the former Soviet Union, Japan and the United States.
Nine out of ten circles remained simple with broken stems flattened to the ground and swirled. The stalks around the circles remained completely erect. But over the years, crop circles have become much more geometrically intricate. Patterns involved multiple circles, bars, triangles, rings, and spurs. Pictorial imagery also appeared. Reliable eyewitnesses have reported seeing unusual lights and hearing unidentifiable sounds while on an early-morning walk in the countryside where a crop circles showed later that day. High-pitched, warbling noises have been recorded at the site of some crop circles. On several occasions a strange glow or a darker colouring has been seen in the sky over a crop circle. And in more than one instance, the electrical power of small planes flying overhead has been cut off abruptly. While the causal energies do not seem to harm animals, or ever insects as far as we can tell, will creatures tend to avoid the circles. Flocks of birds have been seen to split apart and fly around the perimeter rather than go directly over crop circle formation.

Researchers have spent a great deal of time investigating different aspects of crop circles. They try to detect traces of human involvement in the circle-making, test the area of the circle itself for geophysical anomalies, and analyze the field’s grain both from within and outside the circles, searching for differences.

Dr. W.C. Levengood of BLT Research in Cambridge, Massachusetts, has analyzed many grain samples and confirmed, time after time, significant changes at the cellular level of crop circle plants. The plants from the circles have elongated cells and blown-out growth nodes. Seeds from the circle plants often show accelerated growth rates when they are sown, and in some instances, quite different-looking plants result. In many instances it appears that a vortex-like energy causes the plants to swirl down, flattening the design into the land. Whatever this energy is, it does not generally inhibit the plants’ growth. They continue to show normal response to the sun, rising upward over several days following the appearance of the circle. Michael Cohorts of Duke University found occasions of short-lived radio nuclides in the top layer of soil in the some of the formation. A British government laboratory found diminished nitrogen and decreased nematode populations as well as decreased water content in the soil of a formation. Researchers have discovered other anomalies as well, such as curious embedded magnetic particles and charred tissue. Some of the plant stalks within the circles show evidence of being exposed to rapid microwave heating.
Scientists have attempted to explain crop circles as a result of natural processes. One popular- theory’. Accepted by many mainstream scientists and academics, is known as ‘Plasma vortex Theory’. Developed by Dr. Terence Mearden, it theorizes that electrified air(plasma), on the side of hills, become mini-tornadoes and screws down onto the ground, creating the circles. The theory also holds that the electrified air would cause a light to appear above the cicle and therefore account for UFO sightings. Although this theory still has considerable support it has come under fire because of the highly intricate and complex crop circle patterns that have appeared since 1991. Another theory is that the circles are all hoaxes or practical jokes. Major support came to this theory when, on September 9, 1991, two Englishmen claimed to have created approximately 250 crop circles. However, those circles were more ragged than others, and many were already suspect. It is irrational to believe that all crop circles are faked for publicity or other reasons. Many crop circles appeared long before the phenomenon gained large recognition from the public and press. Too many circles and patterns are formed each year in too many countries for them to have been hoaxes. Many crop circles show strange mathematical traits when analyzed.
The crop circle phenomenon is an enigma. Many dollars have been spent by researchers and their associations in an attempt to fond a solution to this intriguing puzzle which will continue to haunt humanity until an explanation is found.

Passage 3




An essay by scientist, education and environmentalist, Dr. David Suzuki

A number of books, articles and television programs have disputed the reality of the claimed hazards of global warming overpopulation, deforestation and ozone depletion. Two newspaper commentaries show the profound differences of opinion on critical issues affecting the planet.
The first, by Robert Kaplan, has generated both fear and denial. Entitled The Coming Anarchy, the report paints a horrifying picture of the future for humanity. The author suggest that the terrible consequences of the conjunction between exploding human population and surrounding environmental degradation are already visible in Africa and parts of Southeast Asia. As society is destabilized by the AIDS epidemic, government control evaporates, national borders crumble beneath the pressure of environmental refugees and local populations revert to tribalism to settle old scores or defend against fleeing masses and bands of stateless nomads on the move.
Kaplan believes what he has seen in Africa and Southeast Asia is the beginning of a global pattern of disintegration of social, political and economic infrastructure under the collapse, this scenario could sweep the planet, first in Eastern Europe and then the industrialized countries. It is a frightening scenario, built on a serious attempt to project the aftermath of ecological destruction. It comes from a core recognition that the planet is finite and consumption has vast social, political and economic ramifications. It has also generated a great deal of discussion and controversy.
Marcus Gee pronounces Kaplan’s vision ‘dead wrong’ in a major article headlined Apocalypse Deferred. Attacking the ‘doomsayers’ Gee counters with the statistics favored by believers in the limitless benefits and potential of economic growth. Citing the spectacular improvements in human health, levels of education and literacy, availability of food and length of life even in the developing world. Gee pronounces the fivefold increase in the world economy since 1950 as the cause of the good news. He does concede that immense problems remain, from ethnic nationalism to tropical deforestation to malnutrition to cropland losses but concludes that Kaplan has exaggerated many of the crises and missed the broad pattern of progress. Focusing on statistic of the decline in child mortality and the rise in longevity, food production and adult literacy, Gee reaches the conclusion that things have never been show ‘remarkable sustained and dramatic progress.’ Life for the majority of the world’s citizens is getting steadily better in almost every category.’
Gee’s conclusions rest heavily on economic indicators. He points out the out the annual 3.9 percent rise in the global economy and the more than doubling of the gross output person, that has occurred for the past thirty years. World trade has done even from 40 percent of a product’s price in 1947 to 5% today.

Gee skips lightly over such facts as third world debt and the daily toll of 22,000 child deaths from easily preventable disease. He also fails to mention that during this period the gulf between rich and poor countries has increased. He does acknowledge the threats of loss of topsoil and forests, pollution of the air, and contamination of water. However, he concludes that there is little evidence they are serious enough to halt or ever reverse human progress. Gee challenges the notion of a population crisis since there have never been as many people so well off. Furthermore, he suggests there will never be a limit to population because more people means more Einstein’s to keep making life better.

Gee’s outlook rests on a tiny minority of scientists who have faith in the boundless potential of science and technology to overcome the physical constraints of air, water and soil so that a much lager population can be sustained. His final proof? The general rise in living standard along with population growth. But the relationship between changes in living standard and population is a correlation, not proof of causal connection. Gee is ignoring basic economic as well as scientific reality.
If we inherit a bank account with a thousand dollars that earns 5% interest annually, we could withdraw fifty dollars or less each year forever. However suppose we start to increase our withdrawals, say up to sixty dollars, then seventy dollars and more each year. For many years the account would yield cash. But it would be foolish to conclude that we could keep drawing more from the account indefinitely. Yet that is what Gee believes. As ocean fisheries around the would show, we are using up the ecological capital of the planet (biodiversity, air water, soil) rather than living off the interest. It is a dangerous deception to believe that the human created artifice called economics can keep the indicators rising as the life support systems of the planet continue to decline.

The value system that dominates most of the popular media promotes the delusion that resources and economy can continue to expand indefinitely. It also blinds the public to the urgency and credibility of warnings that an environmental crisis confronts us.
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