Stop! That poo can be put to good use.

In other parts of the world, biosolids (human waste) from sewage treatment plants are treated and used as sustainable agricultural fertilizer. Research the pros and cons of this method and take a stand on whether this can be a realistic alternative to our current agricultural practices. Who are the potential stakeholders in this issue? Are we influenced by the western view of human waste as an unsanitary and disgusting nuisance?

Have you given thought to where your personal waste ends up after you flush the toilet? I know I have. Sorry if that's too much information! Does our waste just end up in the middle of no where? Can you imagine a pile of real crap, collected, in the middle of flat land?How about in the oceans? That is one imagine that would be horrible to view. As citizens we need to know how waste water is treated, and how biosolids are created.

What are biosolids? That is the first question that needs to be answered before I can contribute my two cents for this bio-blog. Biosolids are nutrient-rich organic materials resulting from the treatment of domestic sewage in a treatment facility. When treated and processed, these residuals can be recycled and applied as fertilizer to improve and maintain productive soils and stimulate plant growth.

Any water that is flushed down the toilet, through the drain, or through the shower is classified as wastewater. The wastewater travels away from its original location through a series of underground pipes. These pipes have been organized and designed by the government to allow the water to go through a filtration process. Solids, chemicals, feces, and any other undesirable material is cleaned from the wastewater, before it enters Lake Ontario. These pipes stretch for about 9 000 kilometers in total. Without treating the wastewater, bodies of water, as well as drinking water will be contaminated.

Due to Ontario's vast and concentrated population four wastewater plant treatments plants are essential: Ashbridges Bay Wastewater Treatment Plant, Highland Creek Wastewater Treatment Plant, Humber Wastewater Treatment Plant, and as well as North Toronto Wastewater Treatment Plant. Through a series of physical and chemical processes water quality expectations are achieved.

Process of Water Treatment in Toronto
1) Water travels through a series of pipes with various bar screens, disabling large objects from passing through. Items such as tree branches or rocks will be stopped at this step. After water passes the bar screen, it slows down and enters a grit tank, where debris settles at the bottom of the tank. The waste that is divided through these steps is disposed of in a landfill.

2) Water is held in another tank for several hours where more waste in the water settles at the bottom.

3) Oxygen is added to a tank of water. This addition provides an environment allowing for the growth of micro-organisms. These micro organisms eat small bits of organics, resulting in a mixture of solids with micro-organisms. This mixture then travels to a clarifier, where solids settle to the bottom

4) The wastewater, which is hardly waste at this step is finally disinfected using chlorine. Chlorine is used to kill harmful pathogens before it enters Lake Ontario.

5) All the solids that have settled to the bottom of the water tanks are sent to the digester. Micro-organisms use organic material in the solids as food and convert it to methane gas which is used to produce electricity and heat at the plant. After 15 days, the biosolids (a wet soil-like material), high in organic content and nutrients, such as nitrogen, and phosphorous can be beneficially reused as fertilizer, incinerated or sent to landfill.

In learning about the water treatment in Toronto, I observed how biosolids (human waste) from sewage treatment plants are indeed treated and used as sustainable agricultural fertilizer. In conducting this bioblog, I had certain expectations, thinking that Toronto did NOT use biosolids. Through research it is clear that this is not that case.

195 000 tones of biosolids is generated from the users of the Toronto wastewater system. Seventy seven percent of Toronto biosolids are treated at the Ashbridges Bay Treatment Plant and the other twenty three at the Highland Creek Treatment Plant. Biosolids can be reused and disposed of in a variety of methods including at landfills, used for incernations, for land applications, pelletization, alkaline stabalization, as well as site remediation.

THE PROS
It is obvious that the use of biosolids is very useful in terms of effective fertilizers. Instead of storing the biosolids in a landfill site, the biosolids can instead benefit the environment and the soil especially. Biosolids are a possible substitute for chemical fertilizers, which will be extremely beneficial in regards to the environment. It is obvious that the health of our Earth is very fragile at the moment, so every precaution will make a difference. Farmers do save money by using biosolids, due to the elimination of chemical fertilizers. Excess application of chemical fertilizers do eventually seek through the ground into the groundwater, streams, lakes and eventually oceans thanks to the rain and irrigation, creating hazards. The excess application results in pollution and damage to the natural environment. It has been questioned whether or not the growth of agriculture is equivalent in using chemical fertilizers or biosolids, and it seems as if it is. After all, biosolids are rich in organic content and nutrients, such as nitrogen, and phosphorous. They also contain elements such as magnesium, calcium, copper, iron, manganese, sulfur and zinc. Biosolids are also sometimes applied to forest land and tree nurseries. Application to strip mines can also help reclaim and vegetate the land. Numerous studies completed over the years have shown that biosolids land application is safe and has significant benefits.

THE CONS

The cons of using biosolids include the odour that it gives off due to their composition of sulphur and ammonia, important nutrients for plants. The smell of biosolids is very distinct and may aggravate individuals. The smell can be toned down by managing techniques, but this will not fully rid the smell. Another con to the use of biosolids is the presence of metals that are seen in biosolids. Excessive amounts of metals will pose a dilemma in regards to the health of animals and plants. The presence of pathogens is a concern to health officials, as they can rupture the presence of diseases in communities.

Whose choice is it?

The stakeholders in this issue include government officials, farmers, and gardeners. Neither the Minister of Health nor the Minister of Environmental Concerns view biosolids as having a significant negative impact in the well-being of the community or the environment. Farmers decide on the techniques they use for the development of their agriculture. The same goes to gardeners. The bottom line is that each and every person is a steward of the Earth, and each and every one of us are privileged with a voice, a voice that should be used and put to work to benefit society.

Works Cited:
http://en.wikipedia.org/wiki/Biosolids

http://www.toronto.ca/water/biosolids/index.htm

http://www.cwwa.ca/faqbiosolids_e.asp

Blogs Commented On:
Christina Chong

Amanda Phen

The NEED for technology

Evaluate the importance of various technologies, including Canadian contributions, to our understanding of internal body systems (digestive, circulatory or respiratory)

It quite simple, without certain technologies that are present today the health care system would be nonexistent. Many discoveries and knowledgeable information would not be known. How would the image of a cell be known without technology? The structure of the cell is one the fundamental concepts in human biology.

Health technologies form an indispensable component of the services heath systems can offer in the prevention, diagnosis and treatment of disease. Health technologies also alleviate disability and functional deficiency.

The greatest invention of the 1600s, the microscope, changed the way people understood and explained the universe. No one scientist was responsible for the development of the microscope. Instead, the development of the microscope was an ongoing process that involved technological advances in glass making and lens polishing, along with refinements to existing models. The invention of the light microscope allowed for scientists to view the contents of cells, and led to the realization that plants and animals share many common cellular features. Without the light microscope, scientists would not have known the existence of Escherichia coli, which is a colony of small rod-shaped bacteria, that lives in the human intestines. These microbes continuously supplies the human body with important vitamins, and helps break down and food we consume.
The light microscope has further developed into the electron microscope, due to James Hillier and Albert Prebus, graduate students at the University of Toronto. Since then, further developments in the field of microscopy have led to:

The Transmission Electron Microscope (TEM) which develops an image that is produced by a beam of electrons passing through a very thin slice of specimen. The image appears on a screen and is a flat, two-dimensional image.

The Scanning Electron Microscope (SEM) produces an image by a beam of electrons which scans across the surface of the sample. As secondary electrons are released by the sample, they form an image which is somewhat three dimensional.

The Scanning Tunnelling Microscope (STM) produces an image of a sample by placing a minuscule electrical probe near the surface of the sample. The images produced are used for atomic-level imaging and for manipulating molecules and atoms.

The use of the microscope has led to an understanding the structure of the cell and its functions. It provided the basis for determining how tissues and organs work. It has identified bacteria, viruses, and process that allows for a positive impact on the health care system.

A Canadian researcher, Dr. Gurmit Singh, who works at the Hamilton Regional Cancer Centre (and McMaster University) is studying the way the mitochondria of a tumour's cells differs from those of a normal cell. In healthy cells, any distribution of the mitochondria causes cellular respiration to stop, which leads to the death of the cell. In tumour cells, the abnormal mitochondria allows the cell to continue to live, increasing the size of the tumour. In Dr. Gurmit Singh's studies, he hopes to find a way to activate the normal death signals in tumour cells, allowing the destruction of the tumour.

A microscope is limited to viewing a small sample of any matter. In contrast, a computerized axial tomography (CAT) scan is defined as a procedure in which an X-ray machine takes many pictures of an object from different angles; a computer then reassembles the image to allow viewing of the object in cross section and in 3-D. The CAT scan is so accurate that it can detect abrasions as small as one millimetre. The scanner also distinguishes between gases, liquids, and solid tissues, and is able to identify tumours embedded in the bran or liver. CAT scans are particularly useful as a diagnostic tool for assessing head injuries involving blood clots.


An endoscope is a medical instrument to view the interior of the body. It can be fitted with a light-emitting glass fibre and then positioned inside a patient's body. This medical device is inserted directly into the organ and can consist of the following: a rigid or flexible tube, a light source connected to the tip of the tube, and a lens system, transmitting the image to the viewer. An endoscope was first introduces into a human in 1822, but Willian Beaumort. This device can be used to view: the esophagus, the stomach, stomach ulcers, small intestine, or large intestine (digestive system), the nasal passage or nose (respiratory system).


It quite oblivious to everyone, that the heart is one of the most important components in the human body. But does anyone wonder, is it possible to MAKE a heart? Dr. Michael Sefton, director of the Institute of Biomaterials and Biomedical Engineering at the University of Toronto, has been studying and experimenting on how it would be possible to create components of the the heart. This breakthrough in medicine would provide an unlimited number of hearts for transplant that would be grown in the laboratory.
PROCESS IN MAKING A HEART:
1) Cells are placed along plastic scaffolding. Typically, biodegradable plastics are used.
2) The scaffolding, seeding with cells, is placed in a bioreactor that provides nutrients and oxygen needed to support cell division. The bioreactor acts as an incubator maintaining constant body temperature.
3) The cells secrete proteins and growth factors that bind them together to form a living tissue on the scaffolding.

The sphygmomanometer is defined as a device used to measure blood pressure (the force of blood on the walls of the arteries). Blood pressure is traditionally measured in millimetres of mercury ( mm Hg ). A sphygmomanometer consists of a cuff with an air bladder that wraps around a human's arm, a small pump is used to inflate the air bladder, thereby closing off blood flow through the brachial artery, one of the major arteries in the arm, and a measuring unit. This device had been invented by Samuel Siegfried Karl Ritter von Basch, in 1881. High blood pressure can be a serious health problem, as it can weaken an artery and eventually result in its rupture. Equally, low blood pressure reduces the capacity to transport blood in the human body. A sphysmomanometer is important in monitoring the circulatory system and can reflect the health of the respiratory system.

In conclusion, health technologies are a major component of the health care system. Without certain technologies, many diseases would not be known, many people would die of unknown causes, and the existence of the universe and human body would still be unknown. Basically, everything would be unknown.

Blogs Commented On:
Amanda Phen

Jarvis Noronha

WORKS CITED LIST:
http://health.howstuffworks.com/question146.htm
http://www.yesmag.ca/how_work/microscope.html
http://www.radiologyinfo.org/en/info.cfm?pg=bodyct
http://www.medicalnewstoday.com/articles/153737.php
http://digestive.niddk.nih.gov/ddiseases/pubs/upperendoscopy/

THAT DOG LOOKS LIKE A WOLF!

Question: Artificial selection has resulted in plants that are more disease-resistant, cows that produce more milk, and racehorses that run faster. One must wonder what will come next. In the blog entry answer the following question - under what circumstances should humans be artificially selecting plants or animals, if any?


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We live in a very materialistic world, would you agree? Personally, I cannot shake my head at this statement, verifying that this statement is not at all, in any way true - I'd simply be lying. The other day I was conversing with my parents (such a miracle that was) brainstorming about what type of family dog we'd get. As the conversation grew, we found ourselves settling on a mix breed of a Shih Tzu and Pomeranian. It is a pure coincidence now that I find myself discussing a topic based on humans artificially selecting plants or animals for desired results.

Artificial selection can be defined as intentional breeding in hopes for certain traits/genes. Artificial selection can be achieved by purposefully altering the gene pool of a species. This is the opposite of natural breeding. In relation, we could say that artificial breeding is natural breeding with human interference. In reality, although humans may have the best interests at hand, things such as the life span and organ systems of the organisms are directly effected.

To start off, I must comment on how this topic and the previous topic are very similar with a slight variation in their contexts. In the previous bio blog we observed and discussed how it was morally wrong to "design" unborn babies to our (human) liking. With this topic, I will be observing and discussing how "scientifically" or "experimentally" or "morally" wrong it is to artificially select plants and animals to our (human) likings. See the similarities? See the differences?

The origins of artificial selection began with Charles Darwin (12 February 1809 – 19 April 1882). Charles Darwin proposed the scientific theory that the branching pattern of evolution resulted from a process called natural selection. From his research, scientists were able to elaborate on his results and manipulate the genes in an organism. As technology continued to grow (as if it ever stops), we now find ourselves being able to personally pick and choose exactly which gene we would like to have in an organism. Who was I to think that shopping online was such a milestone?

Accomplishing artificial selection can only occur with exact precision and ensured totality of achieving a goal. Scientists observe a plant or animal, distinguishing a gene that would like to be desired. Subsequently, the plant or animal is then bred with another of its kind with the same exact gene. In doing this, the ratio of the F1 phenotype will be more probable of being what is aspired for. The cycle can be repeated multiple times until the possibility of the possible offspring phenotypes is 100% exactly what is desired.


Most livestock, including dogs, cats, goats, pigs, cattle, sheep, guinea pigs, horses, and geese were domesticated more than 5 000 years ago. Domestication can be defined as an act upon humans reflecting a change in the system, more specifically plants and animals. Experts have agreed that one of the first mammalian species to become domesticated are dogs, which can been seen accurate through comparing the organism to its gray wolf (Canis lupus) ancestors. One major reason in which dogs are artificially selected when bred is to eliminate aggressive looking traits. Dairy cattle are another example of artificial selective organisms. Dairy cattle are bred in hopes of producing more milk, unfortunately some cattle suffer from problematic infections and fertility complications, due to the altering of their gene pool. Persian cats are bred in hopes of a more 'flat-faced' feature, this change has led to respiratory and digestion complications. All of these prime examples of organisms have gone through artificial selection solely for cosmetically reasons and not at all because of health related impediments.

It is clear that artificial selection has many negative side effects, through examination of specific organisms. This type of selection removes variation in a population, leading to selectively bred organisms susceptible to diseases or changes in the environment that would not cause such a complication for a natural bred population. Inbreeding can be defined as a genetic term that refers to reproduction as a result of the mating of two animals which are genetically related to each other. Inbreeding can cause a definite predicament, more specifically if both organisms contain recessive alleles, leading to deformities or even death. In dogs, inbreeding has resulted in breeds that have health issues ranging from decreased life span to hip dysplasia.

Artificial selection not only occurs in animals, but in plants as well. Corn is a well-known example of selective breeding, whom without would be more commonly known as a teosinte. In the picture, the works of artificial selection can receive its 'acknowledgments'. The image on the left is a teosinte, and on the right is its modern descendant, corn. I know I wouldn't want to be the one eating that teosinte! Cabbage, broccoli, cauliflower, brussels sprouts, collards, and kale are all members of the same species, Brassica oleracea. All of these well-known vegetables would not be known today without selective breeding.

In researching and learning about this topic, which of what I was stranger to preceding this biology blog, I was able to gather many new insights. In knowing that selective breeding has had SUCH an impact on the world, and even so my life, I cannot 'condemn' this idea to death. Would the world not be very different without selective breeding. I learned through my research that selective bred offspring do have several harmful side effects, effecting not only that organism, but can end up hurting the whole ecosystem in the end. In my opinion, everything can have a possible 'pros and cons' list, the question that still stands is whether or not it is worth the chance. Personally, I find myself optimistic about this topic. I DO believe that organisms can continue to evolve with the help of human interferences to invent new hybrids and who knows what else! With this said, I do believe that there must a 'drawing line' between what is acceptable and what should be looked down upon. Selective breeding for pure cosmetic use, for example, should not be permitted. Why risk the health of an organism just so that they will be more attractive. (Guess I should be saying the same thing to all those getting plastic surgery *cough .. Heidi Montag ) With all this said, I'll end this in commenting that 'it's not the outside that matter's, it's all that is inside'

Works Cited List

http://www.learner.org/courses/essential/life/session5/closer1.html
http://www.learner.org/courses/essential/life/session5/closer1.html
http://en.wikipedia.org/wiki/Artificial_selection
http://www.biology-online.org/2/12_selective_breeding.htm

BLOGS COMMENTED ON;

Christina Chong

Tammy Nguyen

My baby MUST have a mole right there!

Can I have my laptop customized?
Can I have my cell phone customized?
Can I have my car customized?
Can I have my BABY customized?





















What is a designer baby?
A designer baby refers to a baby whose genetic makeup has been artificially selected by genetic engineering combined with in vitro fertilization to ensure the presence or absence of particular genes or characteristics. The change in genetic information can be for either medical or cosmetic reasons, depending on the parents of the child.

Have you ever considered what a great opportunity it would be to customize your own child? Would they have green eyes? Brown silky hair? High cheek bones? If only there were gene alternating practices that aloud for this to occur. As surprising as it is, scientists are currently experimenting with genes and the capability of purposely altering a babies genetic information. For the past decade, technology has rapidly evolved. Ten years ago several people were not familiar with iPods, wi-fi, touch screen cellulars, wii, and other gaming devices. Technology in the entertainment district has sky rocketed. Can you imagine the increase in scientific technologies in the medical world? The fact that scientists are now experimenting a method to alter genes in unborn babies is astonishing.

It's true that every human being was created in the image or God. Correct? In changing the physical characteristics of unborn children, are we not turning our back on our beliefs? Some may agree, others will disagree. In my personal opinion, I believe that altering a babies physical characteristics is completely vile and insulting. When was the last time you observed a baby and commented saying, "ew"! I would hope that this had never occurred or even observed. No matter what, babies are always THE cutest things. Their small fingers and tiny toes are seen to be simply irresistible to anyone who is comprised of a heart. Those willing to change the characteristics of their child are simply hardheaded, materialistic and simply 'plastic'. All girls out there will know exactly what I'm talking about (sorry to the boys!) Not many people can resist the desire for wanted materials such as shoes, or clothes, or electronics. Developed countries such as Canada and the United States can be described as being very materialistic. Our keen eyes set out looking for those expensive brand name heels, or that new updated cell phone, or new gaming system. The desire for these materials can be seen to be understandable, yet the desire for changing a babies looks is on an entire different level! In my opinion, we should all live as great leaders such as Ghandi and Buddha once lived, ascetics.

The ability to change an offspring's genes can be seen in having a positive side. The process can be beneficial in terms of investigating illness or diseases that originate in birth. The use of pre-implantation of genetic diagnosis can avoid the possibility of the child having medical disorders such as an attention-deficit disorder or down's syndrome. This will greatly change the learning habits of children and be a positive attribute in society.


"This is cosmetic medicine. Others are frightened by the criticism but we have no problem with it." - Jeff Steinberg ( Fertility Institutes Medical Doctor )

Assisted reproductive technology (ART) is a group of fertility treatments that undergo screening of both the sperm and the egg. In vitro fertilization (IVF) is the most common type of assisted reproductive technology. In IVF, the sperm fertilizes the egg outside the body, and doctors implant it into the woman's uterus. This process is used when a couple is infertile and are seeking help to have a baby. Other forms of ART include intracytoplasmic sperm injection (ICSI), gamete intrafallopian transfer (GIFT) and zygote intrafallopian transfer (ZIFT). In testing the traits that are present in an embryo a pre-implantation genetic screening is used. P.G.S is mainly used to observe whether or not an abnormality in the embryo will be produced due to malfunctions in the genetic information. The possibility of using P.G.S's in the future for cosmetic use is very probable.

















Is true beauty not already corrupt as it is? With all the advertisements, degrading videos/pictures of women, plastic surgery, and the list continues. Female teenagers are especially found to be very vulnerable. There are many people are there that would agree that having a child is a miracle. Yet, I have to consider the fact that parents are only wanting the best for their child. Parents want that certain head start for their child in life. So the question is, at what extent are parents willing to consider to achieve this head start. Parents of a child may consider the fact that a cleft iris and large earlobes may be a heretic gene that their offspring will have, and may not want this for their child. Is this an understandable circumstance to undergo medical attention?

With all this said, I must say that the certain technology were are observing is fascinating and intriguing. I do not believe that this technology should be used for cosmetic use. A simple change such as the fact of whether a child is male or female can create a huge change in the world. Some countries such as those in Asia already prefer males instead of females, since males are still seen as being more dominant. Designer babies should only be used in term of medical reasons, which is would clearly benefit society.


http://www.bionetonline.org/English/content/db_cont1.htm

http://online.wsj.com/article/SB123439771603075099.html

http://www.actionbioscience.org/biotech/agar.html

http://singularityhub.com/2009/02/25/designer-babies-like-it-or-not-here-they-come/

BLOGS COMMENTED ON

-Angela Nisce

-Belinda Papa

IS THIS EVEN A QUESTION?

Question: Many scientists consider humans as the most invasive species, as humans can greatly change an environment and impact living things that reside there. Are we being stewards of the world? Take a look at an issues in which human intervention has positively or negatively affected the biodiversity of our ecosystems.

















Our world is evolving... No doubt about that. But, can we really, truthfully, sincerely tell someone that being a steward of the world is one of our main priorities in life. These days, many people are so caught up with their dilemmas and duties, that they are not attentive to how they are treating their home. That's our problem right there. Many people would ONLY describe their home as being the place in which their family resides at, when really, the whole world is our home (yeah, a tad corny, but nonetheless very accurate). It's obvious that many of us would not litter inside our house, who would? Maybe only those who aren't scared of a raging mother lecturing us on how different her life was as a child, and how hard her duties and consequences were. So, for all those good kids who do listen to their mothers (hats off to you!) we instead take the time to get up off our butts (very rare occasion, indeed) and actually throw our garbage into the trash can.

Humans are the smartest mammal on the Earth. Correct? So, should we not realize that the car that we choose to go into, for that ten minute ride to school, is polluting our atmosphere? Or that the litter that we carelessly throw onto the road, is dirtying our Earth? Or that the computer that we leave on, all day is causing the burning of fossil fuels? It seems that everything that we do in our daily routine, somehow always has a negative effect on the world.

One of the most major environmental problems is global warming. Our Earth was once protected by a once secure and strong ozone layer. The ozone layer protects humans from the sun's harmful rays, such as the ultraviolet rays (UV-B). Through the years, scientists found that certain man-made products damaged the ozone layers, making us more vulnerable to the sun's rays. Scientists have found that the production and use of chemicals like chlorofluorocarbons (CFCs) in aerosol sprays, refrigeration, insulation and air conditioning was contributing to the accumulation of ozone-depleting substances (ODS) in the atmosphere.

The damage to the ozone layer does have a impact on the human population. The thinning of the atmosphere increases the chances of skin cancer and also cataract in the eye, children being especially vulnerable. Personally, I love being outside in the sun. I could spend countless hours with the sun's rays beaming down on my face. The fact that harmful ultraviolet rays are becoming more and more of a hazard, concerns me. I would never wish upon skin cancer, or any other sickness, due to the amount of time I spend outside under the sun.

Increased UV-B rays impacts biodiversity since it reduces levels of plankton in the oceans and subsequently diminishes fish stocks. It also impacts plant growth, resulting in decreased agricultural productivity, effecting herbivores, which will affect omnivores and the chain continues.

We can see how global warming has had an effect on our world, by looking at the polar bear population. The polar bear, or also known as the Ursus Maritimus, is native to the Artic Circle. Polar bears can also be found residing in Alaska, Russia, Norway and Greenland. Approximately sixty percent of the species population can be found in Canada. Polar bears have a life span of around twenty to twenty-five years. The species spend their time in ice cold water, or on sea ice. The sea ice is used by the polar bears as a hunting platform to catch marine mammal prey. Without the presense of sea ice, they have difficulty meeting their dietary needs.

Due to global warming, temperatures in the atmosphere are continuously increasing. The temperature in the Artic Circle is rising twice as fast than the rest of the world. Since 1978, sea ice cover has declined by approximately nine per cent per decade, and the rate of melting appears seems to be on the rise, as years go by. Studies have been shown that with the ice melting quickly in the Artic Circle, the polar bears are being robbed of the ices floes. This resusts in the polar bears being forced ashore. This increased amount of time on land leads to weight loss, physical deterioration and decreased rates of reproduction. It is predicted that by 2012, the polar bear population in the Western Hudson Bay, will by unable to reproduce.

Can you imagine this? The whole polar bear population being wiped from the face of the Earth? Does that not strike a signal in your mind that the human poulation have done much damage? IF things do not start chnaging, it won't be soon until many other animal populations become endangered. Change needs to happen, and it needs to happen quickly.

WORKS CITED
http://www.davidsuzuki.org/Conservation/Endangered_Species/Canada/polar_bear_facts.asp?gclid=CPvhjL6gzp0CFZho5QodVB24yg#

http://www.worldviewofglobalwarming.org/

http://globalwarming.com/

http://www.naturecanada.ca/advocate/polar_bears.html?gclid=CMz1gdanzp0CFcZM5QodL01HsQ