Around the world economic development is at odds with the preservation of our environment. Capitalism is quickly eroding away at that which we need for our survival. If there is a global free market economy the complete destruction of our environment is inevitable. As a result of this human extinction is in the very near future. The survival of humanity depends on us acting now to stop this assault of capitalism on the planet. These are bold statements so I will now show you my proof.
Constanza et al published a report in 1997 that tried to put a price tag on the value of basic ecosystem services. See Table 1. This report synthesized results from more than 100 published studies and used a variety of evaluation methods to look at the value of 17 basic ecosystem services across the planet. The report came up with an estimate for the value of earthís ecosystem services of $33 trillion US. This $33 trillion dollars is a very conservative estimate as it omits all of the processes that we have yet to understand (Pimm, 1997). For comparison the global GNP is about $18 trillion dollars. This shows us that the environment is more important to us than our economy.
We take these ecological services for granted because they are free. But when we have to replace them after we have destroyed the ecosystem it costs much more. Recently, New York City projected that to build the new water treatment plant that the city needed would cost $6 billion to $8 billion (Stapleton, 1997). So instead they protected the watershed that had traditionally purified their water for free. Buying land around its reservoirs and instituting other protective measures cost only $1.5 billion. Saving the watershed benefited the people as well as the wildlife.
Biodiversity is an important part of our environment. We use a wide range of organisms for many essential functions. Over 3,000 antibiotics have been developed from microorganisms (World Wildlife Fund, 1993) and up to 70,000 species of plants are used in traditional medicine (World Wildlife Fund, 2000a). The more species that there is the more that is available to us. This leads us to the Precautionary Principle, which tells us that we should keep as many species as we can to ensure that we will have what we need when we need it.
Biodiversity helps our ecosystems provide us with essential services. ìBiological diversity is the key to the maintenance of the world as we know itî (Edward O. Wilson, 1992). Elton first proposed the role of biodiversity in ecosystem function in 1958. He proposed that increasing biodiversity in an ecosystem increased the stability of that ecosystem and made it more resistant to change. This happens because as species richness increases productivity of that ecosystem increases as well, and the variability of that ecosystem decreases. See Figure 1.
This has since been substantiated in several empirical studies. McGrady-Steed et al have shown that increased species richness increases productivity and decreases variability in aquatic communities. Using microcosms Naeem and Li (1997) have shown that increasing biodiversity increases the reliability of an ecosystem. And Tilman et al (1996, 1997), have shown increased productivity and sustainability with increased biodiversity in grassland plots. Tilman et al (1996, 1997) also showed that diverse ecosystems could recover faster from catastrophic events.
This increased productivity and decreased variability means that biodiverse ecosystems are much more reliable and more likely to persist. Biodiverse ecosystems can better deal with change. A quote from Naeem and Li (1997): ìBiodiversity represents a form of biological insuranceî. We need this biological insurance for when disaster strikes. Things happen in natural systems and they fluctuate. There are fluctuations that are very frequent and have little effect on ecosystems, such as daily weather patterns. Fluctuations that are less frequent have a greater effect (Lawton, 1997). The drought of the 1980ís is an example of this. Ecosystems can survive these fluctuations because of the adaptability that results from their biodiversity.
Occasionally there are huge catastrophic events that have enormous consequences on the ecosystem (Lawton, 1997). The stability in an ecosystem that results from its great biodiversity enables the ecosystem to survive these catastrophic events. If we reduce biodiversity and degrade our ecosystems, they may still appear to be functioning but they do not have the stability to cope with these infrequent catastrophic events. And these huge catastrophies may be very infrequent, but they are inevitable. The 100-year flood doesnít happen very often, but it will happen. Biodiversity is our insurance against the 50 thousand year flood.
What are humans doing to biodiversity? There have been five major extinctions since the origin of life some 3.7 billion years ago, one each in the Ordivician, Devonian, Permian, Triassic, and Cretaceous (Wilson, 1992). See Figure 2. In each of these extinctions from 12% to 54 % of the planets biodiversity was lost. Recovery from these extinctions took from 20 to 100 million years (Wilson, 1992). Humans have increased extinction rates so that they are 100 to 1000 times greater than background extinction rates (Lawton, 1997). Projections into future indicate that extinction rates will increase to 10,000 times the background rate (Lawton, 1997).
We are in the middle of the sixth mass extinction. The drop biodiversity today is approaching if not already exceeding that of the Cretaceous extinction when the dinosaurs died out. It is hard to measure extinction rates, but the best estimates indicate that today there are four species go extinct every hour (World Wildlife Fund, 2000). What has already gone extinct? 25% of the bird species have went extinct in the last 200 years (Vitousek et al., 1997) and 11% of the surviving species are endangered (Wilson, 1992). 18% of mammals in the world are endangered (Vitousek et al., 1997). 20% of worlds freshwater fish are extinct or in state of dangerous decline (Wilson, 1992). In United States 230 species of plants have went extinct, and 680 are in danger of extinction (Wilson, 1992). In western Europe half of the fungi species have went extinct in the last 60 years (Wilson, 1992). In western Germany 34% of insect and other invertebrate species endangered (Wilson, 1992). COSEWIC (1999) determined that there are currently 340 species and populations at risk of extinction in Canada.
It took the planet 100 million years to recover from the Permian-Triassic extinctions. And human degradation of the environment is reducing the planetís ability to recover what it has lost. And to recover from this mass extinction, the mass extinction first has to end. This current mass extinction event shows no signs of slowing; in fact it shows every indication of accelerating.
Why are we having such an effect on the other organisms that we share this planet with? We are having this effect because we are changing the face of the planet. See Figure 3. About half of earthís land surface has been transformed by human activity, over half of assessable freshwater is used by humans, humans fix more nitrogen than all natural sources do, and there has been a 30% increase in atmospheric CO2 since Industrial Revolution (Vitousek et al, 1997).
In 1986 Vitousek et al determined that 40% of the planets net primary activity was used or destroyed by humans. Since the human population has increased 26% since they did their study, I would extrapolate that now humans probably use or destroy over 50% of the net primary productivity of the planet. It is interesting that of all of this net primary productivity that we steal from the planet, we only actually use 8% of it for food, fuel, or construction.
The Living Planet Index is a calculation of the change in the health of the earthís ecosystems (World Wildlife Fund, 1999). To measure the health of the earthís ecosystems the index looks only at the amount deforestation and the decrease in populations of cataloged freshwater and marine fish species. This is a very conservative estimate as it does not include many of the earthís major biomes such as grasslands, and it only accounts for environmental degradation by logging. Using this index the health of the earth has declined 30% since 1970. See Figure 4. Using Costanzaís data for the value of ecological systems, this means that we are losing $1 trillion a year as a result of environmental destruction.
All of the biomes on the planet are being destroyed. In North America over 90% of the native prairie has been destroyed since European settlement while fragmentation, recreation, invasion of foreign species, and overgrazing threatens the remainder (Samson and Knopf, 1994). In North America our grassland species are more threatened than any other group of species in North America (Samson and Knopf, 1994). Agricultural erosion in North America exceeds the prairies ability to tolerate loss, and this threatens the resource that provides us with almost all of our food (Samson and Knopf, 1994). Also, the destruction of our grasslands is adding CO2 to our atmosphere. Grasslands provide an excellent carbon sink to remove CO2 from our atmosphere and lose 30% of there carbon storage ability when they are tilled (Samson and Knopf, 1994).
Human introduced species are also wreaking havoc on our grasslands. There are currently 26 million acres and climbing of crested wheat grass in North America (Lesica and DeLuca, 1996). It forms monotypic stands and causes increased soil erosion, increased pest outbreaks and reduced soil quality (Lesica and DeLuca, 1996). And yet we continue to plant it. In fact, the U of L has planted crested wheat grass over the entire campus (Crawford, personal observation).
But most people donít care about grass. So I will focus on trees. Forests are also very important to preserve. 90% of terrestrial biodiversity is in forests so to conserve biodiversity we must conserve the forests (World Wildlife Fund, 2000). Our forests provide us with air and water. They sequester about one billion tonnes of carbon. Deforestation puts about one million tonnes of that back into the atmosphere each year (Dixon et al, 1994). They regulate hydrological cycles, effect precipitation, weather patterns, and capture fresh water for us (World Wildlife Fund, 2000). They prevent erosion, silting of waterways, and desertification (World Wildlife Fund, 2000). They provide habitat for 90% of the terrestrial organisms on the planet. Unfortunately they also give us wood and paper.
Humans consume on average 0.578 cubic meters of wood per person annually (WRI, 1997) and wood consumption is projected to increase 25% in the next 10 years (FAO, 1999). That is a lot of wood when you consider that there are 6 billion people. Canada is the 9th worst nation for wood consumption (WRI, 1997). The average person in the US consumes 333 kg of paper a year (WRI, 1997), and Canada is probably about the same. Paper consumption will increase 50% in the next 10 years (WRI, 1997).
What is the result of this demand for dead trees? Throughout the temperate zone, large transnational timber companies move into the forests with massive machines which indiscriminately hack down trees, bulldoze plants, and leave nothing but bare earth behind. The worldís forest decreased 13% from 1960 to 1990, a change of about 5 million km2 (WWF, 1999). See Figure 5. Because of human activity only one half of the worldís original forests remain (WRI, 1997).
Currently, 12 million hectares of forests are cleared annually worldwide (about 20 rugby fields a minute), seven square miles of tropical forest cleared each hour, and an acre of Canadian wilderness is logged every 13 seconds (WWF, 2000). And our forests have more to worry about than just being cut down. Fragmentation and introduced species threaten the remaining forests. Only 20% of forests remain in large, relatively natural ecosystems -- what are known as frontier forests (WRI, 1997). And 39% of Earth's remaining frontier forests are endangered (WRI, 1997).
What solutions are there? Timber corporations are trying out tree plantations. This is where they move in and clear cut a forest leaving nothing but barren ground, and then plant an unnatural monotypic forest in its place. When these trees are big enough they cut them down again, in a supposedly sustainable manner. However, only 25% of the worldís lumber comes from such plantations (WWF, 1999). And these monoculture tree stands of same age trees are not natural. Even after fifty years of growth it was found that plantations only had 15% of the myccorhizal fungi and 40% of the liginous fungi that old growth forests had (Sippola et al, 1999). These fungi are important parts of a functioning forest ecosystem. Many native organisms simply cannot survive in a monotypic tree plantation.
Less destructive methods of logging, such as selective felling, can be employed. But transnational timber companies only clearcut. Over half of the timber harvested in Alberta, and in Europe is used for paper production. Because much of the timber harvested is used for paper production it is important that there are alternatives for paper. Hemp can produce paper of equal or higher quality as wood pulp, and it is much more efficient (RAN, 2000). Hemp plantations totaling about 4 million ha, about one sixth of what is annually logged just in Canada, could satisfy the entire planetís paper demand (WRI, 1997). But this is not happening. And of course the most important solution to deforestation is to reduce wood consumption, but wood consumption is rising rapidly.
Humans are not curbing the destruction of their environment. Humans are driving species to extinction at a rate of four each minute, destroying habitats faster than we can understand and making ecosystems around the world dangerously unstable. We are eroding away at the very foundation that supports us.
See Figure 6. It is a picture of London growing over time, and a picture of brain melanoma. Why compare humans to cancer? Gregg was the first to propose this in 1955 when he wrote about humans as a medical problem of the planet. Hern has recently added support to this idea of humans as a carcinogen in his publication in the journal BioScience in 1993. Humans are like a cancer of the planet in several key aspects. Humans are no longer bound to the specific ecosystem in which we evolved, and they are experiencing uncontrolled population growth which is destroying their surroundings. If humans are a cancer of the planet what will happen? Cancer grows and takes nutrients from its host until the host organism can no longer survive and dies. Then the cancer also dies.
What really is going to be the effect of humanityís attack on its environment? Maybe we already have an example of what will happen (Wilson, 1992). People settled in most of the islands in the Pacific thousands of years ago. When they first came to the islands they had quite an adverse effect on the native flora and fauna. In some of the islands, such as Easter Island and Henderson Island, people settled destroyed 50% of the biodiversity on the island. Then they starved to death and the islands have remained empty of humans since.
Will this happen on earth? A study by Crosson in 1994 showed that since 1945 there has been on average a 17% decrease in food production across the planet. We appear to be getting more food because we are changing agricultural practices, but in reality our relative food yield from the planet is decreasing. And recovery from this could take 100 million years if previous trends after mass extinctions are an indication (Wilson, 1992). The earth is simply big enough that we havenít starved to death yet.
Recovery of our ecosystems seems a long way off, and it is not possible as long as things are getting worse. The International Energy Agency (1997) has reported that global energy use has increased 70% since 1971 and is projected to continue this steady increase. By 2010 global energy consumption is to rise another 50%. We are not using our planet sustainably. In its 1998-99 report the World Resources Institute determined that the amount of energy that the world economy burns every day required the planet 10,000 days to produce. And the only reason that we are only using that much is that most of the world does not have the opportunity to be as destructive as the western world. The developed 25% of the human population uses 70% of the resources (Goldemberg, 1995).
By the age of eight, the average Canadian child consumes sixteen times more resources than the average person in a developing country will consume in a lifetime (WRI, 1999). This shows great social inequality. But equality is not possible. Even in the short term, it would require four planets to support all humans to western standards (WRI, 1999).
There is not much evidence that human population growth will stop or that our trends of resource use will drastically change. The planet is experiencing massive declines global biodiversity, reductions in ecosystem complexity, and serious if not irreversible instability in all ecosystems. Current trends indicate a high likelihood of human population overshoot, collapse, and extinction within 400 years (Hern, 1993).
Why is this happening? We know that we are not sustainable. We know that our environmental destruction will end up costing us money. We know that we are driving ourselves to extinction. And yet we are not changing. This is happening because sustainability is not economical.
A simple model can show the economics of sustainability. In Figure 7 growth of the population being harvested is compared to the growth of money. The growth of a population is dependant on how large that population is, with zero growth at zero population size and at the carrying capacity size for that population, and some positive growth for population sizes between these two sizes. Money grows at the constant rate of the interest rate. The most economical strategy for using a resource is to maintain the population at the point were the growth of the money equals the growth of the population.
In a situation of a slow growing resource or high interest rates, the money will always grow faster than the population (see Figure 8). In this case it is most economical to completely destroy the resource as fast as possible and then bank all of the money and live off the interest. This economic model was used by Clark (1973) to show why extinction of whales was inevitable. Money grows faster than whales. Unfortunately money can grow faster than a lot of things. The average age of a tree in BC and Alberta is 100 years. A hundred year old tree takes a long time to grow. This is a slow growing resource, just like the whales. Really, what the transnational timber corporations are doing makes a lot of sense. It is not economical to sustainable harvest our trees.
Unfortunately, even if the resource can grow faster than the interest rate, complete destruction may still be the most economical choice. The problem is that the money that the entire resource is worth is often worth more than the value of the amount of the resource that can be sustainably harvested over time. Money now is worth more than money later by more than just the interest rate. Inflation must be included, and the uncertainty of the future. There is a chance that you might not always be able to harvest a resource: the population may go extinct in the future, or environmentalists might get it protected. If the resource isnít always going to be there you cannot harvest it indefinitely and the best option is to destroy that resource and bank the money.
Gordonís (1954) fishing model shows a further problem in the economics of sustainable harvesting (Figure 9). The level of fishing that is most economical may indeed be ecologically sustainable, but this still will not save the resource. There is more than one person, and in a capitalist system people will try to do something as long as there is a profit to be made. As long as there is profit the fishing effort will increase, up until the point were fishing is no longer profitable. At this point the harvest is no longer sustainable.
There is even another problem with the economics of environmental sensibility. An individualís actions often have wide spread effects. The cost of global warming to humanity is spread out over every person. When you drive your car the cost to all of humanity of that extra CO2 in the atmosphere is probably greater than the benefit to you of getting where you were going. But that cost is divided up 6 billion ways before it gets to you. So the most economical thing is for you to drive your car. This analogy can also be applied to nations to explain why no nation is lowering its CO2 emissions. Global warming will cost any country more than it gains by burning fossil fuels, but it is still not economical for a country to stop burning fossil fuels, it is only economical for every other country to stop burning them. Unfortunately, most environmental destruction, such as deforestation, acid rain, nitrogen dumping, and ozone depletion, has widespread effects.
Because of how the economics of environmental sensibility works, economic indicators such as GNP are very flawed measures of both economic progress and sustainability. Such measures do not account for the degradation in ecological services that industry and commerce cause. And any sort of free market approach to determining strategies of resource management is fundamentally flawed. It is this sort of approach to policy making that makes human extinction inevitable in the next 400 years. Sustainability is impossible and human extinction inevitable under a free market system. Globalization under a free market economy will destroy us. Globalization is not possible until developed world develops a sustainable economy.
The global market does evaluate according to GNP and it does base its decisions on the model of a free market. The WTO is the ultimate in policy making according to the free market. And what has it done for the environment? Every time big industry has used the WTO to challenge environmental protections in the name of profit, big industry has won. The Marine Mammal Protection Act, Endangered Species Act, and Clean Air Act were all found by to reduce corporate profits, and the WTO ruled to weakened these environmental protections to increase short term corporate profit at the expense of the environment.
The Marine Mammal Protection Act banned the import of tuna to the US from countries whose fleets use fishing methods that kill dolphins. In 1992 this law was challenged under GATT (the WTO's predecessor) on the grounds that it was a barrier to trade. A dispute panel ruled against the Marine Mammal Protection Act. US supermarkets once again sell tuna that is caught using methods that kill thousands of dolphins each year.
The Endangered Species Act banned shrimp imports to the US from countries that do not use devices designed to keep endangered sea turtles out of shrimp nets. In 1995, four nations challenged this law, claiming that it violated the rules of the WTO. Last October, the WTO ruled against the US ban on unsafe shrimp imports. The US government now has to weaken its Endangered Species Act.
On behalf of its oil industry, Venezuela charged that a provision in the US Clean Air Act requiring cleaner gas was biased against foreign oil refiners and therefore created a barrier to international trade. The WTO agreed, ruling against the Clean Air Act and requiring the Environmental Protection Agency (EPA) to rewrite the clean-air rules. The US government has weakened its Clean Air Act regulations.
Because the WTO has yet to accomplish anything major, there are not yet any cases of huge environmental damages as a result of its actions. But there soon will be. The US government is pushing to try to get the Global Free Logging Agreement put in place. This agreement will rapidly eliminate tariffs on all wood products and eliminate non-tariff trade barriers. This would make timber companies in the US and Canada more competitive in the world market by increasing logging. The Finnish consulting firm Jaakko Poyry estimates a 4% increase in wood consumption and harvesting as a result of removing these tariffs. Increasing the rate of harvest of our forests does not benefit us.
And what are these non-tariff trade barriers that will be eliminated? Possibly laws to protect forests from invasive pests, recycled content requirements for office and news paper, eco-labeling and "smart wood" laws, and bans on the export of raw logs and wood chips. Other forest and species protection laws may be challenged as well. Overall the global free logging agreement would increase the rate of destruction of our forests and reduce our ability to protect them.
The US did not succeed in putting the Global Free Logging Agreement through at the WTO meeting in Seattle, at least partly because there was several thousand tree hugging hippies standing outside the conference building getting tear gassed. But the US has not given up. They will probably try to push for the Global Free Logging Agreement again when the World Bank, IMF, and WTO meets in Washington DC on April 17. We need another few thousand tree-huggers with gas masks.
Why do we have to be fighting for that which should be obvious? Why isnít the method of policy making for managing our global resources being changed to something that has a hope of producing sustainable, environmentally sound decisions that wonít drive us to extinction in the next 400 years?
It is in the best interest of big industry to maintain the status quo on environmental destruction. It is benefiting them as far into the future as they are capable of seeing. And since our government is merely an extension of big industry, our governmentís policies reflect this. Take Alberta government for an example (information from Laird, 2000). Oil and gas revenues are one third of the income of the Klien government. Oil companies are very generous donators to Tory election campaigns. Several of Klienís personal advisors are from Alberta Energy Co. Havelock (the Economic Development Minister) and six other Tory MLAs started Tory Oil in 1995, which has bought into five oil wells. Mr. Havelock has been a founding member of three other Tory MLA owned oil companies since 1995. Currently six Tory cabinet ministers have active financial declared interests in oil securities and energy companies. This includes Gary Mar, the Minister of the Environment.
It is not surprising that there is no significant action being taken against the environmental destruction of the oil companies. Instead, the Alberta government is cutting back on the enforcement of its environmental regulations. The oil companies do not need to follow even the limited regulations that Alberta has in place, as there is no regulatory body to police them.
Just how far into the mechanisms of global decision-making does the long arm of big industry money reach? I will look at two examples of global decision-making.
Hormone implanted beef contains elevated levels of both naturally occurring and synthetic compounds, some of which increase cancer risk (information taken from Buchanan-Smith and McEwen, 2000). Because of this the European Union does not want to import hormone-implanted beef from the US. Last year the FAO/WHO reviewed all of the available information on beef hormone implants to determine whether these implants were harmful to people eating meet.
The FAO/WHO found that women exposed to the levels of hormone found in implanted beef did not exhibit a normal hormone response to that hormone. They then concluded that hormone implanted beef was completely safe and that the European Union had to buy beef from the big industries of the US. Whether or not implanted beef was actually harmful to people was never even looked at. In fact, there have been tests showing that hamsters exposed to these low levels of hormones developed tumors, but these results were ignores.
Global warming also seems to be a bit of a controversy in the public eye. But the Intergovernmental Panel on Climate Change, which was established by the United Nations and the World Meteorological Organization, consists of a panel of 2,500 scientists, and has to have its reports reviewed by many other scientists and governments, concluded that global warming was a fact, it was human caused, and that it would have long reaching effects. Global warming is a controversy only because of big industry money.
The big industry financed Fraser Institute, after reviewing all available information, concluded that (direct quote, Jones, 1997): ì The balance of evidence suggests there is, at best, a very small human influence on global climate. Öhistory shows a statistically significant net coolingÖ Imposing severe 'remedies' likely will be misdirected, ineffective, unproductive and economically damagingî. When an institution as influential as the Fraser Institute makes such statements, what is the result? Canada is not decreasing its CO2 emissions to comply with the Kyoto Protocol.
If devastating environmental destruction and human extinction are inevitable in our current economic system, and if those who benefit from the status quo control our policy makers so that they wonít act in the way that benefits all of humanity, what can we do? We can act now to make something happen. Direct action can save us. The awesome power of the WTO was no match for the 10,000 protestors that appeared in Seattle to block the streets with peaceful protests, dance, music, street theater, and teach-ins. Despite massive police efforts to crush the protests, the WTO was exposed and accomplished little. See Figure 10 for scenes of the WTO. We do have the power to stop transnational corporations from wiping out humanity if we act against them!
The Rainforest Action Network has just finished a two-year international campaign of civil disobedience and hundreds of demonstrations against the Home Depot (Figure 11). The Rainforest Action Network stopped their campaign because Home Depot has announced that it will phase out its sale of old growth forest harvested lumber. Home Depot is the largest retailer of lumber in the world. After similar actions by the Rainforest Action Network, Menard's, HomeBase, and Wickes Lumber, the third, sixth and tenth largest home improvement retailers in the U.S, have also announced their intentions to stop selling wood from old growth forests.
If we take action we can effect
change. On March 11th there
is a non-violent civil disobedience workshop here at the university. The facilitator is Alan Keane, an
activist and BEAR Society director.
Alan is an inspirational and knowledgeable speaker.
Come out and learn the laws so you
understand your rights, explore perspectives on non-violence including
and media aspects, and gain knowledge of how to prepare for an action. Educate yourself to act and be empowered to
Table 1. The monetary value of some selected ecosystem services on an annual basis measured in trillions of US dollars. Adapted from Costanza et al., "The Value of the Worldís Ecosystem Services and Natural Capital," Nature, Vol. 387 (1997), 256, Table 2.
ECOSYSTEM SERVICES VALUE
Soil formation 17.1
Nutrient cycling 2.3
Water regulation and supply 2.3
Climate regulation (temperature and
Flood and storm protection 1.1
Food and raw materials production 0.8
Genetic resources 0.8
Atmospheric gas balance 0.7
All other services 1.6
Total value of ecosystem services 33.3
Figure 7. The growth of the population being harvested compared to the growth of money. K is the carrying capacity for that population. Maintaining the population at size c is the most economical strategy. Adapted from Lande et al., ìOptimal harvesting, economic discounting and extinction risk in fluctuating populationsî, Nature, Vol. 372 (1994), 88.
growth of the population being harvested compared to the growth of
conditions of a slow growing resource and high interest rates. K is the carrying capacity for that
population. Maintaining the population
at size 0 is the most economical strategy.
Adapted from Lande et al., ìOptimal harvesting, economic
extinction risk in fluctuating populationsî, Nature, Vol. 372 (1994),
Figure 9. The cost-benefit of fishing compared to the amount of effort put into fishing. As fishing effort increases the cost of this effort increases linearly but there is decreasing returns on this effort. Maximum profit is achieved at point max, but new fishermen continue to enter into the business until point c were there is no longer any profit.
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