According to Jerry Coyne, ecosystems are incredibly vulnerable. As he addresses, “island ecosystems… are fragile things, easily ravaged by foreign invaders who can destroy habitats and species,” (110). The worst, as he adds, are humans themselves. We’ve seen the destruction of the rainforests for trees and land, as well as land in our own towns destroyed to make homes and buildings. As Coyne continues, “each species represents millions of years of evolution and, once gone, can never be brought back” (110). What lengths are humans going to to protect ecosystems and preserve their habitants? Also how are we restoring habitats that might have been damaged by humans? Coyne’s also brings up the point that we bring over organisms into different habitats that the environment isn’t adapted too. Give an example of an animal that has invaded a foreign habitat and the results of its invasion. If possible, explain how humans are trying to fix the problem and restore balance to that environment.
Friday, April 9, 2010
Destroying Life's History?
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More recently, as global warming as taken a more central spot on the minds of the American people, humans are going to greater lengths in order to protect ecosystems and preserve their habitats. In 1970 the Environmental Protection Agency was founded in order “to protect human health and the environment” (http://www.epa.gov/epahome/aboutepa.htm). Although this agency focuses mostly on the American people, through globalization the world is more interconnected than ever before. In order to pursue a cleaner and healthier environment for the American people, the human species as a whole must work together to improve the world.
ReplyDeletePerhaps the most publicized way of going about saving the environment has to do with automobiles. Currently, most of the cars in the world run on gasoline which excretes toxic gases to the environment, furthering disintegrating the ozone layer which is heightening global warming and killing off several ecosystems. One way of going about saving this is the Smart Car. The Smart Car has an estimated 41 miles per gallon highway, which saves a lot of gasoline (http://www.smartusa.com/green-life.aspx). The same source talks about how if every vehicle sold in the US was a Smart Car, then 24,242 miles of roadway (which is just under the circumference of the earth). Freeing up these miles of roadway would decrease the amount of ecosystems being destroyed for the human race.
Once the ecosystems are destroyed or damaged, it is vital that we as a species do everything in our ability to restore the damaged ecosystem. Trees, Water, and People (TWP) is an organization that goes about doing this. This nonprofit organization was founded in 1998 and is responsible for the planting of over 1,000,000 trees in the US and Central America (http://www.replanttrees.org/about/about.htm). Replanting trees creates ecosystems for organisms that rely on trees to live such as woodpeckers, and also reduces the carbon dioxide in the air as trees absorb carbon dioxide in order to grow through photosynthesis. This makes the air more filled with oxygen which enables human beings to breathe, survive and reproduce.
In responding to the part of the question that talks about how organisms are brought into different habitats that the environment isn’t adapted to, I believe we have learned about this in class already and this type of phenomena is called an introduced species. The 8th Edition AP Biology by Campbell defines an introduced species as a species moved by humans, either intentionally or accidentally, from its native location to a new geographic region. The book also adds that there are over 50,000 introduced species in the United States alone, and that worldwide about 40% of all the extinctions recorded since 1750 have been caused from introduced species. The book mentions the brown tree snake as an introduced species to Guam.
Sometime after World War II and before 1952, the brown tree snake was accidentally transported from the South Pacific (its native region) to Guam, most likely as a stowaway in ship cargo (http://www.fort.usgs.gov/Resources/Education/BTS/). Since the introduction of the brown tree snake to Guam, 12 species of birds and 6 species of lizards, which the brown tree snake preyed on, have become extinct on Guam. : - )
More recently, as global warming as taken a more central spot on the minds of the American people, humans are going to greater lengths in order to protect ecosystems and preserve their habitats. In 1970 the Environmental Protection Agency was founded in order “to protect human health and the environment” (http://www.epa.gov/epahome/aboutepa.htm). Although this agency focuses mostly on the American people, through globalization the world is more interconnected than ever before. In order to pursue a cleaner and healthier environment for the American people, the human species as a whole must work together to improve the world.
ReplyDeletePerhaps the most publicized way of going about saving the environment has to do with automobiles. Currently, most of the cars in the world run on gasoline which excretes toxic gases to the environment, furthering disintegrating the ozone layer which is heightening global warming and killing off several ecosystems. One way of going about saving this is the Smart Car. The Smart Car has an estimated 41 miles per gallon highway, which saves a lot of gasoline (http://www.smartusa.com/green-life.aspx). The same source talks about how if every vehicle sold in the US was a Smart Car, then 24,242 miles of roadway (which is just under the circumference of the earth). Freeing up these miles of roadway would decrease the amount of ecosystems being destroyed for the human race.
Once the ecosystems are destroyed or damaged, it is vital that we as a species do everything in our ability to restore the damaged ecosystem. Trees, Water, and People (TWP) is an organization that goes about doing this. This nonprofit organization was founded in 1998 and is responsible for the planting of over 1,000,000 trees in the US and Central America (http://www.replanttrees.org/about/about.htm). Replanting trees creates ecosystems for organisms that rely on trees to live such as woodpeckers, and also reduces the carbon dioxide in the air as trees absorb carbon dioxide in order to grow through photosynthesis. This makes the air more filled with oxygen which enables human beings to breathe, survive and reproduce.
In responding to the part of the question that talks about how organisms are brought into different habitats that the environment isn’t adapted to, I believe we have learned about this in class already and this type of phenomena is called an introduced species. The 8th Edition AP Biology by Campbell defines an introduced species as a species moved by humans, either intentionally or accidentally, from its native location to a new geographic region. The book also adds that there are over 50,000 introduced species in the United States alone, and that worldwide about 40% of all the extinctions recorded since 1750 have been caused from introduced species. The book mentions the brown tree snake as an introduced species to Guam.
Sometime after World War II and before 1952, the brown tree snake was accidentally transported from the South Pacific (its native region) to Guam, most likely as a stowaway in ship cargo (http://www.fort.usgs.gov/Resources/Education/BTS/). Since the introduction of the brown tree snake to Guam, 12 species of birds and 6 species of lizards, which the brown tree snake preyed on, have become extinct on Guam. : - )
Sorry for posting that twice!
ReplyDeleteThe first time it didn't come up until I posted it the second time.
As Coyne states, when organisms occupy new habitats, chance and law come together to explain the evolutionary adaptations and change these organisms experience, soon giving rise to new species while filling such ecological niches. The reason species on islands are more vulnerable when they encounter parasites/predators is that they have experienced less diversity and are not skilled at coexisting with other species (Coyne 110).
ReplyDeleteIn Campbell chapter 56, Campbell states the fact that humans have altered and possibly have disrupted the energy flow and other ecosystem processes that govern the natural world. But with the use of conservation biology (integrating ecology, physiology, etc to conserve biological diversity) and restoration ecology (applying ecological principles to return ecosystems that have been disturbed by human activity to their natural state), hopefully the three levels of biodiversity (genetic, species, ecosystem) may be preserved.
Humans are trying their best to use technology and improve gene diversity. For example, scientists have succeeded in breeding the resistant-strain of Indian rice (Oryza nivara) into commercial rice varieties (Campbell 1246).
The US Endangered Species Act has also placed restrictions to hinder the hunting of threatened or endangered species. Hunters have sold bats (“flying foxes”) as luxury foods and because the extinction of flying foxes may harm the native plants of the Samoan islands, conservation biologists are seeking ways to reduce this pressure to hunt.
Wetlands in the US have been drained and converted to other ecosystems (agricultural ones); E.O. Wilson’s assertion of biophilia has gained recognition and therefore threats to biodiversity are being curbed.
Habitat loss also occurs overtime, for example, the clearing of the tropical rain forest in the state of Veracruz (Mexico) for cattle ranching has resulted in the loss of ~91% of the original forest, leaving a fragmented array of small forest islands. Dams built by humans also destroy freshwater habitats. Besides overexploitation that is deliberate, humans have unknowingly introduced species that harm the native ones or vice versa. For example, when the North American rainbow trout was introduced to Europe, the rainbow trout suffered whirling disease caused by a parasite carried by the European brown trout, and soon the disease spread throughout other parts of the world. For plants, the Asian salt-cedar and the Russian olive are two that have formed new forests and replaced native plants along rivers in the west, harmful to many bird species. Therefore, before introducing a species, precaution are now taken, since 40% of extinctions are caused by introduced species. (Source: http://www.gcrio.org/CONSEQUENCES/vol2no2/article2.html)
Sources: Campbell and Coyne books
Internet source: http://www.gcrio.org/CONSEQUENCES/vol2no2/article2.html
Humans are realizing the damage that they have done because of the growing importance of trade and transportation in the globalizing economy. With many species becoming endangered or even extinct, people are taking action to prevent this. Efforts such as reducing pollution and carbon footprint are all important, but one of the biggest factors today is knowledge. Without understanding how many species are put in danger, such as their native habitat, their natural predators, or their food source, people will be unable to help these fragile species from extinction.
ReplyDeleteEfforts such as restoring used mines with bacteria, replanting trees, and removing invasive species are all ways that humans are working to save the native and endangered species that they have now.
Today, there are many conservation efforts as a response to many of the extinctions that are occurring today. Introduction of invasive species such as Asian carp, which are slowly invading into the great lakes despite many efforts to prevent it. These bottom feeders eat plankton, which takes out the the food supply for the primary consumers and those following them like bluegills or bass. Other examples such as the rocky mountain pine beetles have devastated entire forests due to their fast reproductive rates and the native trees lack of defenses.
I have noticed that many of the responses to the question at hand focus on how humans will fix the environment--but for whom? In the end, many of these conservation efforts, smart cars, prevention of introduced species are for the benefit of humankind. There is a growing movement today known as Deep ecology. In deep ecology, the main theme isn't about restoring forests so lumber mills can get work, or reducing invasive species b/c they are harming agriculture or transportation. While these things are important, the existence of these endangered and at risk organisms isn't just to provide new medicine or to become our exotic pets. To save the environment, and understanding--a connection--with the biosphere is necessary. Other species aren't merely tools for human survival, we are all meshed together in the web known as Biophilia.
Sources:
biology book
http://www.transitionsabroad.com/listings/travel/responsible/articles/preservation-engangered-species-ecosystems.shtml
http://www.epa.gov/glnpo/invasive/asiancarp/
http://en.wikipedia.org/wiki/Deep_ecology
Humans are going to great lengths in trying to preserve the planet and its inhabitants. Conservation biologists are applying their understanding of the community, ecosystem, and landscape dynamics in established protected areas to slow biodiversity loss. For instance, “governments have set aside about 7% of the world’s land in various forms of reserves” (Campbell 1257). This is an attempt to preserve some of the land and ensure its complete survival in the future. Another attempt to preserve the land is a zoned reserve, or “an extensive region that includes areas relatively undisturbed by humans surrounded by areas that have been changed by human activity and are used for economic gain” (Campbell 1258). The key challenge of this is to develop a climate in the surrounding lands that is compatible with the long-term viability of the core that is in the process of being protected (Zoning). Also, scientists are trying to detoxify polluted ecosystems with the use of organisms (usually prokaryotes such as fungi or plants) in a process called bioremediation. This is a very natural and organic way to clean the environment and is quite effective in cleaning some soil and water (Bioremediation). Lastly, environmentalists are clearly trying to spread the knowledge about the need to protect the environment with popular slogans such as “Go Green” and phrases like “Reduce-Reuse-Recycle.” These colloquial sayings might seem very insignificant, but when added each person puts in the effort, there might be a significant impact on the environment.
ReplyDeleteLike Coyne stated, and Mary reinforced, the “distribution of life on earth reflects a blend of chance and lawfulness” (Coyne 109). The dispersal of plants and animals depends on unpredictable vagaries such as winds, weather, and the ability to live together, and also upon time and chance and organisms’ adjustment to environmental niches. When humans bring over organisms into habitats differing from their original one, negative consequences can occur. These organisms are called introduced species, and as Campbell notes, they are “exotic species that humans move, either intentionally or accidentally, from the species’ native locations to new geographic regions” (Campbell 1249). Humans can cause this species transfer in several ways, including by ship, or airplane when they travel. Some introduced species can gain a foothold in their new environment, and this often results in them preying on native organisms or outcompeting them for resources. This could create massive problems for the new environment. For instance, just like Ryan mentioned, the brown tree snake was accidentally introduced to the island of Guam as a “stowaway” in military cargo after World War II. Since then, its presence has contributed to 12 species of birds and 6 species of lizards that have become extinct on Guam because of the snake’s preying on them (USDA). Another example of an invasive species is the zebra mussel, which was introduced into the Great Lakes of North America. They clogged threatened native aquatic species and also clogged water intake structures, disrupting many domestic and commercial water supplies and causing billions of dollars in damage (GLIN). Clearly, introduced species can sometimes lead to very fatal and unfortunate effects, regardless of whether they were brought into an environment for a specific purpose or simply by mishap. Either way, the new species “aren’t good at coexisting with others” (Coyne 110) and this, like Tianyu touched upon, leads to serious problems and hinders the evolution process as whole populations unfortunately become wiped out.
http://www.invasivespeciesinfo.gov/animals/bts.shtml (USDA)
http://en.wikipedia.org/wiki/Zoning (Zoning)
http://water.usgs.gov/wid/html/bioremed.html (Bioremediation)
http://www.great-lakes.net/envt/flora-fauna/invasive/zebra.html (GLIN)