Advantages of GMO’s
The mapping of genetic material for GMO crops increased knowledge of genetic alterations and introduced the ability to enhance genes in crops to make them more advantageous for human consumption and production (Whitman, 2000). For example, plants can be engineered to be temperature resistant or produce higher yields. This provides greater genetic diversity in different regions where climate limits productivity.
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High Yield Crops

Another good reason to have GMO crops planted is to add nutritional value to crops that lack necessary vitamins and nutrients. There are areas around the world that rely on rice or corn crops, and other plant genes may be added to the crop to increase the nutritional value of that food. This will help malnourished populations receive more nutrients from their diet (Bouis, 2007). We have already made pesticide resistant plants so that farmers can use the right kinds of pesticides to rid insects and not inhibit plant growth. This will increase crop yield in two ways; there will be fewer insects and pests to eat the crops, and they will grow without being bothered by pesticides.

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Farmers spraying pesticides to GMO crops

Disadvantages of GMO's
The GMO process includes adding new genetic material into an organism's genome (Cohen, et al. 1973).In agricultural ecology, similar to bacterial genetic engineering, this means introducing new genes in the genome of crops like corn. Experimental plantings of GMO crops began in Canada and the U.S. in the 1980’s. The first time it became large scale (commercial) cultivation was in the mid 1990’s. Research on the effects of large scale cultivation of GM crops sparked various concerns. These ideas are brought up in different research studies conducted on ecosystems with GMO strains. GMO strains have the potential to change our agriculture.
A plant with unwanted or residual effects that might remain in the soil for extended periods of time (Morrissey, 2002). European Union agricultural regulators were alerted by Morrissey’s research that GM strains from GM crops remained in the soil for years after the crop was removed. Data reported that despite the absence of the GM plant, the strain persisted for up to six years.
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Soil samples showed GM strains persisted in soil for years.

Engineered plants can act as mediators to transfer genes to wild plants and then create weeds (Carstens, 2010). To keep these new weeds under control scientists invented new GMO weed herbicides that were not necessary for non GMO weeds. These chemicals are toxic to various amphibians and mammals, such as cows feeding on GMO crops. In vivo tests shows that the uptake of herbicides has toxic consequences on certain organisms (Carsten, 2011). The consequences of chemicals in aquatic ecosystems is outlined in detail in the Ecological Effects Page.
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New genetically engineered plant (weed) due to cross pollination between GM plant and non GM plant.

There is opposition in the introduction of GM genes on genetic diversity. The GM genes from crops can spread to organic farm crops and threaten crop diversity in agriculture. If crop diversity decreases, this affects the entire ecosystem and impact the population dynamics of other organisms (Williamson ,1992). The chance that one genetically modified crop strain could pollinate an already existant “non-GM” crop is unlikely and unpredictable. There are many conditions that must be met for cross pollination to occur. However, when a large scale plantation releases a GM strain during pollination, this risk increases. The cross pollination to non-GM plants could create a hybrid strain, which means there is a greater possibility of ecological novelty, or new artificial strains being introduced into the environment that could potentially reduce biodiversity through competition.
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Cows can eat GM crops and suffer side effects.

How Can We Test for GMO Safety?
~Using Bioluminescent Signals~
Whole-cell bioreporters can be used to determine toxicity or other damaging conditions in the environment. They give off fluorescent or bioluminescent signals, but are poorly tested in the environment. If found effective outside of the lab, these bioreporters would be an excellent way to test aquatic environments for adverse effects of genetically modified organisms (Tingting, et. al., 2012).
~Looking at Genes and their Function in the Environment~
When looking at risk assessment and testing, it is important to focus on the “functionality of a transgene with regard to physiological as well as ecological relations” (Breckling, 2011).
Risks that are assessed for include:
Horizontal gene transferVertical gene transferPersistanceHybridizatoinEffects of food chains in ecosystems and alterations in biodiversityIndirect effects (agricultural risks)
Used two ways to test
      • Bottom-up perspective (necessary to understand the small-scale interactions and work their way to the large-scale interactions)
      • Top-down perspective (analyze the extent the relevant factors driving the model varied in the wider context)


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Fig. 1. The up-scaling approach as it combines large-scale and small-scaleinformation. Bottom-up data input was used to model local dynamics. General knowledge on the specific crop and information from field testing was incorporated on this level. In a top-down approach, the regional variation in driving forces was analysed and used to specify scenario sets to run the model under different input conditions. The up-scaling was then achieved by selecting the model output matching the specific sites that make up the regional context. Since the model contained processes like small-scale dispersal, seed bank development and crosscontamination of fields, regional statements on the relevance of these processes on larger scale could be derived (Breckling, 2011).