¶ … Gitig, D. (2017). A farewell to kings? New ideas on the vanishing monarch butterflies. Ars Technica. April 30, 2017. Retrieved online: https://arstechnica.com/science/2017/04/a-migrating-butterfly-a-poisonous-plant-and-their-remarkable-coevolution/ In this article, Gitig (2017) provides an overview of recent research on monarch butterflies, focusing on the causes of their diminishing populations. Monarch butterflies feed almost exclusively on a plant called milkweed. Milkweed is disappearing rapidly due to urban development and other human activities. Therefore, the monarch butterflies have less to eat and this may be the direct cause for their dwindling numbers. In fact, adult monarch butterflies do not just feed on milkweed but also lay the next generation of eggs on the plant. The milkweed plant actually perceives the monarch as a parasite and emits latex to trap and kill the monarch caterpillars. Only about 10% of monarch eggs make it to become fully formed butterflies, according to the author. The most remarkable aspect of the monarch-milkweed relationship is that the surviving monarch caterpillars assimilate the toxic cardenolides from the milkweed latex by transforming those chemicals into color patterns in their butterfly wings. The chemical process is called aposematic coloration. The aposematic coloration gives the butterflies their unique appearance and also warns off potential predators, especially birds. Therefore, the monarchs benefit from the milkweed's defensive...
Gitig (2017) also discusses the potential causes for disappearing monarchs throughout their habitats in North America. Possible causes include habitat loss and drought conditions, but there is no one absolute cause for the dwindling numbers of monarchs.
In 2005, the average population density was 89 persons per square mile, and the majority of the population is located in southern California, the San Francisco Bay area, and the Central Valley (MSN Encarta, 2006). The sections below examine the geographical patterns of California in relation to the issue of urban encroachment. Literature Review Many researchers have studies the historical patterns of agriculture in California and have determined that it's loss
Therefore, strong educational campaigns are absolutely essential in the successful execution of urban ecological advocacy programs. One of the most fundamental efforts that come from NOAA funding is that of educational campaigns. Along with sponsoring coastal cleanups, NOAA is a prime example of a government agency focusing on recycling education campaigns within Miami-Dade's most populated areas, like the area surrounding Brickell Ave. Educating the public in terms of recycling
The more jobs that can be created with this money, the more people that can get back to work and the money people that can get on with their lives. And that is exactly what the people of New York City want to do. Works Cited Hill, Jeffery. "What the Stimulus Bill Really Means for Cities." 2009. Next American City. 7 June 2009 http://www.liu.edu/cwis/cwp/library/workshop/citmla.htm "House Passes Stimulus Package; Rep. Michael E. McMahon Secures
Urban Sprawl is a problem that can have severe consequences for all life if the continuing expansion of developed landscape is left unrestricted. The unrestricted development of the United States and the world is rapidly contributing to the degradation of our ecosystem. Moreover, if over development continues there will be massive human suffering. Air and water quality are in jeopardy and topsoil is being lost at an alarming rate. If
Urban sprawl is not something that too many people really seem to spend that much time thinking about. Despite this, however, many people do have to deal with it. Those that are faced with the problem are often unsure about what they should be doing about it, and those that work in the field of trying to control it often struggle between making sure that there are enough places for
If there is an aggregate sub-base, these can provide water quality treatment. There should be good compaction and appropriate geo-textiles especially for areas accessible to heavy vehicles. Permeable pavements reduce the need for deep excavations thereby providing a cost benefit. This system reduces the run-off rates and peak flow. The overall benefit is that it removes pollutants and holds water so that it does enter the main drainage. A lot
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