Key Concepts
Question of the Day
Is the Mosquito of value to mankind?
Lesson of the Day
There are 3,500 named species of mosquitoes in the world, most of which do not bother humans in any way. However, a few hundred species do bite humans, and in doing so can be the vector for a variety of serious illnesses such as Yellow Fever, Dengue Fever, Japanese encephalitis, Rift Valley fever, Chikungunya Virus, West Nile Virus, and Malaria which infects 247 million people worldwide each year, and kills nearly 1 million.
Dating back almost 100 years humans have made repeated and concerted efforts to eradicate mosquitoes. In certain cases such efforts have resulted in positive outcomes, such as the elimination of malaria from the United States in 1949. Most campaigns however, have been unsuccessful. Historically, little thought was given to the implications of eradicating an organism such as the mosquito. However with a growing understanding of the function of ecosystems even the lowly mosquito is now recognized as having merit. Mosquitoes, both in the form of water dwelling larva and as winged insects, form a significant biomass in the world and serve as a rich source of food for many fish and birds, not to mention the function they serve pollinating thousands of plant species. The sudden elimination of mosquitoes could result in many hungry animals and many un-pollinated plants. Although experts are uncertain of the impact the global eradication of mosquitoes would have on ecosystems, it is important to understand that even the mosquito, considered at best a pest, has an important role in a healthy ecosystem.
The question of whether mosquitos provide ecosystem services to mankind is less clear. Certainly they have a negative impact on humanity as a vector of disease that drives huge cost and suffering annually. But is this offset by positive services?
Indirectly the elimination of the mosquito could have a significant negative impact on human beings by destabilizing fish and bird species that rely on the mosquito as a food source. For instance the mosquitofish is a specialized predator that feeds almost exclusively on mosquito larva, that could go extinct with the eradication of the mosquito, resulting in a chain reaction up and down the foodchain that could impact human beings. The same could hold true for many species of insect, spider, salamander, lizard and frog that rely on the mosquito as a primary food source. As pollinators mosquitos service thousands of plant species but not any crops on which humans depend.
So is the mosquito have value for mankind? There is not a simple yes or no answer to this question. Ecosystems are complex networks of inter-reliant life forms and environmental factors, and mosquitos play a significant role in ecosystems world-wide. What the impact eradication of the mosquito would have on ecosystem services is unclear, and we will not likely ever know as the mosquito appears to be here to stay.
Words to Run By
Today you are heading back into the rainforest where doubtless you will encounter a mosquito or two. There are 3,500 named species of mosquitoes in the world, most of which do not bother humans in any way. However, a few hundred species do bite humans, and in doing so can be the vector for a variety of serious illnesses such as Yellow Fever, Dengue Fever, Japanese encephalitis, RiL Valley fever, Chikungunya Virus, West Nile Virus, and Malaria which infects 247 million people worldwide each year, and kills nearly 1 million. We are all taking anD-malarial medication here in the Amazon.
It is probably safe to say few people have much good to say about mosquitoes. DaDng back almost 100 years humans have made repeated and concerted efforts to eradicate mosquitoes from the globe.
The question I want you to consider today is:
Is the Mosquito of value to mankind?
Daily Dispatch
The morning started with a chorus of howler monkeys, a guttural yowl from the canopy above; two competing groups filling the air with a rhythmic resonance sounding like a four-stroke motor married to a dijereedoo. The Youth Ambassadors were asked to catch live mosquitoes in the jungle today. This is not as easy a proposition as one might imagine. All thought the jungle would be teaming with biting insects, but mosquitoes have been shy partners. One can comfortably walk through this jungle in shorts and a tee-shirt. Scouting along the trail the Youth Ambassadors found a rubber tree, elastic sap clinging to the bark. Their guide Jose explained that the rubber trade between1890 and 1910 had decimated the aboriginal population of the Amazon, leaving a permanent distrust of white men. Rubber traders scoured the jungles of Peru enslaving local people, and murdering them or their loved ones if they did not deliver a regular ransom of rubber sap. The Peruvian Nobel laureate Mario Vargas Ilosa, has written of this genocidal moment in history. After some effort mosquitos were caught, and a sample of stagnant jungle pond water obtained to look for larva. For over one hundred years man has been trying to eradicate the mosquito from the face of the Earth, but without success. Although devalued by humanity, mosquitoes contribute meaningfully to the food chain, and are important pollinators of plants.
Video of the Day
» Zapped: The Buzz About Mosquitoes
Photo of the Day
Coming soon.
Expert Video
School Activities
Coming soon.
Youth Ambassador Activity
The Youth Ambassadors will trace the life-cycle of the mosquito. They will collect mosquito larva from standing water and catch mosquitos in mosquito traps.
They will consider how mosquitos interact with human beings. They will consider the following questions:
Links
http://www.nature.com/news/2010/100721/full/466432a.html
http://blogs.cornell.edu/bioee1610/2011/09/25/a-world-without-mosquitoes/