Tag Archives: proboscis

Our blood too rich

mosquito_cropped

I choose today, when most of us in New England are sunk under wet snow and dreaming of the hot, humid days of summer, to remind you that every season has its dark side.  When the sun is beating down on us and moisture in the air suppresses our every movement, we will fall prey to a ubiquitous pest that everyone recognizes: the mosquito.  Last year’s wet spring left plenty of standing water for breeding, and the resulting swarms were, in some places, intolerable.  But why do these insects behave the way they do?  How do they find us?  Why do they require our blood?

First came the scouts who felt our sweat in the air
and understood our need to make a sacrifice.  
 
We were so large and burdened with all we had carried
our blood too rich for our own good.  
 

Alison Hawthorne Deming’s poem, “Mosquitoes,” examines the interaction between mosquitoes and humans in a slightly different viewpoint than we are used to.  Most often, humans view mosquitoes as pests, disease-bearing annoyances that inhibit our enjoyment of the outdoors in summer.  Instead, the speaker in this poem views us as a sacrifice, burdened with rich blood ripe for the taking.

There are over 2,700 species of mosquitoes in the world, and all of them require water to breed.  Most eggs overwinter and hatch into larvae in the spring.  Larvae eventually grow into pupae, which after one to four days form a pupal case, within which they metamorphose into adult mosquitoes.  Their purpose now is to mate and feed.

Female mosquitoes are the attackers.  (Males live only a few days after mating, surviving on plant nectar.)  Protein obtained from ingesting blood aides the female in development of eggs.  The mosquito requires a blood meal each time she lays eggs, and can live anywhere from days to weeks, repeating the process of feeding and laying eggs many times.  The eggs hatch or overwinter; the cycle resumes.

Then came the throng encircling our heads like acoustic haloes
droning with the me-me-me of appetite.
 

Several factors have been shown to attract mosquitoes, including: perspiration, heat, light, body odor, lactic acid, and carbon dioxide.  When a female lands on a likely victim, she sucks blood with her proboscis, or feeding apparatus.  There are actually six mouthparts contained in the female’s needle-like proboscis.  The outer sheath is the labium, which bends back to allow the two pointed mandibles and two serrated maxillae to penetrate the skin.  Mosquito bites are generally not very painful because the jagged shape of the maxillae results in a low surface area and a minimum of contact with nerves in the skin.  On the basis of this finding, a Japanese scientist has recently designed a nearly-painless hypodermic needle modeled after a mosquito’s maxilla.

Once the maxillae and mandibles have entered the skin, the mosquito pumps her own saliva into the wound through a hypopharynx, while the tubular labrum allows her to suck blood into her own abdomen.  The saliva contains an anticoagulant, ensuring that blood flow is continuous through the meal.  Itching after a bite is due to our natural immune response to the mosquito’s saliva.  Even after the swollen wheal disappears, the itch remains until your body has broken down the proteins in the saliva.

We understood their female ardor to breed and how little
they had to go on considering the protein required to make
 
their million-fold eggs.  Vibrant, available, and hot,
we gave our flesh in selfless service to their future.  
 

So think of this as you complain about winter.  Remember that summer is coming, and with it, the mosquitoes.  Prepare yourself as a sacrifice.

REFERENCES:

Coxworth, Ben.  04.04.2011.  “Mosquito inspires near-painless hypodermic needle.”  Gizmag.com

Darsie, RF, Jr. and RA Ward.  1981.  Identification and Geographical Distribution of Mosquitoes of North America, north of Mexico.  Fresno, CA: American Mosquito Control Association.

Freudenrich, Craig.  “How Mosquitos Work.”  Howstuffworks.com

“Mosquito Biology.”  Alameda County Mosquito Abatement.  Link. 

“Mosquitoes.”  Alison Hawthorne Deming.  Read it here.

Sutherland, DJ.  2013.  “Mosquitos in Your Life.”  Rutgers School of Environmental and Biological Sciences: Department of Entomology page.  Link.