"Bloodsucking insects are frightening to people and cause a great deal of anxiety. They creep up on you, feed on you, and then leave." - Dr. Gale Ridge, Connecticut Agricultural Experiment Station (CAES)
"At first glance, these creatures are bizarre and horrible looking, but they’re in fact quite innocuous for the most part and they form a natural part of our environment." - Dr. Leonard Munstermann, entomologist and museum curator.
With more than one million known species, insects represent the most diverse and predominant life form on planet earth. It is natural to fear being the victim of a bloodsucking insect and the possibility of contracting disease, but far less than 1% of all insects feed on the blood of humans and other vertebrate animals. If we can get beyond our phobias, we’ll find that these creatures are truly fascinating.
In this exhibit, we focus on five types of bloodsucking insects: fleas, lice, bedbugs, mosquitoes, and ticks. Ticks, though not true insects, also use blood in a similar way.
Fleas are the bane of our pets’ existence. Lice thrive on our skin and hair habitat. Bedbugs are uninvited nighttime companions. Ticks consume large amounts of blood to produce eggs and can carry infectious bacteria causing Lyme disease. Mosquitoes, whose humming is the soundtrack to our summers, have been linked to recent outbreaks of the West Nile Virus. So, one might ask, are these blood feeders a great danger to us all?
"Ninety-nine chances out of one hundred, if a mosquito feeds on you, you are not going to have any serious problems other than perhaps a localized itchy spot. A mosquito bite is really more interesting than it is harmful." - Dr. Munstermann
"Bloodsucking insects are intriguing in that they have the ability to take a shortcut in their dietary habits. All the hunting for food has already been done for them, and all the digestion of the food has been done for them, and is served up to them in a blood buffet. They have evolved to capitalize on other people’s or other animals’ efforts to survive and they just tap into it by feeding on the blood." - Dr. Ridge
Ticks, lice, fleas, mosquitoes, and bedbugs each have a distinct body structure and evolution, but they all share the same feeding strategy. Find a warm-blooded vertebrate, like us humans, and suck blood.
"These blood meals of course serve a really important biological function for the insect. The protein in the blood is essential for the development of the eggs." - Dr. Munstermann
"It expedites and cuts out a lot of the energy effort to get that nutrition by having a direct blood meal." Dr. Ridge
In order to locate and gain access to their favorite foodstuff, bloodsuckers have evolved highly sophisticated tools. The mosquito, for instance, has an apparatus for sensing the carbon dioxide we breathe and another for sensing the heat we emit.
"Once it lands on the host, then it has another whole set of sensors to find an appropriate place to begin the penetration and once it finds that spot, then the knives and scissors come into play. And it has knives that are extremely small, but they are very efficient in cutting through those layers of protein that form the surface of your skin and they cut in." Dr. Munstermann
"They want to be stealth feeders; they come in feed, and get out. It’s like a drive-through feeding session. Get the blood and go, because the last thing any of these bloodsuckers particularly want is for you to hit them."
"This insect has been very intimate in man’s existence on this planet for thousands of years. During the period of the last ice age in the East Mediterranean zone in the mountains, peoples migrated into caves and, of course, who was living with them but bats. And so bats had this problem with the bedbug and then these populations crossed over and started to feed on people."
"You can see bedbugs distributing across the world following the trade routes, to the east, then up into Europe. And, of course, they came along with the Pilgrims and arrived in the Americas. Their history is our history following us along." - Dr. Ridge
As seen with the bedbug, insects, particularly blood feeding insects, have a longstanding, ongoing relationship with human beings. In fact, these creatures have a long evolutionary history, living on earth since the time of the dinosaurs and adapting to new host species over time.
"These things are just simple little insects doing their job, their daily job or their nightly job, and people should not be afraid of them." - Dr. Ridge
Feeding on meals of blood, these amazing creatures deserve our fascination more than our fear.
The Yale Peabody Museum of Natural History gratefully acknowledges the following principal sponsors for their contribution and support to the Biodiversity and Human Health Program entitled Curricula modeled on biodiversity and vector-borne disease:
Science Education Partnership Award (SEPA) from the National Center for Research Resources (NCRR) of the National Institutes of Health (NIH).
Produced by Ann Johnson Prum.