Controlling the Enemy

By: Judi Stuart
Port Discover - Visitor Services Manager

Controlling the Enemy
What creature on earth is responsible for more human deaths than any other? Maybe you’re thinking about monstrous snakes, fierce alligators, tigers, elephants, or some other powerful predator.

You may be surprised to know that many scientists credit the mosquito as being one of the most dangerous animals on earth. By virtue of their ability to carry so many potentially deadly diseases, especially malaria, the mosquito has been a formidable enemy of humankind throughout history.

Some historians list malaria as one of the factors in the downfall of the Roman Empire. The settlement of Jamestown was devastated by fever carried by mosquitoes. During World War II 500,000 soldiers were infected, causing a significant health problem among the forces.

The term malaria comes from the Italian words for “bad air” so named because it occurred near swampy areas. Later it was discovered that a species of plasmodium carried by the insect was the cause of malaria.

In this area, we joke about the size of the Hatteras mosquitoes, but these relatively small creatures are the subject of much angst throughout the world. The only place where you could escape them on earth is Antarctica.

In the world of etymology, they are known as vector organisms, which means they are agents for transmitting an infectious pathogen into another living organism. There are 3,500 species, but not all of them carry disease such as malaria, yellow fever, dengue fever, West Nile virus, and eastern equine encephalitis virus (Triple E).

In 2010, the World Health Organization reported 219 million cases of malaria and 660,000 to 1.2 million deaths from the disease that now affects forty percent of the world. Although great strides have been made since 2000 in controlling malaria worldwide, underdeveloped countries are still devastated by its occurrence among children. One out of eight children in sub-Saharan Africa dies from disease before reaching age five.

Insecticides, repellents, and insecticidal bed nets are the main means of preventing the spread of the disease. When DDT could be used as a pesticide, control of the insect led to a drop in the disease. Efforts to develop a vaccine have not been successful, but work is continuing.

In areas of the world where the disease is still prevalent, economic growth is slow and the resulting poverty makes health care and prevention unavailable to most of the population. During the late nineteenth and early twentieth century the economic progress of the American South was affect by the same cycle of disease and poverty.

In the past decade, the distribution of long lasting insecticidal nets, improved diagnostic tests, and better treatment have reduced the deaths from malaria by more than fifty percent around the world. Costs of these measures have also declined making them more available.

Global foreign aid and scientific measures being taken in this area of disease control has had a huge effect in making the world a better place for all.
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Fight or Flight?

By: Judi Stuart
Port Discover - Visitor Services Manager

FIGHT OR FLIGHT?
What makes one person able to run into a dangerous situation to help, and another be compelled to run in the opposite direction? All humans have the same biological responses to fear, but some people are able to overcome them.

It seems that we are constantly bombarded with the fears of modern living. Media informs us of the dangers of our life styles, health choices, food, cars, communities, other people, animals, and super bugs, just to name a few.

Most of us have become conditioned to those daily fears, but when events like shootings, terrorist attacks, and senseless violence happen, we begin to wonder what our own response would be if we were in those situations.

The human brain contains more than 100 billion brain cells that work together to produce autonomic responses in cases of extreme fear. We do not intentionally have physical reactions, but instead, our body responds automatically.

Several parts of the brain are involved in the fear response. The thalamus decides where to send the incoming stimuli while the sensory cortex interprets the data. The hippocampus helps to decide the context of the event and the amygdala decodes emotions and determines if there is a real threat. Finally, the hypothalamus activates the fight or flight response, if it is necessary.

There are two paths to the fear response which occur simultaneously. The low road is quick and causes a “take no chances” reaction while the high road involves more interpretation and considers the options.

Our bodies immediately react to the stress hormones like adrenalin being produced with physical signals such as our heart rate quickens, blood pressure increases, mouth dries out, pupils dilate, veins constrict sometimes causing a chill or goose bumps, and blood glucose levels rise. Smooth muscles relax to allow more oxygen into the lungs, non-essential systems like digestion shut down, and we have trouble focusing on small tasks.

Fear is essential to mankind’s survival when will and reason are powerless against danger. Early man knew that rain sometimes came with frightening thunder and lightning producing fire, so he learned to stay inside. Rational fear is manageable and keeps us from doing things like walking down a dark ally.

Studies have shown that teenagers fear such things as terror attacks, death, failure, war, being alone, and the future. New research is focusing on the fear of bullying and its short and long term effects on learning. Chronic fear can be emotionally and physically debilitating as seen in phobias.

Recent events in Boston have caused some of us to question and cope with our own levels of fear. What would be our own reaction in such a situation? Would we run to help others or would we run in the other direction? The answer lies in our ability to deal with our fight or flight response. Let’s all hope that we never need to discover the answer. President Franklin Roosevelt said, “The only thing we have to fear is fear itself.”
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Signs of Spring

By: Judi Stuart
Port Discover - Visitor Services Manager

Signs of Spring
Pansies blooming, purple martins arriving, grass getting green, buds sprouting everywhere, temperatures warming, snakes slithering by—what?--snakes? No, that’s not one of most people’s favorite harbingers of spring. Warmer days call humans to come outdoors and snakes to slither out from under their napping places.

“Sssnakes” at Port Discover’s Afterschool Science on March 28, 2013

Last week Port Discover hosted an outreach program from the North Carolina Museum of Natural Sciences. “Snakes” was the topic for the afterschool program attended by 45 students.

Our presenter brought several of her slithery friends with her and allowed the students to pet them and ask lots of questions. Her companions included a very impressive ball python, a common black rat snake, and a brown water snake which so many people mistake for a venomous water moccasin.

She told us that North Carolina has 35 species of snakes of which six are venomous. They are the eastern coral, copperhead, cottonmouth, eastern diamondback rattlesnake, timber rattlesnake and the pygmy rattlesnake.

Copperheads are found in all 100 NC counties and are responsible for 90 percent of the state’s venomous snakebites. They are edge dwellers and love ivy and the cover of rocks. They are less likely to slither away from humans than other snakes, and usually freeze in place. If you see one, the best thing to do is back away. Most snakebites happen when people are trying to kill the snake. In general, most snakes are just as afraid of you as you are of them.

My personal theory concerning wildlife is that I enjoy watching them from a distance. If they don’t bother me, I certainly won’t bother them. The problem with snakes is that they are silent and blend into their environment so well that you might come up on one without meaning to do so, thus startling both of you.

Last December in Queensland, Australia a little boy, age 3, found some eggs and wanted to keep them. His mother provided a container and let the child keep them in his room. A few days later, she found that the container was full of hatchlings of eastern brown snakes which are one of the most venomous snakes on Earth. She took the snakes to a sanctuary where they were released into the wild.

In Darwin, Australia, a daycare facility had to be closed because of an infestation of 23 baby pythons. Upon investigation, the mother and more babies were found hidden in the wall of the center. Stories like these help maintain the snake’s fearsome reputation.

Snakes are invaluable to humans because they help control such pests as rodents and insects. Scientific study is being done to discover other beneficial uses. Snake venom might be used to treat cancer and diabetes someday. The venom of the Black mamba effectively blocks pain in mice and may become an alternative to opiate drugs.

As with all wildlife, people should show respect for snakes and their place in the natural order, but keep a safe distance.
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