Informational Texts
Tiny Creatures
The Life-Giving Parasite
Have you ever been swimming in a pond, stream, or lake and had a leech stick on you? You probably thought (or shouted) “Ick!” and tried to pry it off as fast as you could, but leeches aren’t really disgusting, and sometimes they can save lives!
In ancient Egypt and later in medieval Europe, doctors put leeches on patients. They believed that the spineless wormlike creatures could cure all sorts of illnesses by sucking a patient’s blood. In Europe and in the United States, millions of leeches were used throughout the 1800s. Doctors applied leeches to treat a variety of illnesses, from obesity to headaches. People soon learned that leeches could not cure most diseases and were not a good treatment for patients. However, in 1985, a Harvard University doctor changed people’s thinking once again. He was trying to reattach a patient’s ear, which had been cut off. He had trouble reconnecting the veins because the patient’s blood kept clotting. He applied a leech to draw out the blood and saved the ear.
Since then, leeches have often been used in surgery where body parts are reattached. During surgery, a leech is placed on the area where the surgeon does not want blood to pool and clot. Then the leech secretes a substance that keeps the veins open and stops the blood from clotting. The leech sucks up excess blood, allowing fresh blood to flow, which helps the patient heal.
Some people are horrified at the thought of having a bloodsucking creature attached to them, but why not welcome a leech if it can save your life?
Have you ever been swimming in a pond, stream, or lake and had a leech stick on you? You probably thought (or shouted) “Ick!” and tried to pry it off as fast as you could, but leeches aren’t really disgusting, and sometimes they can save lives!
In ancient Egypt and later in medieval Europe, doctors put leeches on patients. They believed that the spineless wormlike creatures could cure all sorts of illnesses by sucking a patient’s blood. In Europe and in the United States, millions of leeches were used throughout the 1800s. Doctors applied leeches to treat a variety of illnesses, from obesity to headaches. People soon learned that leeches could not cure most diseases and were not a good treatment for patients. However, in 1985, a Harvard University doctor changed people’s thinking once again. He was trying to reattach a patient’s ear, which had been cut off. He had trouble reconnecting the veins because the patient’s blood kept clotting. He applied a leech to draw out the blood and saved the ear.
Since then, leeches have often been used in surgery where body parts are reattached. During surgery, a leech is placed on the area where the surgeon does not want blood to pool and clot. Then the leech secretes a substance that keeps the veins open and stops the blood from clotting. The leech sucks up excess blood, allowing fresh blood to flow, which helps the patient heal.
Some people are horrified at the thought of having a bloodsucking creature attached to them, but why not welcome a leech if it can save your life?
Not-So-Tiny Creatures
Florida’s Python Problem
Sometimes pets are more than we can handle, like when a small puppy grows up to be a huge dog. People can usually find a new home for a big dog, but a giant pet snake is not so easy to give away. As a result, some people in Florida have released their pet pythons into the wilderness of the Florida Everglades. Problem solved? Only for the pet owners.
The snakes that are the biggest problem are Burmese pythons. These snakes are not native to the Everglades. Pet dealers originally brought them to the United States from Southeast Asia. Because Burmese pythons are not native, they disrupt the natural order of the Everglades’ ecosystem.
The snakes’ size and strength are also a problem. Burmese pythons can grow to be 20 feet long. There are reports of terrifying battles between pythons and alligators in the Everglades. Even more worrisome is the impact on creatures that are no match for the monster snakes. For example, biologists have discovered endangered birds, bobcats, and woodrats in pythons’ stomachs.
Another effect of python dumping is the spread of these snakes beyond the Everglades. Pythons swim well and can move more than a mile a day on land. In addition, one snake can produce nearly 100 eggs. Their wide range of movement and high rate of birth means that the snakes can quickly overrun a habitat.
As a result of this scary scenario, Florida park rangers, wildlife officials, and others are on “python patrol.” They capture and kill Burmese pythons to try to keep the numbers under control. There is also a greater effort to teach people about the responsibilities of keeping a python.
The Snake That's Eating FloridaClassroom Code: hornsby2015
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