Name ______
Alien Invasion
If there is an insect that looks like it belongs in a Star Wars movie, the Asian long-horned beetle fits the bill.
The inch-long insect is a glossy black-and-white bug with antennae twice as long as its body. Like Darth Vader and the Forces of the Dark Side, the Asian long-horned beetle is a menace. The beetles don't attack humans, but their larvae, or grubs, munch on the insides of living trees until the trees weaken and die.
The beetles were first spotted in Brooklyn, N.Y., in 1996. Today, they destroy thousands of maple and poplar trees every year. The Asian long-horned beetles are now one of several invasive species that pose a serious threat to the environment of the United States.
All Shapes and Sizes
An invasive species is a plant, an insect, or an animal from another country that doesn't belong in the United States. The species usually don't have natural enemies to keep their population under control. Some were brought here on purpose, others by accident.
These alien critters come in all forms. Consider these:
- Red imported fire ants:
These plant-chewing ants arrived in the United States in the 1930s on ships from South America. The ants are known to use their powerful jaws and burning sting to kill young animals and destroy all types of crops.
- Africanized honeybees:
Colonies of the so-called killer bees began swarming into Texas from Mexico in 1990. The bees can be dangerous because they attack in numbers. The bees have killed more than 1,000 people since first being imported from Africa to Brazil in 1956.
- Nutrias:
These furry, swamp-dwelling rodents look like 10-pound rats with clawlike feet. They were brought to the United States from South America in 1899 for their fur. Today, nutrias are devouring plants and overrunning wetlands in Louisiana, where state wildlife officials offer hunters $4 a head to kill the annoying varmints.
- Zebra mussels:
Originally found in Russia, zebra mussels were discovered in the Great Lakes in 1988. A female zebra mussel can produce a million eggs a year. With voracious appetites, the mussels can suck the food supply out of a freshwater lake, leaving nothing for native species to eat. The tiny mussels also clog pipes and cling to boat hulls and docks.
A Walking Fish!
Last summer, biologists in Maryland had to kill alien fish before the fish caused too much trouble. Although native to China, the meat-eating snakeheads were thriving in a pond in that state.
Snakeheads grow to 3 feet long and use their sawlike teeth to chomp down on insects, frogs, aquatic birds, and other fish that get in their way. The snakeheads use such bully tactics to take over rivers and lakes.
Snakeheads even use their front fins to "walk" on land. They can survive up to three days out of water by breathing through their mouths as well as their gills.
Federal and state wildlife officials in Maryland worried that the fearsome fish would eventually spread to other bodies of water. "If the [snakeheads] get into the river, you'll never get rid of them," one freshwater fish expert said.
Government scientists quickly solved the problem. They used poles to send electric currents into the pond, stunning and killing the nasty snakeheads.
How Did They Get Here?
Invasive species don't magically appear. Often humans are the source of the problem. For example, a local resident was responsible for buying two live snakeheads at a fish market and later releasing them into the Maryland pond. The fish bred like crazy until being discovered.
Sometimes getting rid of the alien animals or insects is not easy; in fact, it can be downright destructive. The only way to stop the Asian long-horned beetle from taking over is to cut down infested trees, then chop and burn the wood-with the pesky beetles inside.
"All of humanity is together in fighting this," said Henry Stern, New York City's former parks commissioner.
Citation: "Alien Invasion." Weekly Reader Senior, 17January2003. Facts for Learning
Write a sentence or two that sums up the main idea of the passage (What? and SoWhat?)
______
______
What is the main pint of this passage?
AThe Asian log-horned beetle destroys thousands of trees every year.
BInvasive species pose a serious threat to the environment of the United States.
CHumans are to blame for introducing invasive species, such as snakeheads, into our environment.
DInvasive species come in all forms.
Pluto
You probably know the names of all the planets in the solar system - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. Well, that list may not be right. A growing number of scientists are saying Pluto is not a planet.
Pluto is the smallest planet in our solar system, and the only planet made of ice. Pluto is located in an outlying area of the solar system known as the Kuiper (KOY-per) belt.
Scientists have discovered about 400 objects in the Kuiper belt but think millions of objects may be located there. All of the known objects in the belt are made of ice, including Pluto.
Some of the other Kuiper belt objects are almost as large as Pluto is. Varuna, which scientists discovered last year, is about 40 percent the size of pip-squeak Pluto.
Scientist Brian Marsden is one of many scientists who say Pluto is not a planet. He argues that if Pluto had been discovered last week, it probably would not have been classified as a planet. "[Pluto is] still an interesting object," said Marsden. "It's just that it's an interesting member of the Kuiper belt [and not a planet]."
Citation: "Is Pluto a Puny Planet?." Science Spin Senior, September 2001. Facts for Learning
Another possible title for this article is
A“The Smallest Planet’
B“A Member of the Kuiper Belt”
C‘What Are the Names of the Planets?”
D“Is Pluto a Planet?”
Main Idea