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Alien Invasion
 
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ANSWERS

The Silence of the Birds

1.

The birds evolved in the absence of predators and therefore evolved no escape or defense mechanisms, such as flight or fear.


2.


C

Green Invader
  3.

Fragments from one plant can quickly grow into new ones;
No natural predators;
Built-in toxins ward off any new predators;
It blocks sunlight, killing its competition.

 
4.


Transporting fragments on ships' anchors and fishing nets;
Accidental release from private and public aquariums.

  5. B
The Silken Tree Eaters
  6.

A

 
7.

Introduced parasitic flies turned out to prefer native caterpillars to gypsy moth caterpillars, destroying native moth populations while having little affect on the gypsy moth.
Dust Busting
  8.

D

 
9.


Clearing of land for farming.

  10.

Increased incidence of asthma in Caribbean people.

     


NOTE: Quizzes with 100% correct answers can be entered by teachers only into our T-shirt drawing. FRONTIERS randomly selects 20 names after each program. Send all correct quizzes in one envelope, along with teacher's name, grade and course, school name and address, where the students watched the show (home or school), and the students' favorite segment. Mail to: FRONTIERS Quiz, Chedd-Angier Production Company, 70 Coolidge Hill Rd., Watertown, MA 02472.


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