Here in the United States, before agricultural activities
destroyed the natural balance, there were great migrations of Rocky Mountain locusts (Melanoplus spretus). Great migrating hordes of these insects once
darkened the skies on the plains east of the Rockies where crops were often
destroyed; the worst years were those from 1874 to 1877.
One of these migrating swarms was estimated to contain
124 billion locusts. During another migration in Nebraska it was estimated that
the swarm of locusts averaged half a mile high and was 100 miles wide and 300
miles long. Usually, these swarms take oft from the ground against the wind,
but, once airborne, they turn and fly with it. warm convection currents help to
lift them, often to great heights. During the great locust plagues the
situation in Nebraska became so serious that the original state constitution
had to be rewritten to take care of the economic problems. The new document was
known as "The Grasshopper Constitution." It is now believed that
these locusts were a migratory form or phase of the lesser migratory locust,
which is still common there. In this respect, the North American migratory
locusts resemble their African relatives. In both regions the migratory forms
arise as a result of crowding and climatic factors. Migratory forms are
apparently natural adaptations which bring about dispersal when locust
populations become too crowded. Fortunately for our farmers the migratory form
- - the so-called spretus species - - no longer seems to occur regularly,
although there was a serious outbreak as late as 1938 in mid-western United
States and Canada. Actually, there is no reason why the destructive migratory
form might not again appear if circumstances should become favorable.
Questions
1. Which of the following is the best title for the
passage?
(A) The Life Cycle of Locusts
(B) Migratory Locusts in the United States
(C) Locust Plagues in Nebraska
(D The Reproductive Capability of the
Locust
2. According to the passage the worst destruction by
locusts in the plains area east of the Rockies occurred during the
(A) eighteenth century
(B) early nineteenth century
(C) late nineteenth century
(D) twentieth century
3. One of the migrating swarms mentioned in the passage
averaged how many miles in length
(A) 100
(B) 124
(C) 187
(D) 300
4. It can be inferred from the passage that the state
constitution of Nebraska was rewritten in order to
(A) make the constitution more understandable to the
public
(B) encourage farmers to leave the state
(C) solve difficulties that resulted from loss of crops
(D) provide for a regular census of the locust population
5. According the passage, North American and African
migratory locusts are similar in that
(A) they always travel toward mountainous
regions
(B) their destructive activities occur only
in plains areas
(C) climates affect their development
(D) they are both mentioned in state constitutions
6. Which of the following is NOT mentioned in the passage
as influencing the migration of locusts?
(A) Darkness
(B) Agricultural activities
(C) Warm air currents
(D) Overcrowding
7. The passage supports which of the following
conclusions?
(A) the outbreak of locusts in 1938 was more serious
than any other in history.
(B) Nebraska farmers had no locust problems in the years
1874 - 1877.
(C) There is a possibility that crops in the United
States might be destroyed by locusts in the future.
(D)There is a chance that African migratory locusts may
make their way to the United States.
Please tally your answer with the below provided answers and
then comment here how much you got!
Answers
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