(二)
The brown widow spider became established in Southern California in early 2000 and has become part of the local spider family in urban Los Angeles and San Diego. The brown widow spider is continuing its expansion in Southern California and could possibly move northwards into Central California.
The brown widow is suspected to have evolved in Africa although it was first described from South America, which adds confusion as to where it might have originated. It is a tropical and subtropical spider having established populations in Hawaii, Florida, parts of Australia, South Africa and Japan. In North America, the brown widow was restricted for many decades to the Florida peninsula. However, around the year 2000, it started showing up in other Gulf Coast states. Brown widows are now known from Texas to Georgia and South Carolina.
The brown widow builds its web in protected sites around homes and in woody vegetation with branches. Some typical sites selected by brown widows for web building are empty containers such as buckets and nursery pots, mail boxes, entry way corners, under eaves(屋檐), storage closets and garages, undercarriages of motor vehicles that are stationary for long periods, and the undersides of outdoor furniture. They choose places that are more exposed than sites chosen by black widows and therefore appear to be at higher risk for interactions with humans as far as bites are concerned.
One recent study demonstrates that the brown widow spider is less poisonous than other widow species. The reason for the weaker effect of brown widow bites on humans is possibly because the brown widow does not have much poison as its larger relatives, but it is really a threat to humans as to its poison. The two major symptoms of a brown widow bite are that the bite hurts when it is given and it leaves a red mark. These two symptoms are not much different from the bite of normal household spiders.
There is no specific information regarding the control of brown widows by farm chemicals. Most current advice is what is used for controlling spiders in general. Therefore, most commercially available farm chemicals should work on brown widows. Avoiding a mess of the house and the garage should reduce nest sites for them. Also, one should store garage items in plastic bags where there might be interactions with spiders. These items include rarely worn garments such as gardening clothes and gloves, recreational items like sports equipment(i.e., baseball gloves) and other items where spiders can crawl up into holes where fingers can be inserted.
5.The author wrote this article to ________.
A.announce the result of a research on spiders
B.introduce the ways to get rid of the spiders
C.report a new finding of the widow species
D.warn readers against the brown widow
6.From the passage we can conclude that ________.
A.brown widows are spreading northwards
B.the brown widow originated from Africa
C.brown widows now can be found in all countries
D.there used to be no brown widows in North America
7.The third paragraph is mainly about ________.
A.the brown widow's web building
B.the characteristics of the brown widow
C.the habitat preferences of the brown widow
D.the brown widow's threat to human beings
8.It can be inferred that ________.
A.brown widows can be killed with any farm chemical
B.at present people can only control brown widow spiders
C.the brown widow has more poison than the black widow
D.victims bitten by the brown widow needn't see the doctor
