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Ants as a Barometer of Ecological Change
      At picnics, ants are pests. But they have their uses. In industries such as mining, farming and forestry, they can help gauge the health of the environment by just crawling around and being antsy.
It has been recognized for decades that ants¡ªwhich are highly sensitive to ecological change¡ªcan provide a near-percent barometer of the state of an ecosystem. Only certain species, for instance, will continue to thrive at a forest site that has been cleared of trees. _____(1)_____ And still others will move in and take up residence.
      By looking at which species populate a deforested area, scientists can determine how ¡°stressed¡± the land is. _____(2)_____ Ants are used simply because they are so common and comprise so many species.
      Where mine sites are being restored, for example, some ant species will recognize the stripped land more quickly than others. _____(3)_____ Australian mining company Capricorn Coal Management has been successfully using ant surveys for years to determine the rate of recovery of land that it is replanting near its German Creek mine in Queensland.
      Ant surveys also have been used with mine-site recovery projects in Africa and Brazil, where warm climates encourage dense and diverse ant populations. ¡°We found it worked extremely well there,¡± says Jonathan Majer, a professor of environmental biology. Yet the surveys are perfectly suited to climates throughout Asia, he says, because ants are so common throughout the region. As Majer puts it: ¡°That¡¯s the great thing about ants.¡±
      Ant surveys are so highly-regarded as ecological indicators that governments worldwide accept their results when assessing the environmental impact of mining and tree harvesting. _____(4)_____
      Why not? Because many companies can¡¯t afford the expense or the laboratory time needed to sift results for a comprehensive survey. The cost stems, also, from the scarcity of ant specialists. _____(5)_____

A  This allowed scientists to gauge the pace and progress of the ecological recovery.
B  Yet in other businesses, such as farming and property development, ant surveys aren¡¯t used widely.
C  Employing those people are expensive.
D  They do this by sorting the ants, counting their numbers and comparing the results with those of earlier surveys.
E  The evolution of ant species may have a strong impact on our ecosystem.
F  Others will die out for lack of food.
Stonehenge
      Stonehenge, the mysterious ring of ancient monoliths from the dawn of Britain¡¯s proud civilization, could be the work of a central European immigrant, archaeologists said not long ago in a shock statement. An early Bronze Age archer, whose grave was discovered near the stone circle last year, may have helped build the monument._____1_____Or he might have brought in a region neighboring Switzerland, such as southern Germany or western Austria.
      The archer ¡°would have been a very important person in the Stonehenge area,¡± said Andrew Fitzpatrick, Wessex Archaeology¡¯s project manager. ¡°It is fascinating to think that someone from abroad could have played an important part in the construction of Britain¡¯s most famous archaeological site. ¡±
      The 4,000-year-old man was identified as an archer because of the flint arrowheads found by his body, along with other artifacts belonging to the Beaker Culture in the Alps during the Bronze age._____2_____ though it could be coincidence that the man lived close to Stonehenge at about the time the great stones were put in place, archaeologists suspect that he was involved in constructing the monument. The archer, dubbed ¡°The king of Stonehenge¡± by the British press, lived around 2300 B.C., about the time the great stone circle was formed in Amesbury, 120 kilometers southwest of London.
      The splendid artifacts found in his grave indicated he was a man of wealth, leading archaeologists to speculate he was an important dignitary involved in the monument¡¯s creation. Stonehenge was built about the time the rich Breaker Culture came to Britain._____3_____
      4_____ He was strongly built but suffered an accident a few years before his death that severed his left knee cap. Truman said the case of death was not known, but it could have been a bone infection caused by his leg injury.
Archaeologists also found the grave of a younger man, aged 20 to 25, nearby. _____5_____ This indicated they were related and were possibly father and son. Tests on the younger man¡¯s tooth enamel showed that he grew up in Britin. The archaeologists thus speculated the archer lived in Britain for many years and had a family, and was not just passing through.

A  And tests on the chemical components of his tooth enamel showed he grew up in the region that is now known as Switzerland.
B  He and the archer shared an unusual bone structure in their feet.
C  Stonehenge will remain mysterious for many centuries to come.
D  The artifacts found in his rich grave discovered about 5 kilometers from Stonehenge indicated he was obviously a very prominent man.
E  The archer was between 35 and 45 years old when he died.
F  And people of that time would have been able to communicate in early Celtic tongues.