Attack by scavengers and bacteria, chemical decay, and destruction by erosion and other geologic agencies make the odds against preservation very high.

食腐动物和细菌的攻击、化学性腐烂，以及侵蚀和其他地质作用的破坏，导致无法保存的可能性非常大。

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Ants store food, repel attackers and use chemical signals to contact one another in case of attack.

蚂蚁储存食物，击退攻击者，并使用化学信号联系彼此以防被攻击。

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This apparently walks back from a Bush-era declaration that underscored the possibility that the United States might use nuclear weapons if it suffered a chemical or biological attack.

这显然是走回布什时代的宣言，强调了美国可能会使用核武器如果它受到了化学或生物武器的袭击的可能性。

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Asked what they though terrorists might do next, 37 percent said attack with chemical or biological weapons, while 18 percent expect a bombing or an attack on a public place or infrastructure.

CNN: Survey: Shock from terror attacks receding

With or without chemical arms control agreements, the United States will continue to confront adversaries equipped with CW. If it wishes to minimize the chances that it will be the victim of chemical attacks, the U.S. must retain a modest, but reliable, capability to respond to any such attack with chemical weapons.

CENTERFORSECURITYPOLICY: Center for Security Policy | Bush��s Myopia On Chemical Weapons Keeps Him From Seeing Handwriting On Arms Control Wall

The blast-proof bus has armour-plated glass and was thought to offer protection from chemical attack.

BBC: Margaret Thatcher 'battle bus' sells in Towcester auction