Annie Oakley was born in 1860 in Darke County, Ohio. Her family was very poor. She decided to help family even when she was young, so she learned to use a gun, and began hunting animals for food. She could shoot them without losing the important parts of the meat.

    Soon her shooting ability became well known. When she was sixteen, she was invited to a competition with a famous marksman(神枪手) , Frank Butler. Annie surprised everyone by winning the competition. Later that year she and Frank married.

    In 1882 Annie Oakley and Frank Butler started putting on shows together. Frank Butler was the star of the show and she was his assistant. The famous native American leader, Sitting Bull, thought so highly of her shooting ability that he called her "Little Sure Shot". Later Annie Oakley became the star of the show and Frank Butler was her assistant. Posters （海报）for the show called her the "Champion Markswoman".

    During World War I, Annie Oakley wanted to train a group of women volunteers for the army, but the United States did not accept it. She gave American soldiers shooting lessons, and traveled across the country visiting many training camps. She gave shooting performance and raised money to support the American soldiers.

    Annie Oakley died on November 3, 1926. Eighteen days later, Frank Butler died too.

在过去的2亿年中，自然界大约每二十七年就有一种植物从地球上消失，每个世纪有90多种脊椎动物灭绝。而现在物种灭绝的速度是自然灭绝速度的1000倍，你认为造成这种结果的原因是（　　）