Listen to the following recording, and fill the gaps in the summary below.
Fill the gaps with a maximum of TWO words and/or a number.
For centuries people have been able to improve their lifespans through _____ changes. However, a recent study has found that the limits of _____ may have already been reached. It is believed that the maximum lifespan may have peaked around the year _____. Researchers concluded that humans can typically live for a maximum of _____ years, and that the absolute upper age limit is _____. They recommend that we make efforts to improve the _____ of life, rather than to extend life expectancy.