21.   Dams can have a devastating effect on some aquatic species, scientists have learned.

22.   During the past few decades, scientists have learned that matter is made up of three distinct flavors or types.

23.   Even if he died from the experiment, Getty said he would be happy if scientists learned something from it.

24.   Georgia agricultural scientists have learned that these chemical signals are so specific, that they can convey the type and species of the attacking insect.

25.   If scientists can learn more about how the rice grows and reproduces, Oxley says, we can better manage it in the wild.

26.   If scientists learn to read these signals, they may deliver a message about the early stages of planet formation.

27.   If scientists learned anything last fall, it was how little they knew about the germ and the disease it causes.

28.   If scientists had learned how that acid production was shut off, it might have helped them develop a new ulcer treatment for humans.

29.   In the past year, scientists have learned that nicotine behaves very much like cocaine and affects the same area of the brain as alcohol, cocaine and heroin.

30.   In some cases scientists are learning whole sequences of maneuvers meant to escape predators.