91.   If evolution is still unfolding, and most scientists believe it is, just how complex an organism could the evolutionary process create, before hitting some fundamental limit?

92.   If I understand it correctly, scientists believe these bacteria were getting along swimmingly until the sea around them began drying up sometime during the late Paleozoic period.

93.   In animal studies of chemicals that cause birth defects, timing and dose are critical and scientists believe the same is true for humans.

94.   In atherosclerosis, many scientists believe that oxidized fat droplets, circulating in the bloodstream, irritate the artery wall.

95.   In August Congress lifted a ban on such research, which scientists believe could lead to cures for many diseases.

96.   In particular, amphetamines act on a brain chemical called dopamine, which scientists believe is responsible for the euphoria the drugs produce and also their potential for abuse.

97.   In fact, Pathfinder scientists believe the flood Malin described was most likely only one of many.

98.   In groups of three, scientists believe, they combine to form the protons and neurons that combine in the atomic nucleus.

99.   In the darkness of an underground cave lined with prehistoric paintings, French scientists believe they have discovered the oldest footprints of humans in Europe.

100.   In this fascinating article, Jo Ann C. Gutin reports on how scientists believe great artists are more likely to suffer from manic depression than the rest of us.