Which of the following provides evidence for the hypothesis of punctuated equilibrium? A.
the discovery of many fossils of different forms corresponding to a line of ancestors for a species

B.
the discovery of a common sequence of DNA in several different species

C.
the discovery of a vestigial structure in an organism

D. the discovery of an abrupt change in DNA in a species after many generations of no change

B

Explanation:

the abdomen (less formally called the belly, stomach, tummy or midriff) constitutes the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. the region occupied by the abdomen is termed the abdominal cavity. the stomach secretes acid and enzymes that digest food. ridges of muscle tissue called rugae line the stomach. the stomach muscles contract periodically, churning food to enhance digestion. the pyloric sphincter is a muscular valve that opens to allow food to pass from the stomach to the small intestine.