The photo has 2 identical dolphins in it. It was used in a
case study on stress level at St. Mary's Hospital.

Look at both dolphins jumping out of the water. The dolphins are
identical. A closely monitored, scientific study of a group revealed
that in spite of the fact that the dolphins are identical, a person
under stress would find differences in the two dolphins. If there are
many differences found between both dolphins, it means that the person
is experiencing a great amount of stress. Look at the photograph and if
you find more than one or two differences you may want to take a
vacation.