In the present study, 8-d-old planulae were
used for inoculation of symbiotic algae and
were allowed to establish a stable symbiosis for
1 wk until being used in the stress experiment.
Thus the symbiotic planulae were 15 d old
when exposed to natural sunlight. The point in
coral life history at which the next generation
becomes infected by symbionts remains an open
question. Early reports suggested that infection
occurred following metamorphosis (Babcock and
Heyward 1986)