Have you seen corals in real life? Which ones? Where?
Corals are made of colonies of polyps and have three ways to increase their numbers:
🔸 Asexual reproduction, where “parental” polyps bud to boost numbers within a colony
🔸 Fragmentation, when a section of coral falls away to establish a new colony
🔸 Sexual reproduction by spawning or by brooding
Sexual reproduction by brooding (as illustrated) can be important for the coral to increase genetic variation, but another major advantage is that it forms new colonies far away from the parental one.
The corals coordinate this process by the phases of the moon with sperm released (1) during the new moon and the larvae released (4) at the full moon, after a period of brooding in the polyps (2-4).
The larvae are then dispersed on the ocean currents until they find a home to begin developing a new colony.
Thank you to 🇨🇴🇦🇺 Lucia Garces, fellow demonstrator and scientific illustrator at St. George’s University. She’s also a graphic designer and nature lover.
Lucia made this image for Stephen Nimrod, assistant professor in the Department of Biology, Ecology & Conservation.