Two Different Tall Coral Specimens. One is the multi-branched staghorn coral, genus Acropora, and the other is the more solid cauliflower coral, genus Pocillopora. 

Staghorn Size: 13 1/2 X 8 1/2 X 7 in. 

#8574 . 

Cauliflower Size: 8 X 3 X 8 1/2 in. 

#8586 . 

Corals are colonial marine invertebrates, living organisms that form compact reefs out of many individual polyps. Each polyp is a sac-like animal typically only a few millimeters in diameter and a few centimeters in height. A set of tentacles surround a central mouth opening, and the base is an exoskeleton that can combine with others via asexual reproduction. Corals obtain the majority of their energy and nutrients from photosynthetic unicellular dinoflagellates that live within their tissues. These are commonly known as zooxanthellae and give the coral their wide spectrum of color. Corals require sunlight and grow in clear, shallow water, typically at depths less than 200 feet down. The practice of bringing up, drying, and displaying coral dates back to antiquity, and the trade of coral for money or other economically viable items was documented by Pliny the Elder in the 1st Century CE. Corals are increasingly at risk of bleaching events where polyps expel the zooxanthellae in response to stress such as high water temperature or toxins. As of 2024 there are over 2100 identified separate coral species, nearly 800 of which are currently endangered and over 100 of which are at imminent risk of extinction, making their use as art less common in the modern era. Because coral does not replenish rapidly, and the microorganisms that live and feed on them are also dying out, the symbiotic biomes that form around them are also at significant risk, with implications all the way up the food chain to humans who rely on the bounty of the sea to survive.