The crown-of-thorns starfish (Acanthaster planci) is named...

The crown-of-thorns starfish (Acanthaster planci) is named for the brightly colored spikes that coat the legs. A. planci can grow up to 16 inches across and can have between 12 and 19 legs. The spikes coating A. planci hold poison that can cause temporary paralysis at the sting site and can also cause nausea in humans. A. planci can also regrow arms. At the end of each of the arms is an eyespot that can detect light and darkness, but can not detect color and shape (Fisher 2011). A. planci preys on coral and a single starfish can eat up to 10 sq. meters of coral each year. A. planci kills approximately 161 sq. cm. per day in the winter and 357-478 sq. cm. per day in the summer. In order to eat the coral, A. planci pulls its stomach out†¦show more content†¦The small shrimp, Hymenocera picta, is a general predator of all starfish and has been found to prey on A. planci at some locations. Pherecardia striata can only attack damaged A. planci and cause its death. Therefore, P. striata is regarded as a scavenger rather than as a predator. A. planci attracts many other scavengers who are able to tolerate A. planci’s horrible taste for the chance at a food source (Fisher 2011). There is increasing evidence in numerous scientific studies that show that widespread marine species can be highly structured genetically and may speciate very quickly. Genetic differentiation of populations in the Indian and the Pacific Oceans has been reported for coco nut crabs (Lavery et al. 1996), the starfish Linckia laevigata (Williams and Benzie 1997), butterfly fish (McMillan and Palumbi 1995), damsel fish (Lacson and Clark 1995), and the mangrove Avicennia marina (Duke et al. 1998). Despite the evidence of high gene flow within the Indian and the Pacific Oceans, this still holds true. This suggests that there is high dispersal over large areas. However, there is limited dispersal between zones. Contrary to the aforementioned data about other species, there is little genetic divergence of sibling species of sea urchins (Echinometra spp.) in the Pacific Ocean. This suggests recent speciation, but it also suggests rapid dispersal after speciation (Palumbi 1994). These discrepancies of results show that there is a need to