Seahorses are captured by the millions in China due to being used in Chinese medicine. They're also used for commercial use such as pendants and key chains. They also fall victims to fishing nets. Because of this they're facing extinction :( Want to help? google petitions to save them and support Ocean conservation organizations, like Oceana :)
Blue Ring Octopus: This golf ball size Octopus can inject a deadly neurotoxin and stop your heart in minutes. There is not know antidote and survival requires constant heart compression and assisted breathing until the toxin is out of the body...about 24 hours. Super pretty though.