Hour Glass Dolphin
As weird as the name of this species of dolphins comes across, the complex anatomical makeup of these dolphins gives them their rather funny name. With markings on its side that greatly resemble the two ends of a sand glass hour, this popular dolphin is found mainly in the southern hemisphere.
 

Unlike most of other species this species is considered to be relatively untouched by human perils and hence does not face any substantial threat such as extinction. They are unique in the method in which they surface the sea, during times which they resemble penguins and they also gain prominence due to their ability to spin on the waves.