This beautiful creature referred to as “dandelion” was discovered by geologists during a 1977 expedition. Scientists now know that it is a siphonophore, a relative of the Portuguese man-of-war. Animals living near hydrothermal vents have to survive under harsh conditions like high pressure, steep temperature gradients, and high concentrations of toxic chemicals. Despite these seemingly inhospitable conditions, many animals do more than simply survive. They thrive in an underwater environment more than a mile down!