A beautiful new image has been just been captured of the recently named Manatee Nebula. The photo, taken by the Very Large Array radio telescope network in New Mexico, closely resembles the way manatees look when in one of their favorite positions, floating on their backs with their fins across their bellies.
The nebula was only very recently named, before that it was known as W50. The name was given with the intention of driving more attention to the highly endangered species. The primary threat that manatees face is from being injured/killed by motorboats, which happens very commonly in the areas they live in throughout the greater Gulf of Mexico.
“Manatees are endangered, in part because boat propellers often cut deep gashes into the herbivores’ sides, injuring or killing many manatees every year. The nebula, too, bears streaky scars carved out by particles in the two protruding jets emitting from the black hole at its core.”
It’s a very unfortunate situation for them, as they are very interesting animals. I’ve come across them in the wild before, and they are very strange, large, and surprisingly graceful animals. Very curious also. But like many animals native to Florida, especially large mammals, they have seen their numbers plummet in the past 100 or so years as development in Florida has accelerated. The nebula named after them will very likely be in the world for considerably longer than they will.
Th Manatee Nebula was actually only created rather recently, about 20,000 years ago, from a large supernova explosion. The leftovers of that explosion are the nebula. Before the star that formed it died, it “puffed out its outer gaseous layers, which now swirl in green-and-blue clouds around the dead hulk of the star, which has collapsed into a black hole.”
In related news, the oldest-ever fossils of a sea-cow have recently been discovered in Tunisia. The fossils represent the earliest known ancestor of the manatee, and related extant species such as the dugong. The discovery supports the theory of an African origin for these animals.
Previously, there have been fossils of sea cow ancestors found in Jamaica, but the Tunisian fossils predate those. And they represent a more transitionary form than the Jamaican fossils do.
These fossils show that sea cows emerged as a species roughly at the same time as many other modern mammals did. But “unlike whales and dolphins, the evolutionary origins of the sea cow family have been obscure.”
“They share an ancestor with elephants, and it is thought that their oldest relatives were terrestrial animals that gradually adapted to an aquatic life. The last common ancestor of the two species may have lived in freshwater swamps well before the time that the new species described in this study lived.”
“Though this specimen may not have been the common link between modern day sea cows and elephants, the authors’ analyses suggest that this new species lived in fresh water, not sea waters.”
The discovery was published January 16th in the open access journal PLOS ONE.
Image Credits: NRAO/AUI/NSF, K. Golap, M. Goss; NASA’s Wide Field Survey Explorer (WISE); Manatees and Pezosiren via Wikimedia Commons
