Species return sparks fresh interest
SMALL PRINTS:NEW species are not just discovered in exotic places – even temperate climates such as Ireland still yield discoveries of new plants and animals. Scientists at the Natural History Museum in Paris have recently named a new species of chimaera, an ancient and bizarre group of fishes distantly related to sharks, from the west coast of Ireland.
The new species, the Opal Ghostshark or Opal Chimaera (Chimaera opalescens), was described in the Journal of Fish Biology after its discovery in a French fish market. French trawlers fishing in Irish waters recovered the strange creature.
Chimaeras, also called ratfish, rabbitfish and ghostsharks, are perhaps the oldest and most enigmatic group of fishes alive today.
The huge eyes and nibbling snout look like a rabbit’s, inspiring the label “rabbitfish”. The tail is long and thin, like a rodent’s – hence the other common name “ratfish”. Their closest living relatives are sharks, but their evolutionary lineage branched off from sharks nearly 400 million years ago, and they have remained an isolated group ever since. Chimaeras are common in the fossil record, and they survived through the age of dinosaurs mostly unchanged.
Prior to this discovery, only one species of Chimaera was reported from the north-eastern Atlantic Ocean, and just 10 other species of Chimaera are known to date.
Dr Declan Quigley, who works with the Sea-Fisheries Protection Authority, is an expert on rare fish and explains that this is the first time in more than 100 years that a fish new to science has been discovered in Irish waters.
“I’m sure that there are other things out there new to science but nobody is looking,” says Quigley. The gap in our knowledge of marine animals is where there is no fishery. So species living at depths of 200 to 1,000 metres are the big knowledge gap, according to Quigley.
– Eugenie Regan
Solar storm's path to Earth revealed
THANKS to a good view and some fancy software, scientists have been able to track for the first time the path of a solar storm as it moves out from the Sun along the 149 million kilometres or so to Earth.
Researchers looked at a hot cloud of high-energy gas called a coronal mass ejection (CME), which burst from the Sun back in December 2008. Such CMEs take about two to three days to reach Earth and can affect our planet’s magnetic field. Using data from the twin space probes Stereo, the study could pick out light reflected by the CME as it travelled all the way to Earth, as shown in a video released by Nasa. Tracking that path was an accomplishment, according to Dr Peter Gallagher, a solar physicist at Trinity College, Dublin.
He was not involved in this study but his group has perviously tracked the three-dimensional path of the same CME for about half of its journey to Earth. “As a CME moves away from the Sun it gets progressively more dim, and once it gets halfway to the Earth they are almost impossible to see,” he says. “But new image-processing software lets you highlight the CME and you can see it moving the whole way to Earth.”
The new study offers a step towards working out how CMEs interact with Earth, according to Gallagher, who was struck by how small our home planet looked in relation to the CME washing over it. It’s a sentiment echoed on Nasa’s website by study author Craig DeForest of the Southwest Research Institute in Boulder, Colorado.
“The movie sent chills down my spine, he says. It shows a CME swelling into an enormous wall of plasma and then washing over the tiny blue speck of Earth where we live. I felt very small.
– Claire O’Connell