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30th January 2018
Science
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Mystery over mass death of antelopes
Ancient rainbow dinosaur found Samhita Chaudhuri Science Writer
Alex Millard Senior Science Reporter
The mystery of why 200,000 antelopes in Kazakhstan dropped to the floor dead back in 2015 caused a major investigation. Scientists have now come to believe that the mass die-off, which wiped out the majority of the world’s population of Saiga antelopes, was caused by environmental factors. The cause of death was originally discovered to be from a bacterial infection. While this is true, environmentalists have uncovered data which suggests that uncommonly high temperatures and humidity in the region may have also be responsible. The bacterium usually lives within the antelope’s blood stream without causing a problem but the increased numbers had caused septicaemia, or blood poisoning, in the animals.
These factors were also found to occur in Asia twice previously, both preceding another mass die-off of the same species of antelope.
“Receptors are key for the coordination of environmental responses” Scientists are now investigating if the high temperatures and moisture in the air are allowing the bacteria causing the deaths to proliferate and enabling it to infect huge numbers at a time. Professor Richard Kock of the Royal Veterinary College London has been quoted as saying that it is “very, very likely to happen again”. Kock has warned that there is the possibility of a complete
extinction if this happens again before the antelope are able to stabilise their numbers. Due to this he has stated the urgent need to halt other threats to the antelope’s lives such as “poaching and the spread of diseases from livestock”. These particular antelopes are already classed as critically endangered and the International Union for the Conservation of Nature (IUCN) state that this is due to the illegal hunting for horns for use in Chinese medicine as well as loss of habitat. Scientists also believe that other wildlife species similar to the antelope, such as reindeer, could also be at risk of these mass die-offs. Steffen Zuther, co-researcher at the Frankfurt Zoological Society has told us that “the triggering of such mass mortality events shows that not much can be done to prevent them from occurring” and that this is why “it is important to maintain populations of sufficient size to survive such catastrophes.”
Habitat fragmentation threatens ‘little tiger cats’
Photo: Flickr, Sam Beebe Hannah Brown Science Writer With only around 10,000 left in the wild, the “little tiger cat”, vulnerable to extinction, has been given a new breath of hope from scientists. The güiña cat, the ‘little tiger cat’, has been studied by scientists at the University of Kent. It has recently been discovered that they can live near to humans, and can even thrive, when it was previously thought they could only live in rainforests. The güiña is about half the size of a house cat, and only lives in central and southern Chile and in a
small strip of Argentina. The biggest threat to the güiña is humans, as their habitats are being destroyed and made smaller. Farmers also kill them in fear that they will attack their chickens and other livestock. Around ten percent of farmers had said they’d killed a güiña over the last ten years. In the past 25 years however, around two-thirds of the rainforests of Chile have been destroyed for farmland, leaving the güiña cat struggling for food and shelter. Now the little tiger cats can live near humans, this does raise hope for their survival. Its biggest threat is that its
habitat is being squeezed into smaller and smaller areas. Now that they may have a new habitat, it’s hoped that the little cat can breed and thrive, hopefully growing in numbers and no longer being at a risk of extinction. The research on the güiña, published in the Journal of Applied Ecology, helps to provide scientists with a clearer picture of how all of the issues affecting the little tiger cat actually affect the survival of the species. The approach used in the studies of the güiña could help with conservation efforts for other species of small-sized carnivores in other parts of the world.
At a farm in north-eastern China’s Hebei Province, a fossil of Caihong juji (C. juji), which is Mandarin for ‘rainbow with a big crest’, was discovered. This is a fitting name for a 161 million-year-old dinosaur with a Velociraptor-like skull that has iridescent feathers on its head, wings and tail. Scientists discovered the dinosaur’s colourful nature by examining its feathers using a scanning electron microscope, which showed evidence of melanosomes. This is the part of cells that contain pigment. Despite the colour having long faded away over time, the structure of the cell still remains intact. The dinosaur, C. juji, is not
the first of its kind to sport such a feature. The Microraptor, a four-winged dinosaur also had gleaming features. However, it existed 40 million years after C. juji, which makes the newly identified dinosaur the oldest to have shimmering feathers. It would have also had asymmetrical feathers, a trait that is shared by modern birds and helps them steer while flying. While C. juji may have sported these feathers on its tail, they could have been used for early flight control, warmth and to attract mates. Not all of C. juji’s features are unusual for a dinosaur though. It had a bony head crust, but the body of an avian. This combination of new and old traits is an example of mosaic evolution, the concept of change occurring in some parts of an animal but not others.
Amur leopard endangered Photo: Flickr, William Warby
Troy Fielder Science Writer A disease that commonly effects domesticated dogs has been added to the list of threats that have critically endangered Amur leopards (Panthera pardus orientalis). So far, the list already includes illegal wildlife trade, habitat loss, fragmentation, and climate change. The recent discovery of a two-yearold Amur leopard suffering from canine distemper virus (CDV) has led to this realisation. Spotted on a roadside in Eastern Russia, the female leopard was said to show a “lack of fear towards humans” and a general detachment from her surroundings. The leopard in question was soon immobilized and transported to a local care facility, by conservationists. As well as refusing food and water, the leopard later developed “uncoordinated movements” and “severe hind limb contraction” that caregivers were unable to treat with medication. The severity of the disease led to further decline and, eventually, the leopard had to be euthanised. It is rare for cats to contract CDV, but it has previously been found that close contact with dogs can result in the disease’s occurrence in felines.
Once the disease is acquired, it can be easily spread between social cats. Luckily, Amur leopards tend to be relatively solitary animals. However, the threat remains very real for this dwindling species. As few as 60 leopards remain in the wild, according to a paper published in The Journal of Wildlife Diseases; and as the population dwindles further, the effect of external shock on the species worsens, with potentially fatal consequences.
60
57
the estimated number of wild leopards remaining the estimated number in one Russian National Park in 2015
Active conservation efforts are being carried out by organisations such as WWF, which aims to work with local governments to ensure the protection and expansion of the Amur leopard population. As apex predators in their natural habitats, conservation work like this will be crucial to the maintenance of the natural ecosystem of the environments.