Wednesday, 18 August 2010

Discovery of Sea Sponge Fossils Pushes Back Animal Life on Earth By 90 Million Years

American geologists from Princeton University have discovered tiny sea sponge fossils in rocks that are estimated to be between 640 and 650 million years old.  These ancient sea sponges only measured up to 1 cm across and lived on reefs off the coast of South Australia. These remarkable finds are the earliest fossils of of primitive early animals ever found.

It has been believed for a long time that animal life on earth emerged after the Marinoan glaciation, or 'Snowball Earth', when the whole planet was covered in ice and snow, but these new fossils push the emergence of animal life back before this cataclysmic event. This raises the question of how the reef-dwelling ancient sea sponges managed to survive the evastating period of glaciation.

Now there has been a discovery of ancient sponge fossils that are even older in the Etosha National Park in Namibia.  These tiny sponge fossils have been found in rocks that are estimated to be around 760 million years old, and scientists believe that it proves that sponges are the oldest forms of animal life on the planet.  These very early fossils are shaped like a vase and are no bigger than a speck of dust,and have been examined under electron microscope and x-rayed to find out their secrets. This exciting discovery points to the fact that animal life emerged on Earth at least 100-150 million years earlier than was previously thought, and that our very earliest ancestors were most probably sponges, from which all other animal life evolved.

Tuesday, 17 August 2010

Chipmunks in France - Invasive Species Spreading Through France

Invasive species are becoming a huge problem in many countries of the world, and although many countries now take stringent measures to prevent invasive animal or plant species taking hold, the problem continues to grow.  Northern France is currently being overun by Siberian chipmunks, a species that is not native to France.  The problem started over the border in Belgium, when a group of chipmunks were released into a park in Brussels.  The group of chipmunks began to breed and started to colonise large parts of Belgium and Northern France. They were joined by chipmunks that were bought as pets and then released by their owners, and it is estimated that there are now over 100,000 chipmunks living in the wild in France.

You might ask what the problem is, because after all aren't Siberian chipmunks cute little critters?  Well the big problem is that chipmunks are not a part of that native ecosystem, and are taking the food and out-competing native mamals and rodents.  They destroy vegetation and can be carriers of diseases such as Lyme disease and Rabies.  Experts believe that it is only a matter of time before they reach the UK, to add yet another burden on our already challenged environment.