Glaciers in the harsh Arctic and Antarctic environment look lifeless, but within the ice there is a whole host of biodiversity that we just can't easily see. Microscopic ecosystems are thriving on and inside ice sheets and glaciers. Microbes are fundamental for life on Earth. For example, bacteria are the main producers of oxygen in oceans, soils and lakes. Microbes also help decompose dead matter on Earth and without it our planet would look like a landfill. Of course, even microorganisms have food chains. The pictures below are of the sun, the source of energy for some microbes, bacteria, algae and a small invertebrate known as a tardigrade found in and on glaciers. Tardigrades are also known as moss piglets or water bears: can you see why they are called that?