Foot of a Housefly, Musca domestica. The two claws are used to grip rough surfaces. The hairy adhesive pads, or pulvilli (beneath the claws), allow the fly to cling to smooth surfaces. Coloured SEM from Science Photo Library
LPR023 A pellet of thyme pollen near pellets of cistus, poppy, apple and rosemary pollen. Pollens are made of a multitude of microscopic, spherical grains contained in the pollen sacs of the flower anthers. Photo by Eric Tourneret
Trypanosoma, a parasitic flagellated protozoan that causes trypanosomiasis (African sleeping sickness and Chagas disease). This trypanosome is a vector-borne parasite transmitted by Tsetse Flies (Glossina).
‘Baby Kraken’, a fluorescence microscope image of a squid embryo attached to a yolk sac, by Princeton chemistry professor Celeste Nelson. This embryonic sea creature is smaller than a pea. Celeste M. Nelson / Princeton University Art of Science Competition
Cyanobacteria are photosynthetic microorganisms that contain chlorophyll. Formerly considered blue-green algae, but actually closely related to bacteria, cyanobacteria are of special importance in the balance of nature. Cyanobacteria were the earliest oxygen-producing organisms on Earth (remnants of cyanobacteria have been found in fossils dating back 2.5 billion years) and were responsible for converting Earth's non-oxygen atmosphere to oxygen
Archaea were only shown to be a separate domain—through analysis of their RNA—in 1977. Many archaea thrive under the extreme conditions of hot sulfur pools or in minerals and rock deep inside the Earth. On the floor of the ocean at thermal vents, lacking both sunlight and oxygen, they obtain energy and nutrients from chemical reactions with energetic molecules emerging from the vents and molecules on the mineral surfaces of rocks. (from the Tree of Life interactive)