 ESO 1 Science  DownloadPreviousNextClose 1. The Earth in the Universe Sputnik news reel. Watch this news reel from Universal Studios on the launch of Sputnik in 1957, the first man-made satellite ever put into orbit.  Apollo 11 mission highlights. Watch that small step for a man, but giant leap for Mankind.  Audio file from the Apollo 13 mission. Listen to one of the most frightening moments ever lived in space.   Really big stars. Want to see something really big? Well watch this. Check out how our own moon compares to the largest star we currently know about, VY Canis Majoris.  Planets and stars to Scale. Watch from the smallest planet in the Solar System to the biggest known star.  The known Universe. From the Himalayas through our atmosphere and the inky black of space to the afterglow of the Big Bang.            Earth rise from the Moon. Recorded in April 2008 by the Kaguya (Selene) spaceprobe from the Japan Aerospace Exploration Agency. Reasons for seasons. Discover why winter and summer have nothing to do with the proximity of the Earth to the Sun in this Uncommon Knowledge podcast.  Total lunar eclipse. Total lunar eclipse of February 20, 2008, in slow motion. 2. Matter Eureka! - Volume and density. Learn how a "car crusher machine" can help your father to reduce both the volume and the density of his car.  Meet the elements. Sing and learn the properties of some chief elements.  Mixtures and compounds. Learn the difference!  Eureka! - Atoms. Learn how matter is made up of molecules built with very different types of smaller particles: the atoms.  Eureka! - Electrons. Learn that atoms are made up of even tinier particles and a lot of empty space.  Eureka! - Molecules in solids. Maybe you thought they weren't moving… but see their dance!   Eureka! - Evaporation and condensation. Learn how are the molecules in a gas, and what can make liquids turn into gases… and viceversa.  Eureka! - Expansion and contraction. And now learn that that was because the heat affects the movement of the molecules of the objects. 3. The Atmosphere and the Weather Jake's attic - Can implosion. Watch a soda can being crushed by air pressure.  Jake's attic - Balloon in a bottle. See how atmospheric pressure pushes a ballon into a bottle. 4. The Water and the Hydrosphere Ocean currents. Learn which are the major ocean currents and how they circulate. 7. Prokaryotes, Protozoa, Algae and Fungi Bacteria. You might not see them, but they're there.  Bacterian growth. Watch a colony of bacteria multiplying. Iron will to live for Antarctic microbes. A study in the journal Science shows that microbes have long survived under glaciers in Antarctica making do with nothing but sulfates and iron from the bedrock.  Microscopic world I. Beautiful movie showing algae, protozoa and small invertebrates dancing in a lake.  Small world. Much the same thing as the previous one. Protozoa and lots of algae.  Amoeba gobbles algae cells. Well, they do have to eat also, don't they?  Cilia and flagella. More on protozoan movement. With sound.  Fungi. Fungi in all their beautiness.  Mushroom madness. Extracted from the BBC/NHK documentary Planet Earth.  Blue oyster mushrooms growing. Beautiful time-lapse movie showing the growth of the many mushrooms produced by a single fungus.  Mould on rotting apple. Another time-lapse movie showing the not-so-riveting growth of these inferior fungi. Fungi: the good, the bad and the edible. Though fungi are essential in the production of bread, beer and some cheeses, it can also be a threat to human life in the form of deadly disease and infection. Fungi experts discuss the diverse and complex nature of this underappreciated kingdom of organisms. 8. The Plant Kingdom Adaptations of plants. Learn how plants have evolved to perform efficiently the vital functions.  Adaptations of leaves. Watch how the plants' leaves can be strongly modified to help improve a plant's adaptation to an specific environment or lifestyle. 9. The Animal Kingdom Amazing octopus camouflage. It is not a ghost, although it certainly looks like it.  Life of a monarch butterfly. From the caterpillar to the imago.  Monarch butterfly caterpillar pupating. Watch the monarch butterfly caterpillar forming the chrysalis.  Painted lady butterflies. Later life stages of several painted lady butterflies: caterpillar, pupa and imago.  Caterpillars. See how amazingly these vulnerable creatures manage to survive.  Ants. Watch the most stunning ants' nest that you could ever think of.  Sea turtles and their hatchlings. Watch how sea turtles lay their eggs in the sand and how their hatchlings must immediately make it to the water.   Smarter city birds. Biologists are comparing country bumpkins and city slickers... among birds!  Partnerships. Watch how patience and interspecific tolerance bring about common benefits for mammals and birds. Primate not so innocent. A recent study shows that chimps can make long-term plans, because one was found saving up stones to throw at people.  ESO 2 Science DownloadPreviousNextClose 1. Forces and Movements Eureka! - Inertia. Objects like to remain the way the are: static or moving. That laziness is called inertia. Learn about it.   Eureka! - Forces and speed. Learn how the force needed to move an object depends on the mass of the object and how much you want to increase its speed.  Eureka! - Acceleration (I). That was not quite true. In fact, the force depends on the mass of the object to move and how fast you want to increase its speed. Watch it.  Eureka! - Acceleration (II). Let a locomotive driver show to you that acceleration is how much the speed of an object changes every second.   Eureka! - Weight. Learn that you can easily lose weight without diets - you only have to go to the Moon!  Theory of gravity tested on the Moon. Drop a hammer and a feather on the Moon, and which one will hit the surface first?  Eureka! - Buoyancy. Learn that the buoyancy of an object is the result of a balance between two forces: the weight of the object and the weight of the displaced fluid. 2. Energy Eureka! - Work. Energy is the ability to do work, so it' time to learn what work is and how it relates to force.   Eureka! - Potential energy. Let David and Goliath explain to you what potential energy is and how can it be transformed into kinetic energy.  Wind turbines make bat lungs explode. Researchers at the University of Calgary have found out why bats have been dying near wind turbines. Old energy source wood be new alternative. A recent scientific paper praises the energetic potential of an old resource: wood. A truly green source of energy: algae. Ira Flatow and guests discuss the future of algae-based energy, including plans for a new algae-fueled power plant in Venice, Italy. Biologist Jerry Brand explains why biotech companies are snapping up samples from his extensive algae collection at the University of Texas at Austin. 3. Heat and Temperature Eureka! - Temperature vs. heat. Learn the difference between "degree of hotness" and "quantity of hotness".  Eureka! - Measuring temperature. You need something better than just "too cold" or "too hot", isn't it? Learn how Anders Celsius came up with the solution…  Eureka! - Heat as energy. Learn that heat is just another kind of energy, and can be transmitted.  Temperature. Can an individual atom be hot or cold? Can it even have a temperature? Find out now! Temperature vs. heat. Find out the difference between heat and temperature in this Uncommon Knowledge podcast.  Eureka! - Conduction. Learn that heat can be transmitted by the vibration of an atom (or molecules) to its neighbours… which is what makes metals to be so good heat conductors.  Eureka! - Convection. Learn that heat can also be conveyed by fluids thanks to the principle of buoyancy.  4. Light Eureka! - Radiation spectrum. Learn what makes tomatoes be red and black colour warmer than white. 5. Sound Sound waves on fire. Pump some flammable gas into one side of a tube, and attach a speaker to the other side, and watch what happens to the columns of flames that issue from small holes along the top. 6. Chemical Changes Chemical party. Watch almost real chemical elements interacting live. 9. Interaction and Coordination in Living BeingsButterfly larvae trick ants with scent and sound. Ecologists report in Science how a species of butterfly tricks red ants into caring for them. The larvae chemically "smell" like ants, and can imitate noises that the ant queens make. Ecologist Jeremy Thomas describes the intertwined natural history of these two species. Streamed from NPR Science Friday Podcast. 10. Reproduction in Living Beings Methods of pollination. Learn how plants manage to be pollinated and to avoid self-pollination.  Wild orchid wasp mimic. This incredible plant dupes wasps into thinking they're mating, while loading them with pollen.  Fruit development. A fruit consists of seeds enclosed in a mature ovary of a flowering plant. The wall of the ovary in an apple hardened and the supporting stem become fleshy and grows up and around the ovary.  Corn growing. Watch seeds of corn developing roots and leaves.  Asexual reproduction in plants. Learn about the several means plants have to reproduce asexually. 11. The Ecosphere and the Ecosystems Trash and recycle. A funny and silly explanation of recycling by Steve Trash.  Electronic waste recycling in India. Documentary by Greenpeace showing the harm that computer recycling in India is inflicting on workers' health. Underlines why recycling needs to be carefully regulated.  ESO 3 Biology and Geology DownloadPreviousNextClose 1. Organization of Living Matter Carbohydrates. Great video that makes use of the Periodic Table to explain how a glucose molecule, the primary component of many bigger carbohydrates, is chemically constructed.  Lipids. See how a triglicerid, the most typical lipid molecule, is built from three fatty acids and one molecule of glycerine.  Proteins. Learn how a protein molecule is built up until it is fully functional.  DNA Structure. Learn how a molecule of DNA is structured.   DNA wrapping and replication. The first part shows the DNA coiling four consecutive times to make up the chromosomes. The second shows the process of DNA duplication before cell division.  Chromosomes. How many chromosomes do humans have? How about a dog? Check out this video to find out more about chromosomes.   2. Nutrition in Humans 3D human anatomy. 3D visualization from actual CAT scan and MRI data of living subjects.  Digestive system. Short introductory video on the function of the digestive system.  Digestion. Watch the digestion process.  Respiratory system (I). Respiration 3D Medical Animation, with very detailed information.  Respiratory system (II). The mechanism of breathing and the anatomy of the organs that carry out this activity, brought vividly to life through revealing animation and x-ray motion pictures. Produced by the Phoenix Learning Group  Respiratory system (III). Learn about how the blood oxygenates and deoxygenates.  Gas exchange. Learn how gas exchange is performed in the alveoli.   Circulatory system (I). Learn about the journey of the blood throughout the body.  Circulatory system (II). Watch the path of a red blood cell around the body.  Rotating heart. Watch the heart's valves working in a translucent rotating heart.  The work of the heart (I). Learn about the heart's pumping action, its valves, chambers, movements and function.  The work of the heart (II). Learn how the pumping action of the heart is triggered.  Urinary system. Overall view on the roles of the different organs in the urinary system.  The function of the nephron. Learn how urine is progressively produced in the different parts of every nephron. 3. Interaction in Humans Neurones. Introductory video to the role of neurones in the human body.  Nervous system (I). Short introductory video on the function of the nervous system.  Nervous system (II). Explore the nervous system through a series of animated sequences that trace the structure of neurons and illuminate biochemical impulses. Produced by The Phoenix Learning Group  Backbone anatomy. Cervical spine and intervertebral disc anatomy. Caffeine. Learn how caffeine tricks your brain into thinking it is not tired when it really is.  Skin, nails and hair. Short introductory video on the function of the skin, the nails and the hair.  Seeing. Short introductory video on the process of seeing.  Hearing and balance (I). Short introductory video on the senses of hearing and equilibrium.  Hearing and balance (II). Hearing and equilibrium explained through drawings.  Smelling and tasting. Short introductory video on the senses of smelling and tasting.  Endocrine system. Short introductory video on the function of the endocrine system and the hormones.  Motor apparatus. Short introductory video on the function and components of the motor apparatus. 4. Reproduction in Humans Female reproductive system. The female reproductive system with some detail.  Human ovulation. Human ovulation captured on film for the first time.  The Menstrual cycle. Learn how hormones control the menstrual cycle. Produced by How the Body Works  Reproduction. Short introductory video to the reproductive process in humans.  Conception. See how conception takes place.  Cell to embryo. Watch the amazing transformation of a fertilized egg into an 8-week embryo in this video made from magnetic resonance images.  From conception to the fifth month. Detailed video on the events of the first months of fetal development.  From weeks 6 to 12. Animation showing the changes between the sixth and the twelfth week of gestation.  Development of the fetus (I). Stage by stage description of the changes during human fetal development.  Development of the fetus (II). Stage by stage depiction of the human fetal development.  Childbirth (I). Animation of a normal vaginal birth.  Childbirth (II). Detailed explanation on how a typical childbirth takes place. Pill may change attraction. In a recent study researchers note that the birth control pill may change a woman's choice in whom she finds attractive.  Childbirth the Monty Python's way. Fragment from the Monty Python's film "The meaning of Life"… with the very expensive machine that goes "ping". You can read the transcript at http://www.mwscomp.com/movies/mol/m-03-i.htm. 5. Health and Disease Infection fighters. Short introductory video on the immune system and the skin as infection fighters of our body.  White blood cell chasing a bacterium. Watch a neutrophil white blood cell going after a bacterium in the blood. Less fungus among us warm-blooded. A recent study finds that one major advantage of being warm-blooded is that the great majority of fungi cannot infect us. Fruit juices block some drugs. A recent discovery points out that drinking some fruit juices might have some unexpected side-effects. 7. Rocks  ESO 4 Biology and Geology DownloadPreviousNextClose 1. Cellular Functions The cell membrane. Learn the structure, behaviour and biological meaning of the cell's plasma membrane.  Diffusion. Learn how the molecules of fluids move freely, and which force drives their motion.  Osmosis. Learn how the process of diffusion can equalize the concentrations of two solutions to either side of a semipermeable membrane.  Passive transport. Learn how some proteins of the plasma membrane can allow a free movement of molecules in and out the cell.  Active transport (I). Learn how some proteins of the plasma membrane can pump certain substances through the membrane against the concentration gradient with some contribution of energy.  Active transport (II). A more detailed view of the process of active transport through the Na/K pump example.  Endocytosis and exocytosis (I). Learn how plasma membrane sacs can help to transport materials in bulk in and out the cell.  Endocytosis and exocytosis (II). A more detailed view on the role of the endoplasmic reticulum, the Golgi apparatus and the cell's membrane lipid bilayer in the processes of exocytosis and endocytosis.  Mitosis (I). The mitotic process explained through an animated movie. [Some key words: thread, coil, unwind, spindle, fiber].  Mitosis (II). Another animated movie on mitosis, this time silent.  Mitosis (III). The central stages of mitosis in a microscopic movie.  Meiosis. The meiotic process explained through an animated movie. 2. Heredity and Transmission Mendel's gene theory explained. A quite aged but still great and clear explanation of Mendel's works.  Heredity. Basic Mendelian Genetics explained in a simple way.   Genetics 101 Part 2: What are SNPs? On molecular-level mutations and inherited variation.  Genetics 101 Part 3: Where do your genes come from? On chromosomes and gender inheritance.  Genetics 101 Part 4: What is phenotype? On the phenotype and its genetic and environmental influences.  From genes to proteins. Watch the biochemical process by which a gene's expression yields a protein.  Code for Life (I). Beginning more than three and a half billion years ago, a tiny, primitive molecule encoded instructions, deep within itself, that it passed to its children, who passed it to their children and so on—all the way down through time to all living things today. Watch the story of DNA.       Genetic engineering (I). Genetic engineering put simple.  Genetic engineering (II). Comprehensive video on the basic process of genetic engineering: creating recombinant DNA from different species.  Gene therapy. See how a virus can be recombined with human DNA to save the life of a person.  DNA matching. DNA matching is used as a tool in a variety of applications, from paternity determinations to criminal forensics. Learn how it is done.  DNA fingerprinting. A closer look to the DNA matching technique.  High speed gene sequencing. Commercial video from a firm that has developed a high speed DNA sequencer. Produced by Helicos Bioscience Corp.  Nuclear transfer (I). Animation showing how an egg-cell is enucleated and then provided with a diploid nucleus taken from a somatic cell.  Nuclear transfer (II). Watch how the nuclear transfer process is actually performed. 3. The Evolution of Living Matter On the origin of species: first paragraphs. Listen to the starter paragraphs of the most influential book in the History of Science, Darwin's "On the Origin of Species by Means of Natural Selection, or The Preservation of Favoured Races in the Struggle for Life".  Evolution primer: who was Charles Darwin? Discover how Darwin's curiosity, his passion for natural history, his voyage on the Beagle, and his use of the scientific process led to the publication of his groundbreaking book. Naked evolution. It's 150 years since Darwin's theory of Evolution was presented to the Linnean Society, and so we've Naturally Selected the Science of Evolution! We find out why scientists have revisited a textbook example of natural selection in action, find out why horny sheep are gambling on good weather and how bacteria in the lab can evolve into a new species! We find out why tragedy almost kept Darwin's ideas from ever being seen, by looking at the archives of his own letters. Plus, why crocodiles chat from inside their eggs, a new way to send messages underwater and why Martian soil would be good for growing cabbages! And in kitchen science we find out which surface is best for keeping ice cool. Charles Darwin in Australia. Professor Frank Nicholas has written a book called Charles Darwin in Australia, in which he writes about Darwin's experiences while in this country during the Beagle's expedition. Lamarck's evolution. Before Charles Darwin, Jean-Baptiste de Lamarck created the first theory of evolution in 1809. However, his theory was discredited by most in the scientific community once Charles Darwin published his theory of evolution, 50 years later. Ross Honeywill tells us this fascinating story.   Facts of evolution (II). Examining transitional fossils, progression in fossil sequences, vestigial organs, geographical trails, homologous organs and "bad-designed" organs.  Facts of evolution (III). Examining extinctions, the fossil record, the concept of species, hybrids and speciation.  Facts of evolution (IV). Examining evolution rates, embrionary development and common biochemistry.  Facts of evolution (V). Examining genome and protein comparisons between species and transposones.  Facts of evolution (VI). Examining pseudogenes and endogenous retroviruses.  Mechanisms of evolution (I). Examining how genetic variety arises in biological populations.  Mechanisms of evolution (II). Examining how natural selection acting upon biological diversity drives evolution.  Natural selection made easy. Well explained overview of the process of natural selection and how old Darwin's theory itself has had to adapt to survive under the new discoveries of Genetics.  The Theory of Evolution made easy. Learn some evidence that makes evolution an accepted fact among biologists all over the world.  Evolution primer: how do we know evolution happens? Learn about evolution through the fossil remains of whales' land-dwelling ancestors  Evolution primer: how does evolution really work? Travel to Ecuador to see how the process of natural selection operates in populations of rainforest hummingbirds.  Evolution primer: why does Evolution matter now? Learn how tuberculosis is transmitted and why the evolution of multi-drug resistant strains of TB in Russia affects us all.  Gradual evolution. The odds that such a complex organ as the human eye could have showed up all at once, and just randomly, are extremely low, creationists say. But the chances for it to appear gradually, step by step, are really high. And this fact can't be better explained than the way this video does.  Gradual evolution of a complex organ: the eye. But can something like the human eye, that seems to only have any sense once it was fully developed, really appear by gradual evolution? Richard Dawkins explains how.  Evolution primer: isn't Evolution just a theory? Learn the difference between the scientific and everyday use of key vocabulary words.  Evolution primer: why is Evolution controversial anyway? Consider different points of view, as scientists, religious leaders, and college students share their opinions about evolution, science, and religious faith.  The scientific method made easy. Learn the rules of the scientific method of knowledge, starting by that of "conclusions must be based on empirical evidence".  Creation science made easy. Learn why creation science is not science, and why the creation theory is not even a theory. 4. Natural History of the Earth The story of the Earth made easy. Learn how a geological picture can be related to geological events that happened in the past, and how all this can help us to ellucidate the story of our planet.  The age of our world made easy. Learn the basics on the dating techniques used in Paleontology.  Carbon dating. Find out how carbon is used to determine how long ago an organism had died. Fossilised fence posts. How much time does wood take to fossilise?  Paleo Earth. Watch the evolution of the Eath's continents thoughout the Phanerozoic eon.  The origin of Life made easy. Learn how could living matter come from non-living sludge.  Life to Eve (I). From the primordial organic soup to the first vertebrates.  Life to Eve (II). From the first amphibians to the extinction of the dinosaurs.  Life to Eve (III). From the extinction of the dinosaurs to the first modern humans.  Highway of Life (I). Great animation showing how Life on Earth evolved, diversified and increased in complexity from the primordial organic soup to the first fish.  Highway of Life (II). Great animation showing how Life on Earth evolved, diversified and increased in complexity from the first fish up to humans.  Evolution of vertebrates. Nice animation showing the evolutionary lineage that lead from the fish to hominids.  Dinosaur bird bones. Some hollow bones are providing solid new evidence of how birds evolved from dinosaurs. Did bugs do in the Dinos? Did a massive asteroid kill off the dinosaurs? Maybe not. Entomologist George Poinar thinks something much smaller might have done the job.  Evolution of human ancestry 101. Wonderful animated short movie about the history of human lineage.  Evolution primer: did humans evolve? Examine the fossil and molecular evidence that supports the evolution of humans from earlier primate ancestors.  Human evolution made easy. Learn how scientists came up with the idea of human evolution from the apes, and which are the fundamental patterns in human evolution.  Human ancestry made easy. This video traces our migration out of Africa and explains, through DNA evidence, how humans colonized the world. Anthropologist Donald Johanson On "Lucy's Legacy". In 1974, at age 31, Donald Johanson discovered the fossil he dubbed "Lucy", a previously unknown species of ancient hominid. Johanson talks about what the discovery meant for the human family tree and discusses his new book Lucy's Legacy: The Quest for Human Origins. 5. Plant Physiology Zoom into a leaf. Watch the surface and the inside of a leaf progressively magnified by an electron microscope.  Photosynthesis. Learn how photosynthesis is performed inside the chloroplasts.  Respiration. Learn if and when a plant respires, absorbing CO2 and producing O2.  Plant fertilization. Learn how male and female gametes fuse in plants and what happens afterwards.  Double fertilization in flowering plants. Detailed view of the process of fertilization in plants.  Reproduction of the pine tree. Learn the specificities of the reproduction process in the gymnosperms.  Plant hormones and growth. Learn how plant hormones control their growth towards the light. Leaves maintain a constant temperature. A 60-second Science podcast. 6. Dynamics of Ecosystems Global Warming. Global Warming is a hot topic. This video looks at the evidence and focuses on these two questions: "is the Earth getting warmer?" and "what are the effects of Carbon Dioxide in the atmosphere?"  The truth about climate change. A simple and effective way to see how human activity relates to global warming.  Teens, frogs and climate change. With frogs and other amphibians already dying in large numbers, a group of teenagers is joining other amateur scientists to gather information on the problem.  Early birds and springtime. A growing body of evidence shows that birds are nesting earlier due to global warming, with potentially harmful consequences.  Coal combustion and acid rain. Watch how sulphur-rich coal is a major source of acid rain and what can be done to mitigate its damage.  Analysing acid rain. Visit this research station in the Black Forest, Germany, to watch rainwater being tested for acidity.  The disappearing male. Documentary about one of the most important, and least publicized, issues facing the human species: the toxic threat to the male reproductive system. The last few decades have seen steady and dramatic increases in the incidence of boys and young men suffering from genital deformities, low sperm count, sperm abnormalities and testicular cancer. At the same time, boys are now far more at risk of suffering from ADHD, autism, Tourette's syndrome, cerebral palsy, and dyslexia. The Disappearing Male takes a close and disturbing look at what many doctors and researchers now suspect are responsible for many of these problems: a class of common chemicals that are ubiquitous in our world. Found in everything from shampoo, sunglasses, meat and dairy products, carpet, cosmetics and baby bottles, they are called "hormone mimicking" or "endocrine disrupting" chemicals and they may be starting to damage the most basic building blocks of human development. Contact the webmaster  The following form is provided for you to help on the development of this website by sending interesting links, ideas or telling about incidental problems when browsing the site. The message will be sent to the webmaster's mailbox who, eventually, will give you a reply. All fields are mandatory. Recommend this website The following form is provided for you to tell your friends to come and visit Science Helpdesk. All fields are mandatory. About Science Helpdesk is a website meant to help on developing the scientific contents of the Bilingual Project Integrated Curriculum designed by the Spanish Ministerio de Educación y Ciencia and the British Council. Science Helpdesk is designed, developed and published by Arturo J. Murias, currently working in the I.E.S. "Eras de Renueva" (León, Spain) as a Science teacher in the Bilingual Project (MEC/BC). This website is in continuous development and currently under construction. This means that (a) you could spot some relevant errors in the rendering of the pages—please use the "Contact" form below to report to the webmaster, (b) that it is not feature complete, and (c) that a few pages are still to come and some sections a bit short of contents. This website is regularly tested in Mozilla Firefox 3 and Internet Explorer 8; it is also often tested in the latest versions of Opera, Safari and Chrome browsers, all of them in Windows. Testing for older browsers is rarely done, though, and using them might result in unexpected display or behaviour defects. Specifically, you are advised to not to use versions 6 or older of Internet Explorer. Parts of this site (specifically photos and videos) are used without permission, but within fair use, for the purposes of education. Copyright of those contents belong to their authors, mentioned where known. The contents created by the author of this website can be freely distributed under the terms of a Creative Commons License. JavaScript code (and so, every animation and visual effect) has been written upon the awesome jQuery library developed by John Resig and the jQuery team. RSS fetching is accomplished through the SimplePie PHP library developed by Ryan Parman, Geoffrey Sneddon and contributors. The icons used here come from a variety of sources, including the Silk Icons icon set created by Mark James. |
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