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Some of our finest [ about ] Approved Articles (0) Developed Articles (1,149) "Knowledge is the true organ of sight, not the eyes." —From the Panchatantra (Indian literature) Article of the Week [ about ] (CC) Photo: Richard Ling This grey nurse shark (Carcharias taurus) and the smaller fish surrounding it are animals. Animals (from the Latin animale and animalis, meaning "living", and anima, meaning "vital breath", or "soul") are those organisms classified into the kingdom Animalia. Together they make up a wide segment of life—biologists estimate their species to number many millions—and include an incredibly diverse array of both familiar and strange creatures, ranging from hawks to humans and from sea slugs to spiders. Nonetheless, they all share certain characteristics: all animals are multicellular eukaryotes, ingest their food, and move by their own power at some point in their life cycle. Animals are essential consumers in many ecosystems and many are also important in human societies and economies.[more...] New Draft of the Week [ about ] Gasoline or petrol is a fuel, derived from petroleum crude oil, for use in spark-ignited internal combustion engines. Conventional gasoline is mostly a blended mixture of more than 200 different hydrocarbon liquids ranging from those containing 4 carbon atoms to those containing 11 or 12 carbon atoms. It has an initial boiling point at atmospheric pressure of about 35 °C (95 °F) and a final boiling point of about 200 °C (395 °F). Gasoline is used primarily as fuel for the internal combustion engines in automotive vehicles as well in some small airplanes. In Canada and the United States, the word "gasoline" is commonly used and it is often shortened to simply "gas" although it is a liquid rather than a gas. In fact, gasoline-dispensing facilities are referred to as "gas stations". Most current or former Commonwealth countries use the term "petrol" and their dispensing facilities are referred to as "petrol stations". The term "petrogasoline" is also used sometimes. In some European countries and elsewhere, the term "benzin" (or a variant of that word) is used to denote gasoline. In aviation, "mogas" (an abbreviation for "motor gasoline") is used to distinguish automotive vehicle fuel from aviation fuel known as "avgas".[more...]