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    Science

    How can the sky be blue one day and stormy the next? Why do heavy objects tend to fall downwards when dropped? How are birds able to fly (and why can’t I do the same?)? Human beings have long been curious about the world in which we live, striving to identify connections among the phenomenons we witness and to understand how it all works. The field of science has developed over many centuries as a way of studying and understanding the world, beginning with the primitive stage of simply noting important regularities in nature and continuing through the rise of modern science. The modern-day sciences cover a vast range of fields, including biology, chemistry, meteorology, astronomy, physics, and much more.
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    Featured content, May 22, 2020

    How Albert Einstein Developed the Theory of General Relativity
    Learn how one of history’s greatest minds came up with one of science’s most important theories.
    Companion / Science
    Albert Einstein
    Do Plants Have Sexes?
    Are plants male or female? Does that question even make sense?
    Demystified / Science
    Roses flowers plant colorful rose
    The 1916 Shark Attacks That Gave Sharks a Bad Rap
    How humans and sharks became mortal enemies over the course of two weeks.
    #WTFact / Science
    Great White Shark
    Hell in a Handbag
    Toy and teacup dogs endure horrible congenital disorders to gratify uninformed consumers and unscrupulous breeders.
    Spotlight / Science
    puppy in basket (pup, dog, cute, pet)
    9 of the World’s Deadliest Mammals
    They’re not all soft and cuddly.
    List / Science
    Ruminant. Deer. Red deer. Cervus elaphus. Buck. Stag. Antlers.
    Gedankenexperiment
    Gedankenexperiment, (German: “thought experiment”) term used by German-born physicist Albert Einstein to describe his unique…
    Encyclopedia / Science
    Philosophy of science
    Philosophy of science, the study, from a philosophical perspective, of the elements of scientific inquiry. This article discusses…
    Encyclopedia / Science
    Aristotle
    Evolution
    Evolution, theory in biology postulating that the various types of plants, animals, and other living things on Earth have…
    Encyclopedia / Science
    The geologic time scale from 650 million years ago to the present, showing major evolutionary events.

    Science Quizzes

    View of the Andromeda Galaxy (Messier 31, M31).
    Astronomy and Space Quiz
    What makes a planet a "dwarf" planet? How many miles are in a light-year? What exactly is a quasar? Launch into other worlds…
    Garden spider web with captured prey.
    Insects & Spiders: Fact or Fiction?
    Insects and spiders are fascinating, from delicate butterflies to dancing honeybees and fuzzy tarantulas. But how much do…
    Adult and baby orangutans (Pongo pygmaeus) - (note: probably taken in a zoo).
    Mammals Quiz
    Horses and Hyracotherium and yaks, oh my! Test your knowledge about these amazing animals.
    Dromedary camels (Camelus dromedarius). Animals, mammals.
    Ultimate Animals Quiz
    Could you lead the tour at your city’s zoo? Challenge your animal awareness with this quiz.
    Green tree python snake (Chondropython viridis) in a rainforest.
    Creepy Crawlers Quiz
    Got bugs on the brain? A passion for pests? Test how much you know about insects, snakes, and more.
    Panda bear, daytime, tree, eating, feeding, sitting, nature, giant panda, wildlife, bamboo, Asian, chewing, mammal, daylight, day, Ailuropoda melanoleuca, outdoors, habitat, outside, animal.
    Mammalian Matters: Fact or Fiction?
    Will big horns sink a water buffalo? Is the vampire bat’s thirst for blood bigger than the bat itself? And do orangutans…
    Group of elephant in Africa. Elephants in Africa. Hompepage blog 2009, history and society, geography and travel, explore discovery
    Animals: Fact or Fiction?
    Curiosity may have killed the cat, but kinkajous, bluebacks, and mustelids are alive and well in these questions! They’re…
    Model of a molecule. Atom, Biology, Molecular Structure, Science, Science and Technology. Homepage 2010  arts and entertainment, history and society
    Science Quiz
    Put your science smarts under the microscope and see how much you know about bloodstones, biomes, buoyancy, and more!
    Magnified phytoplankton (pleurosigma angulatum) seen through a microscope, a favorite object for testing the high powers of microscopes. Photomicroscopy. Hompepage blog 2009, history and society, science and technology, explore discovery
    Science: Fact or Fiction?
    Do you get fired up about physics? Giddy about geology? Sort out science fact from fiction with these questions.
    Solar eclipse, 2008.
    Space: Fact or Fiction?
    Mars and the Milky Way are more than just candy bars! See how much more you know about space with this quiz.
    Image Gallery
    Science
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    Science Subcategories

    subcategory placeholder Astronomy
    Human beings have always been fascinated by the celestial sphere above, whose twinkling lights have inspired many theories and artistic endeavors. Study of the solar system has provoked more than just peaceful meditation, however; a major controversy among astronomers arose in the 16th century when Copernicus publicly championed heliocentrism, a Sun-centric model of the solar system that was in direct opposition to Ptolemy's Earth-centered model, which had been generally accepted from the 2nd century CE onward. But humankind's fascination with the world beyond Earth has also led to some landmark moments in history, as when space exploration took a giant step forward with the advent of technology that allowed humans to travel to the Moon and to build spacecraft capable of exploring the rest of the solar system and beyond.
    Articles
    Chordate Biology
    If it’s alive, biology will define it, study it, observe all its functions, follow its vital processes, and interact with it, all in order to understand the life that animates it. In one of biology's best-known examples of such studious investigation, Charles Darwin came up with his scientific theory of evolution by natural selection after systematically observing a variety of plants and animals; his work acted as the foundation upon which modern evolutionary theory is built. But biology’s principles also operate within a plethora of other related fields, including biochemistry, biomedicine, biophysics, and microbiology.
    Articles
    Black girdle-tailed lizard (Cordylus nigra). Birds, Reptiles & Other Vertebrates
    Although it can be hard to imagine that a peacock and a crocodile have much of anything in common, these animals are actually descendants of the same prehistoric vertebrates. Birds are thought to have descended from carnivorous dinosaurs that began growing feathers by the Late Jurassic Period; thus, birds are technically one lineage of reptiles. This evolutionary link highlights the way in which seemingly incongruous creatures can, in fact, share a common ancestor (though that doesn't mean that we should expect waterfowl and crocodiles to become friends anytime soon).
    Articles
    Mantid (Mantis religiosa). Bugs, Mollusks & Other Invertebrates
    Some insects are so displeasing to humans that the word "bug" has come to be used as a verb meaning "to bother or annoy." Yet, in addition to being critically important—because they naturally recycle decaying matter—in maintaining balance within the food chain, bugs can also be fascinating creatures, whether in regard to the water strider's ability to run across the surface of water or in regard to assassin bugs' varied and creative means of catching and killing their prey. Mollusks, another group of invertebrates, get less of a bad rap. Their ranks include nearly 100,000 described species of soft-bodied animals that are usually wholly or partly enclosed in a calcium carbonate shell; examples include snails, clams, oysters, squids, and octopuses.
    Articles
    periodic table Chemistry
    How do you use raw plant materials to manufacture a best-selling perfume? How do you engineer household products that are compliant with environmentally-oriented guidelines? The answers to these questions require an understanding of the laws of chemistry, the science that deals with the properties, composition, and structure of elements and compounds, as well as the transformations that such substances undergo and the energy that is released or absorbed during those processes. Chemistry is also concerned with the utilization of natural substances and the creation of artificial ones. Over time, more than 8,000,000 different chemical substances, both natural and artificial, have been characterized and produced. Chemistry's vast scope comprises organic, inorganic, physical, analytical, and industrial chemistry, along with biochemistry, environmental chemistry, medicinal chemistry, and much more. Through the dedicated efforts of people such as Robert Boyle, Dmitri Mendeleev, John Dalton, Marie Curie, and Rosalind Franklin, the field of chemistry has led to exciting innovations as well as crucial advances in our understanding of how the world functions, starting with just the miniscule and unassuming atom.
    Articles
    subcategory placeholder Earth Science, Geologic Time & Fossils
    Planet Earth has billions of years of history, from the time when it was an inhospitable ball of hot magma to when its surface stabilized into a variety of beautiful and diverse zones capable of supporting many life-forms. Many are the species that lived through the various geologic eras and left a trace of their existence in the fossils that we study today. But Earth is never done settling, as we can see from the earthquakes, tsunamis, volcanic eruptions, and other phenomena manifested in Earth’s crust, oceans, and atmosphere.
    Articles
    Grinnell Glacier shrinkage Environment
    Biological diversity is key to a healthy ecosystem, whether it’s a small biological community or the global biosphere. Ecology, which studies the relationships between organisms and their environment, is an invaluable science that helps us understand what allows an ecological community to thrive.
    Articles
    Meerkat, or suricate (Suricata suricatta). Mammals
    These are the animals to which humans tend to relate the most, perhaps because aspects of their behavior can sometimes resemble the way that we ourselves behave. The protective instinct of a mother bear, the gamboling way that kittens play, and the loyalty displayed by a dog are all traits that we can identify with in the course of our own lives. Mammals are well-equipped to handle different climates and biomes because of their ability to regulate their own body temperatures and internal environment, both in excessive heat and aridity and in severe cold.
    Articles
    An illustration of the difference between average and instantaneous rates of changeThe graph of f(t) shows the secant between (t, f(t)) and (t + h, f(t + h)) and the tangent to f(t) at t. As the time interval  h approaches zero, the secant (average speed) approaches the tangent (actual, or instantaneous, speed) at (t, f(t)). Mathematics
    Although stock portrayals of mathematicians often involve a studious person standing in front of a chalkboard that's covered with mind-bogglingly complex scrawled mathematical problems (call it the "Good Will Hunting" effect), the chaotic-looking equations may obscure the fact that mathematics is, at its heart, a science of structure, order, and relation that deals with logical reasoning and quantitative calculation. There's a method to all that madness! The history of mathematics can be traced back to ancient Mesopotamia, whose clay tablets revealed that the level of mathematical competence was already high as early as roughly the 18th century BCE. Over the centuries, mathematics has evolved from elemental practices of counting, measuring, and describing the shapes of objects into a crucial adjunct to the physical sciences and technology.
    Articles
    photosynthesis Plants
    Life on Earth owes much to plants. The vast majority of plants carry out photosynthesis to transform light energy into chemical energy, which is the way that virtually all energy in the biosphere becomes available to living things (including us humans). As photosynthetic organisms, plants occupy the base of Earth's food webs and are consumed directly or indirectly by all higher life-forms, thereby functioning as the major source of food for humans and other animals. Plants' photosynthetic activity also produces the air that we breathe: almost all the oxygen in the atmosphere is due to the process of photosynthesis. Still not convinced about the merits of plants? Consider the fact that many plants not only serve up crucial nutrients and breathable air but also look good doing it. Many plants are admired for their striking aesthetic qualities, and flowers such as tulips, lilies, sunflowers, and daisies beautify fields, gardens, windowsills, and bouquets the world over. Plants are also a primary source of consumer goods, such as building materials, textile fibers, and pharmaceuticals.
    Articles
    Acoustics Physics
    What’s the matter? The matter is our whole observable universe—with that material substance that constitutes it—and it is the subject of study of physics. The laws that govern motion observed by Newton, the gravitational force that regulates the progress of all celestial bodies, the interaction between subatomic particles, and the nuclear engineering that created the atomic bomb are examples of what this important discipline is all about. Minkowski’s space-time concept, which reformulated Einstein’s special theory of relativity, has bridged physics with philosophy in a conversation that has fascinated the modern concept of physics.
    Articles
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