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.

See the disruption wrought by the kudzu vine, which was introduced to the southeastern United States
See the disruption wrought by the kudzu vine, which was introduced to the southeastern United States
Examine the role of sunlight and gravity in phototropic and geotropic plant growth
Examine the role of sunlight and gravity in phototropic and geotropic plant growth
Understand the importance and role of chloroplasts, chlorophyll, grana, thylakoid membranes, and stroma in photosynthesis
Understand the importance and role of chloroplasts, chlorophyll, grana, thylakoid membranes, and stroma in photosynthesis
See how physicist Robert Millikan devised a method for measuring the electric charge of single electrons
See how physicist Robert Millikan devised a method for measuring the electric charge of single electrons
Investigate declines in tiger populations threatened by habitat fragmentation and illegal hunting
Investigate declines in tiger populations threatened by habitat fragmentation and illegal hunting
Observe silky anteaters navigate rainforest treetops with their prehensile tails
Observe silky anteaters navigate rainforest treetops with their prehensile tails
Visit Aymara and Quechua people on the Altiplano of Bolivia and Peru to see the ancient drop-spindle technique
Visit Aymara and Quechua people on the Altiplano of Bolivia and Peru to see the ancient drop-spindle technique
Witness the beauty of various flower blossoms blooming
Witness the beauty of various flower blossoms blooming
Examine the ecologic importance, life cycle, and anatomical structures of the freshwater crustaceans Daphnia
Examine the ecologic importance, life cycle, and anatomical structures of the freshwater crustaceans Daphnia
Witness snowflake crystals created in a laboratory environment
Witness snowflake crystals created in a laboratory environment
Consider the theory of isostasy as an explanation for landforms and the geologic cycle
Consider the theory of isostasy as an explanation for landforms and the geologic cycle
Discover the importance of Sputnik, Yuri Gagarin, Apollo 11, the Hubble Space Telescope, and SpaceShipOne
Discover the importance of Sputnik, Yuri Gagarin, Apollo 11, the Hubble Space Telescope, and SpaceShipOne
Study DNA's double-helix structure, nitrogenous bases, nucleotides, sugar molecules, and phosphate groups
Study DNA's double-helix structure, nitrogenous bases, nucleotides, sugar molecules, and phosphate groups
Discover the nightmarish reproductive habits of the world's largest wasps with the most painful stings
Discover the nightmarish reproductive habits of the world's largest wasps with the most painful stings
Study spore-producing liverworts and their anatomic features such as gametes, thalli, and rhizoids
Study spore-producing liverworts and their anatomic features such as gametes, thalli, and rhizoids
Learn how hermaphroditic coral reproduces once a year after a full moon in good water conditions
Learn how hermaphroditic coral reproduces once a year after a full moon in good water conditions
Observe a single mature cell splitting into two duplicate daughter cells
Observe a single mature cell splitting into two duplicate daughter cells
Watch cress seeds absorb water to catalyze the metabolic activity involved in germination
Watch cress seeds absorb water to catalyze the metabolic activity involved in germination
Consider what makes the Komodo dragon's bite lethal and explore its Indonesian habitat
Consider what makes the Komodo dragon's bite lethal and explore its Indonesian habitat
Learn how the world's largest rodent escapes jaguars, anacondas, and human predators
Learn how the world's largest rodent escapes jaguars, anacondas, and human predators
Study chemistry's periodic law to understand elements' properties and how they relate to one another
Study chemistry's periodic law to understand elements' properties and how they relate to one another
Observe subadult cypris and adult barnacles using cirri retractile organs to collect food particles
Observe subadult cypris and adult barnacles using cirri retractile organs to collect food particles
Examine how llamas serve as pack animals and wool sources in highlands of Bolivia, Chile, and Peru
Examine how llamas serve as pack animals and wool sources in highlands of Bolivia, Chile, and Peru
Follow the history of U.S. spaceflight from Pres. John F. Kennedy to Neil Armstrong and Apollo 11
Follow the history of U.S. spaceflight from Pres. John F. Kennedy to Neil Armstrong and Apollo 11
Study the courtship practices of these flightless ratites and watch a mother ostrich care for its young
Study the courtship practices of these flightless ratites and watch a mother ostrich care for its young
Understand the various phenomena of solar, lunar, and annular eclipses
Understand the various phenomena of solar, lunar, and annular eclipses
Learn how igneous, sedimentary, and metamorphic rock become one another in the rock cycle
Learn how igneous, sedimentary, and metamorphic rock become one another in the rock cycle
Examine the habitat and life cycle of the lungless red salamander amphibian from the Plethodontidae family
Examine the habitat and life cycle of the lungless red salamander amphibian from the Plethodontidae family
Learn about the characteristics, reproductive habits, and different species of seahorses
Learn about the characteristics, reproductive habits, and different species of seahorses
Learn how the Richter scale relies on vibration to logarithmically track earth tremors
Learn how the Richter scale relies on vibration to logarithmically track earth tremors
Learn how chemical reactions are balanced through the metaphor of making change
Learn how chemical reactions are balanced through the metaphor of making change
Watch a time-lapse video of a total lunar eclipse and learn how the Moon's orbit prevents monthly eclipses
Watch a time-lapse video of a total lunar eclipse and learn how the Moon's orbit prevents monthly eclipses
Discover how much nitrogen, oxygen, water vapour, carbon dioxide, and other elements constitute Earth's air
Discover how much nitrogen, oxygen, water vapour, carbon dioxide, and other elements constitute Earth's air
Behold the multitude of Amazonian arthropods including spiders, scorpions, beetles, and mantids
Behold the multitude of Amazonian arthropods including spiders, scorpions, beetles, and mantids
Study the place of sedimentary rock in the rock cycle and how geologists classify such geologic formations
Study the place of sedimentary rock in the rock cycle and how geologists classify such geologic formations
Observe a pocket gopher using its front teeth and foreclaws to burrow a home full of roots, stems, and tubers
Observe a pocket gopher using its front teeth and foreclaws to burrow a home full of roots, stems, and tubers
Observe sea star reproduction, from egg and sperm release and fertilization to development of zooplankton embryos and larvae
Observe sea star reproduction, from egg and sperm release and fertilization to development of zooplankton embryos and larvae
Meet a 2,000-pound leatherback sea turtle and the pair of Russian tortoises that traveled to the Moon
Meet a 2,000-pound leatherback sea turtle and the pair of Russian tortoises that traveled to the Moon
Investigate how the growth pattern of a mushroom spore's hyphae creates a fairy ring
Investigate how the growth pattern of a mushroom spore's hyphae creates a fairy ring
Study the evaporation process of water from Earth's surface into the sky where water vapour forms clouds
Study the evaporation process of water from Earth's surface into the sky where water vapour forms clouds
Investigate how muscles in the body wall and small bristles enable earthworms to move through soil
Investigate how muscles in the body wall and small bristles enable earthworms to move through soil
See how Love waves travel near the surface of a solid medium of varying vertical elasticity
See how Love waves travel near the surface of a solid medium of varying vertical elasticity
Uncover the geologic history of the Grand Canyon stretching back to the Archean Eon
Uncover the geologic history of the Grand Canyon stretching back to the Archean Eon
Track the process of ecological succession from weeds to towering oaks and hickories in a climax community
Track the process of ecological succession from weeds to towering oaks and hickories in a climax community
Follow water as it cycles through the air, land, lakes and rivers, and oceans
Follow water as it cycles through the air, land, lakes and rivers, and oceans
Learn about female and male pine cones and their roles in pine tree reproduction
Learn about female and male pine cones and their roles in pine tree reproduction
Study bacteria's role in organic decomposition, from forest floors to landfills and wastewater-treatment plants
Study bacteria's role in organic decomposition, from forest floors to landfills and wastewater-treatment plants
Explore the mechanics of the lungs and rib and diaphragm muscles involved in human respiration
Explore the mechanics of the lungs and rib and diaphragm muscles involved in human respiration
Discover how heat from Earth's core creates convection currents that cause crustal plates to shift
Discover how heat from Earth's core creates convection currents that cause crustal plates to shift
Study how sieve plates and suction-cupped tube feet enable sea stars to catch prey and move through water
Study how sieve plates and suction-cupped tube feet enable sea stars to catch prey and move through water
Watch a Herpestes mongoose attack and kill its common prey, a venomous Asian cobra
Watch a Herpestes mongoose attack and kill its common prey, a venomous Asian cobra
Witness crop destruction by hail and examine a hailstone's interior under polarized light
Witness crop destruction by hail and examine a hailstone's interior under polarized light
Uncover interesting tidbits about the flightless kakapo, the African gray parrot, and blue and gold macaws
Uncover interesting tidbits about the flightless kakapo, the African gray parrot, and blue and gold macaws
Behold Saguaro National Park plant life. such as the saguaro cactus, unique to the Sonoran Desert
Behold Saguaro National Park plant life. such as the saguaro cactus, unique to the Sonoran Desert
Study adaptations evolved by bryophytic mosses, hornworts, and liverworts and those of vascular angiosperms
Study adaptations evolved by bryophytic mosses, hornworts, and liverworts and those of vascular angiosperms
Watch buildings crumble during the volcanic eruption of Italy's Mount Vesuvius in 1944
Watch buildings crumble during the volcanic eruption of Italy's Mount Vesuvius in 1944
Study the different ways mushrooms release spores and watch mold hyphae spread across bread
Study the different ways mushrooms release spores and watch mold hyphae spread across bread
Observe how an Anglerfish uses its unique anatomy to imitate a wriggling worm to lure in prey
Observe how an Anglerfish uses its unique anatomy to imitate a wriggling worm to lure in prey
Learn how Indo-Pacific lionfish species have become invasive in ecosystems around the globe
Learn how Indo-Pacific lionfish species have become invasive in ecosystems around the globe
Realize the contributions of Mary Somerville to the fields of astronomy, geography, physics, and meteorology
Realize the contributions of Mary Somerville to the fields of astronomy, geography, physics, and meteorology
Study how melanocytes produce skin-darkening melanin and the dangers of long exposure to sunlight
Study how melanocytes produce skin-darkening melanin and the dangers of long exposure to sunlight
Consider how a single-celled organism contains the necessary structures to eat, grow, and reproduce
Consider how a single-celled organism contains the necessary structures to eat, grow, and reproduce
Watch living epidermal cells near the dermis push old cells toward the skin surface to die and become keratin protein
Watch living epidermal cells near the dermis push old cells toward the skin surface to die and become keratin protein
Understand the difference between meteors, meteoroids, and meteorites
Understand the difference between meteors, meteoroids, and meteorites
Observe the aggressive social behaviour of territorial perciform jawfish fighting over burrow proximity
Observe the aggressive social behaviour of territorial perciform jawfish fighting over burrow proximity
Analyze how light affects plants' uptake of carbon dioxide and emission of oxygen
Analyze how light affects plants' uptake of carbon dioxide and emission of oxygen
Understand global warming as a factor in the decline of dissolved oxygen in the ocean
Understand global warming as a factor in the decline of dissolved oxygen in the ocean
See how sieve tubes and sieve plates stimulate mass flow within a plant's phloem cells
See how sieve tubes and sieve plates stimulate mass flow within a plant's phloem cells
Study the unique evolution of species adaptions and biological diversity in the Galapagos Islands
Study the unique evolution of species adaptions and biological diversity in the Galapagos Islands
Learn how deforestation in Central American countries like Belize gives way to erosion and poverty
Learn how deforestation in Central American countries like Belize gives way to erosion and poverty
Learn how the Brazilian government incentivized forest clearing in the Amazon for beef production and ranching
Learn how the Brazilian government incentivized forest clearing in the Amazon for beef production and ranching
Investigate the magnetlike ionic bond formed when electrons transfer from one atom to another
Investigate the magnetlike ionic bond formed when electrons transfer from one atom to another
Take an in-depth look at the variety of plankton, from diatoms and microflagellates to jellyfish
Take an in-depth look at the variety of plankton, from diatoms and microflagellates to jellyfish
Study how the Sun's gravitational pull keeps Earth in a nearly circular orbit
Study how the Sun's gravitational pull keeps Earth in a nearly circular orbit
Consider how Isaac Newton's discovery of gravity led to a better understanding of planetary motion
Consider how Isaac Newton's discovery of gravity led to a better understanding of planetary motion
Watch a silica glass preform heated by a furnace be turned into an optical fibre
Watch a silica glass preform heated by a furnace be turned into an optical fibre
Know the various melon and gourd species, such as the summer favourite watermelon and the natural sponge loofah
Know the various melon and gourd species, such as the summer favourite watermelon and the natural sponge loofah
Understand the difference between poisonous and venomous animals with various examples
Understand the difference between poisonous and venomous animals with various examples
Watch a caterpillar larva eat milkweed, form a pupa, and emerge as a monarch butterfly
Watch a caterpillar larva eat milkweed, form a pupa, and emerge as a monarch butterfly
Compare toothed whales' high-frequency echolocation to baleen whales' low-frequency communication
Compare toothed whales' high-frequency echolocation to baleen whales' low-frequency communication
Use the Punnett square to track dominant and recessive allele pairings that make up a trait's genotype
Use the Punnett square to track dominant and recessive allele pairings that make up a trait's genotype
Study the impact of greenhouse-gas emissions on Earth's temperature and sea levels
Study the impact of greenhouse-gas emissions on Earth's temperature and sea levels
Observe an Eciton army ant colony migrating by night and forming a bivouac nest entirely out of themselves
Observe an Eciton army ant colony migrating by night and forming a bivouac nest entirely out of themselves
Study cheetahs playing and grooming one another before hunting gazelle herd
Study cheetahs playing and grooming one another before hunting gazelle herd
Discern between body and surface waves, primary and secondary waves, and Love and Rayleigh waves
Discern between body and surface waves, primary and secondary waves, and Love and Rayleigh waves
Explore surface tension and how it varies from one liquid to another
Explore surface tension and how it varies from one liquid to another
Try to find brown leaf and leaf-blemish katydids as they mimic their surroundings for camouflage
Try to find brown leaf and leaf-blemish katydids as they mimic their surroundings for camouflage
Test whether solutions formed by ionic or covalent bonds show more electrical resistance
Test whether solutions formed by ionic or covalent bonds show more electrical resistance
Follow alpaca shearing and wool processing and weaving in the Andes
Follow alpaca shearing and wool processing and weaving in the Andes
Study a grasshopper feeding on a leaf and learn how fast a grasshopper cloud can consume a farmer's crops
Study a grasshopper feeding on a leaf and learn how fast a grasshopper cloud can consume a farmer's crops
Follow the nitrogen and phosphorus cycles and learn why farmers fertilize fields to keep them productive
Follow the nitrogen and phosphorus cycles and learn why farmers fertilize fields to keep them productive
Compare Homo habilis, H. erectus, H. neanderthalensis, and H. sapiens to determine the first human species
Compare Homo habilis, H. erectus, H. neanderthalensis, and H. sapiens to determine the first human species
Analyze the structure and motion of cilia and flagella
Analyze the structure and motion of cilia and flagella
See how bacteria recycle forest litter into water, carbon dioxide, nitrogen, and soil minerals
See how bacteria recycle forest litter into water, carbon dioxide, nitrogen, and soil minerals
Watch a tree frog lay eggs, and see through a glass frog's skin to glimpse its inner anatomy
Watch a tree frog lay eggs, and see through a glass frog's skin to glimpse its inner anatomy
Observe a colony of great white egrets eating, flying, and gathering near water
Observe a colony of great white egrets eating, flying, and gathering near water
Observe a brindled gnu herd migrating and grazing followed by zebras, crowned cranes, lions, and hyenas
Observe a brindled gnu herd migrating and grazing followed by zebras, crowned cranes, lions, and hyenas
Study a jellyfish's muscular contractions and learn how the carnivore uses its tentacles to catch prey
Study a jellyfish's muscular contractions and learn how the carnivore uses its tentacles to catch prey
Behold near-boiling water spurting from geysers and hot springs in Wyoming's Yellowstone National Park
Behold near-boiling water spurting from geysers and hot springs in Wyoming's Yellowstone National Park
Witness the sensitive plant's rapid movement when touched, which may be a defense mechanism
Witness the sensitive plant's rapid movement when touched, which may be a defense mechanism
Review how underwater earthquakes, volcanoes, or landslides can generate tsunamis
Review how underwater earthquakes, volcanoes, or landslides can generate tsunamis
Learn about solar-system theories by Aristotle, Ptolemy, Nicolaus Copernicus, and Johannes Kepler
Learn about solar-system theories by Aristotle, Ptolemy, Nicolaus Copernicus, and Johannes Kepler
Learn how annual flowers survive harsh desert conditions and how cacti provide sustenance for wildlife
Learn how annual flowers survive harsh desert conditions and how cacti provide sustenance for wildlife
Follow the trails of leafcutter ants stripping rainforest foliage to cultivate fungus-based food in their nest
Follow the trails of leafcutter ants stripping rainforest foliage to cultivate fungus-based food in their nest
Examine how water held back by Egypt's Aswan High Dam turns turbines to generate electricity
Examine how water held back by Egypt's Aswan High Dam turns turbines to generate electricity
Study the roles of a fish's scales, swim bladder, and gills in its respiratory system
Study the roles of a fish's scales, swim bladder, and gills in its respiratory system
Observe a herd of African savanna elephants forage for food, self-groom, and enjoy a watering hole
Observe a herd of African savanna elephants forage for food, self-groom, and enjoy a watering hole
Follow a beaver family and its kits for a year in the Rocky Mountains and learn about their habits and habitat
Follow a beaver family and its kits for a year in the Rocky Mountains and learn about their habits and habitat
Observe the meiotic reproduction of a diploid cell into four haploid gametes
Observe the meiotic reproduction of a diploid cell into four haploid gametes
Watch an animation of an aquatic dragonfly larva extending its labial mask to catch prey
Watch an animation of an aquatic dragonfly larva extending its labial mask to catch prey
Compare and contrast liverworts and mosses in their reproduction, water absorption, and energy generation
Compare and contrast liverworts and mosses in their reproduction, water absorption, and energy generation
Watch clouds form over the Pacific Ocean and waterfalls pour down Mount Waialeale on the Hawaiian island of Kauai
Watch clouds form over the Pacific Ocean and waterfalls pour down Mount Waialeale on the Hawaiian island of Kauai
Learn about the explosion of a possible comet or asteroid over the Siberian taiga
Learn about the explosion of a possible comet or asteroid over the Siberian taiga
See how cloud formation near a low-pressure system or ongoing tropical storm fuels a hurricane
See how cloud formation near a low-pressure system or ongoing tropical storm fuels a hurricane
Study the effects of increasing concentrations of carbon dioxide on Earth's atmosphere and plant life
Study the effects of increasing concentrations of carbon dioxide on Earth's atmosphere and plant life
Witness a group of mushrooms growing underwater and revealing gills on their caps' undersides
Witness a group of mushrooms growing underwater and revealing gills on their caps' undersides
Go inside a tropical cyclone's eye to learn how low-pressure cores exist amid cloud walls and high winds
Go inside a tropical cyclone's eye to learn how low-pressure cores exist amid cloud walls and high winds
Behold a true beaked whale mother and calf near the Azores and Canary Islands
Behold a true beaked whale mother and calf near the Azores and Canary Islands
Study Earth's daily rotation on its axis and yearly revolution around the Sun
Study Earth's daily rotation on its axis and yearly revolution around the Sun
Explore an atom's interior to discover the layout of its nucleus, protons, and electrons
Explore an atom's interior to discover the layout of its nucleus, protons, and electrons
Examine how earthquake shock waves can generate a tsunami like the one that crashed down on Hilo in 1946
Examine how earthquake shock waves can generate a tsunami like the one that crashed down on Hilo in 1946
See how sea otters maintain the balance of kelp-forest ecosystems by consuming sea urchins
See how sea otters maintain the balance of kelp-forest ecosystems by consuming sea urchins
Discover how the volcanic island of Surtsey formed for ash and lava erupting from the seafloor near Iceland
Discover how the volcanic island of Surtsey formed for ash and lava erupting from the seafloor near Iceland
Observe how radiation from atomic bombs and nuclear disasters remains a major environmental concern
Observe how radiation from atomic bombs and nuclear disasters remains a major environmental concern
Witness the playful gliding and fishing of river otters in a freshly thawed North American river
Witness the playful gliding and fishing of river otters in a freshly thawed North American river
Discern between monocotyledons with single-leaf seed sprouts and eudicotyledons with two-leaf seed sprouts
Discern between monocotyledons with single-leaf seed sprouts and eudicotyledons with two-leaf seed sprouts
Walk through the process of mitotic cell division to understand the foundation of growth
Walk through the process of mitotic cell division to understand the foundation of growth
Long-term data sets reveal increased concentrations of the greenhouse gas carbon dioxide in Earth's atmosphere
Long-term data sets reveal increased concentrations of the greenhouse gas carbon dioxide in Earth's atmosphere
Examine bipedal biomechanics through a skeletal view of a tyrannosaur's stride
Examine bipedal biomechanics through a skeletal view of a tyrannosaur's stride
Observe permanent plankton, including transparent larvaceans, ciliate protozoans, and other zooplankton
Observe permanent plankton, including transparent larvaceans, ciliate protozoans, and other zooplankton
Study how eccrine glands in the dermis secrete sweat through pores in the skin's surface
Study how eccrine glands in the dermis secrete sweat through pores in the skin's surface
Uncover the forces of potential energy, kinetic energy, and friction behind a grandfather clock's pendulum
Uncover the forces of potential energy, kinetic energy, and friction behind a grandfather clock's pendulum
Watch green sea turtles hatch from eggs and head to the ocean to avoid predators
Watch green sea turtles hatch from eggs and head to the ocean to avoid predators
watch a starfish's tube feet pry open a mussel's shell and extrude its stomach onto the mussel
watch a starfish's tube feet pry open a mussel's shell and extrude its stomach onto the mussel
Learn how paired chromosomes composed of mostly DNA determine an organism's heredity
Learn how paired chromosomes composed of mostly DNA determine an organism's heredity
Learn how advancements in the xylem, vascular tissue, and flower separate angiosperms from gymnosperms
Learn how advancements in the xylem, vascular tissue, and flower separate angiosperms from gymnosperms
See how the passionflower ensures cross-pollination
See how the passionflower ensures cross-pollination
Track the discovery of dinosaurs from 7th-century griffin legends to Richard Owen's coining of Dinosauria
Track the discovery of dinosaurs from 7th-century griffin legends to Richard Owen's coining of Dinosauria
Learn how wolves are migrating from Germany back into Denmark after having been exterminated two centuries ago
Learn how wolves are migrating from Germany back into Denmark after having been exterminated two centuries ago
Know the difference between climate and weather and how the slightest climate change can impact life
Know the difference between climate and weather and how the slightest climate change can impact life
Observe a demonstration of how wind energy transferred to water generates waves
Observe a demonstration of how wind energy transferred to water generates waves
Learn how the radiometric rubidium-strontium dating technique is used to determine the age of rock particles
Learn how the radiometric rubidium-strontium dating technique is used to determine the age of rock particles
Watch a marine worm's tentacles emerge from its tube, exposing mucous traps for food particles
Watch a marine worm's tentacles emerge from its tube, exposing mucous traps for food particles
S waves travel through an elastic medium in curved paths and shear the medium in one direction and then another
S waves travel through an elastic medium in curved paths and shear the medium in one direction and then another
Watch as a southern elephant seal pup is startled on the Argentinian coast and hear its snarl
Watch as a southern elephant seal pup is startled on the Argentinian coast and hear its snarl
Explore how interactions between the water cycle and landforms affect climate and weather
Explore how interactions between the water cycle and landforms affect climate and weather
See stalagmites and stalactites formed by carbonite mineral deposits from limestone dissolved by groundwater
See stalagmites and stalactites formed by carbonite mineral deposits from limestone dissolved by groundwater
Observe an anole change its skin colour for camouflage and fan its dewlap to mark possession or attract a mate
Observe an anole change its skin colour for camouflage and fan its dewlap to mark possession or attract a mate
Understand how the presence of different pigments chlorophyll, anthocyanin, anthoxanthins, and carotenoids determine a plant's color
Understand how the presence of different pigments chlorophyll, anthocyanin, anthoxanthins, and carotenoids determine a plant's color
Observe a baboon troop descend from treetops to rove, play, and forage in the Tanzanian landscape
Observe a baboon troop descend from treetops to rove, play, and forage in the Tanzanian landscape
See how Earth's constant axial tilt and yearly revolution around the Sun cause seasons
See how Earth's constant axial tilt and yearly revolution around the Sun cause seasons
Discover how climate change and food scarcity may have caused the megalodon's extinction
Discover how climate change and food scarcity may have caused the megalodon's extinction
Learn how hardy morning glory seeds' redundant genome and flavonoid-rich coats protect them from radiation
Learn how hardy morning glory seeds' redundant genome and flavonoid-rich coats protect them from radiation
Observe a tower of giraffes feeding on acacia leaves and oxpeckers combing giraffes' coats for parasites
Observe a tower of giraffes feeding on acacia leaves and oxpeckers combing giraffes' coats for parasites
Discern between self-sustaining autotrophs and consumer heterotrophs and find their places in the food chain
Discern between self-sustaining autotrophs and consumer heterotrophs and find their places in the food chain
Behold the rattlesnake's rattle, thought to be a warning device to other organisms
Behold the rattlesnake's rattle, thought to be a warning device to other organisms
Learn about the various forms of asexual plant reproduction; bulb, gemma, plantlet, and cutting
Learn about the various forms of asexual plant reproduction; bulb, gemma, plantlet, and cutting
Observe a herd of gazelles grazing, playing, and nursing in their natural habitat on the African plains
Observe a herd of gazelles grazing, playing, and nursing in their natural habitat on the African plains
Study the habits of amoebae, vorticellas, paramecium, and other protozoans under a microscope
Study the habits of amoebae, vorticellas, paramecium, and other protozoans under a microscope
Observe the importance of a mushroom's mycelium in the decomposition of organic matter
Observe the importance of a mushroom's mycelium in the decomposition of organic matter
See how an updraft of warm, unstable air moves the tornado vortex upward in expanding spirals
See how an updraft of warm, unstable air moves the tornado vortex upward in expanding spirals
Observe a giant anteater using its long muzzle and wormlike tongue to eat and drink
Observe a giant anteater using its long muzzle and wormlike tongue to eat and drink
Observe the South American lowland tapir wading in a swamp for food
Observe the South American lowland tapir wading in a swamp for food
Watch a Gila monster raid a nest for eggs
Watch a Gila monster raid a nest for eggs
Watch P waves (primary waves) travel through an elastic medium
Watch P waves (primary waves) travel through an elastic medium
View elephant seals on Argentina's southern coast and Magellan penguins on the country's Valdes Peninsula
View elephant seals on Argentina's southern coast and Magellan penguins on the country's Valdes Peninsula
Brush up on anthers, stigmas, florets, and insects with a self- and cross-pollination guide
Brush up on anthers, stigmas, florets, and insects with a self- and cross-pollination guide
Study how spiders' prodigious predation of herbivorous insects protects plant life
Study how spiders' prodigious predation of herbivorous insects protects plant life
Learn how a hummingbird can fly in any direction and about its iridescent plumage
Learn how a hummingbird can fly in any direction and about its iridescent plumage
Observe a trumpeter swan care for cygnets in their nest and marsh-grass habitat
Observe a trumpeter swan care for cygnets in their nest and marsh-grass habitat
examine a variety of echinoderm species such as starfish, basket star, sand dollar, and sea cucumber
examine a variety of echinoderm species such as starfish, basket star, sand dollar, and sea cucumber
See how John Dalton built his atomic theory on principles laid out by Henry Cavendish and Joseph-Louis Proust
See how John Dalton built his atomic theory on principles laid out by Henry Cavendish and Joseph-Louis Proust
Discern the difference between frequency and amplitude by studying sound waves
Discern the difference between frequency and amplitude by studying sound waves
Discussion with Kara Rogers of how the scientific model is used to test a hypothesis or represent a theory
Discussion with Kara Rogers of how the scientific model is used to test a hypothesis or represent a theory
Learn about explorations of Mars, including spacecraft orbiting the planet and the Opportunity and Curiosity rovers traversing Mars's surface
Learn about explorations of Mars, including spacecraft orbiting the planet and the Opportunity and Curiosity rovers traversing Mars's surface
Explore the Arctic doomsday vault preserving the planet's seeds in the Svalbard archipelago
Explore the Arctic doomsday vault preserving the planet's seeds in the Svalbard archipelago
See molecular bonds at work as two hydrogen atoms join a sulfur atom to make hydrogen sulfide
See molecular bonds at work as two hydrogen atoms join a sulfur atom to make hydrogen sulfide
Learn how a genetic fingerprint is made using agarose gel, Southern blotting, and a radioactive DNA probe
Learn how a genetic fingerprint is made using agarose gel, Southern blotting, and a radioactive DNA probe
Watch a North American raccoon scale a tree to steal eggs from a red-tailed hawk's nest
Watch a North American raccoon scale a tree to steal eggs from a red-tailed hawk's nest
Investigate how honeybees construct combs out of wax to store honey, plant nectar, and bee bread
Investigate how honeybees construct combs out of wax to store honey, plant nectar, and bee bread
Study how bacteriophages replicate by injecting nucleic acid into a bacteria cell to create virions
Study how bacteriophages replicate by injecting nucleic acid into a bacteria cell to create virions
Observe how Rayleigh waves traverse the free surface of an elastic solid such as Earth's surface
Observe how Rayleigh waves traverse the free surface of an elastic solid such as Earth's surface
Learn how dominant and recessive genes determine which traits and offspring will possess
Learn how dominant and recessive genes determine which traits and offspring will possess
Learn how hibernating ground squirrels lower their body temperatures to enter a dormant state
Learn how hibernating ground squirrels lower their body temperatures to enter a dormant state
Understand the spatial relationships between the Sun, the Moon, and Earth during eclipses
Understand the spatial relationships between the Sun, the Moon, and Earth during eclipses
Discover the copepod's place in the marine food chain and how it develops from a larva into an adult
Discover the copepod's place in the marine food chain and how it develops from a larva into an adult
Witness a grasshopper molting as it sheds its outgrown exoskeleton
Witness a grasshopper molting as it sheds its outgrown exoskeleton
Observe effects of smoking on lung tissue and examine various stages of respiratory disease
Observe effects of smoking on lung tissue and examine various stages of respiratory disease
Watch red blood cells travel through arteries and capillaries to deliver oxygen
Watch red blood cells travel through arteries and capillaries to deliver oxygen
Watch a demonstration of Isaac Newton's law of action and reaction as a rocket launches into space
Watch a demonstration of Isaac Newton's law of action and reaction as a rocket launches into space
Consider whether the continuous band of membranous tissue around humans' intestines should be deemed an organ
Consider whether the continuous band of membranous tissue around humans' intestines should be deemed an organ
Learn how purple sulfur bacteria photosynthesize sans oxygen and how myxobacteria decompose forest material
Learn how purple sulfur bacteria photosynthesize sans oxygen and how myxobacteria decompose forest material
Understand the sexual and asexual reproduction from the bramble and the daffodil plant
Understand the sexual and asexual reproduction from the bramble and the daffodil plant
Study the life cycle and fossilization of Carcharocles megalodon from the Miocene and Pliocene epochs
Study the life cycle and fossilization of Carcharocles megalodon from the Miocene and Pliocene epochs
Spot the Andean condor soaring among the Andes mountaintops and note its impressive wingspan
Spot the Andean condor soaring among the Andes mountaintops and note its impressive wingspan
Observe a scarlet macaw using its beak and talons to obtain food
Observe a scarlet macaw using its beak and talons to obtain food
Investigate various types of phytoplankton, their anatomies, and their means of photosynthesis
Investigate various types of phytoplankton, their anatomies, and their means of photosynthesis
Follow the development of rice-paddy fish from fertilization to hatching in a laboratory setting
Follow the development of rice-paddy fish from fertilization to hatching in a laboratory setting
Examine the trophic levels of producers, herbivores, and carnivores in a given ecosystem
Examine the trophic levels of producers, herbivores, and carnivores in a given ecosystem
Examine how a subcutaneous fat layer supplies nutrients to dense connective tissue and epithelial cells
Examine how a subcutaneous fat layer supplies nutrients to dense connective tissue and epithelial cells
Witness a living plant cell's chromosomes carrying genetic material duplicate during the process of mitosis
Witness a living plant cell's chromosomes carrying genetic material duplicate during the process of mitosis
Study dangerous turtles and lizards such as Gila monsters, crocodile monitors, and Komodo dragons
Study dangerous turtles and lizards such as Gila monsters, crocodile monitors, and Komodo dragons
Classify newly formed snow crystals as fernlike stellar dendrites, columns, or needles
Classify newly formed snow crystals as fernlike stellar dendrites, columns, or needles
Inspect a cross-section of dermis and epidermis and see papillae, blood and lymph vessels, muscles, and nerves
Inspect a cross-section of dermis and epidermis and see papillae, blood and lymph vessels, muscles, and nerves
Learn about the structure of chloroplast and its role in photosynthesis
Learn about the structure of chloroplast and its role in photosynthesis
Observe a zebra herd on the African plains and the mutualistic relationship it shares with the oxpecker
Observe a zebra herd on the African plains and the mutualistic relationship it shares with the oxpecker
Follow a female grasshopper as its eggs are fertilized, buried underground, and hatched
Follow a female grasshopper as its eggs are fertilized, buried underground, and hatched
Observe the hagfish's horny teeth and scaleless exterior covering a cartilaginous skeleton
Observe the hagfish's horny teeth and scaleless exterior covering a cartilaginous skeleton
See the black skimmer water bird skim the calm surface with its longer lower mandible in search of prey
See the black skimmer water bird skim the calm surface with its longer lower mandible in search of prey
Understand how cell membranes regulate food consumption and waste and how cell walls provide protection
Understand how cell membranes regulate food consumption and waste and how cell walls provide protection
Observe flamingo flight, flocking, and feeding behaviours
Observe flamingo flight, flocking, and feeding behaviours
Dissect a chloroplast and identify its stroma, thylakoids, and chlorophyll-packed grana
Dissect a chloroplast and identify its stroma, thylakoids, and chlorophyll-packed grana
Learn five facts about the astronomical phenomenon that occurs when the Moon passes between the Sun and Earth
Learn five facts about the astronomical phenomenon that occurs when the Moon passes between the Sun and Earth
Uncover Alfred Wegener's theory of continental drift through biological and geological evidence and the theory of plate tectonics
Uncover Alfred Wegener's theory of continental drift through biological and geological evidence and the theory of plate tectonics
Observe chimpanzees' social interactions in their rainforest, grassland, and woodland habitats
Observe chimpanzees' social interactions in their rainforest, grassland, and woodland habitats
Investigate varying electron configurations in electron shells around an atom's nucleus
Investigate varying electron configurations in electron shells around an atom's nucleus
Understand the relationship between a society's development and the management of its mineral resources
Understand the relationship between a society's development and the management of its mineral resources
See a golden eagle take flight from its nest to swoop down on rabbit prey
See a golden eagle take flight from its nest to swoop down on rabbit prey
Consider the amount of physical and educational training necessary to become an astronaut
Consider the amount of physical and educational training necessary to become an astronaut
Examine how Falco peregrinus uses controlled falls and outstretched talons to prey on pigeons and ducks
Examine how Falco peregrinus uses controlled falls and outstretched talons to prey on pigeons and ducks
Observe a chameleon's zygodactylous feet, acrodont dentition, independent eyes, and projectile tongue at work
Observe a chameleon's zygodactylous feet, acrodont dentition, independent eyes, and projectile tongue at work
Discover how the pilot black snake utilizes its ventral scales to glide through water, land, and trees
Discover how the pilot black snake utilizes its ventral scales to glide through water, land, and trees
Examine what separates mushrooms, mildews, molds, and yeasts from the plant and animal kingdoms
Examine what separates mushrooms, mildews, molds, and yeasts from the plant and animal kingdoms
Observe a land iguana, its burrow, and its herbivorous diet of cactus flowers, roots, and stems
Observe a land iguana, its burrow, and its herbivorous diet of cactus flowers, roots, and stems
Witness an orb-weaving spider using silk wrappings to immobilize grasshopper prey
Witness an orb-weaving spider using silk wrappings to immobilize grasshopper prey
Know why suction cups do not work in outer space
Know why suction cups do not work in outer space
Glimpse Amazonian wildlife, including birds, mammals, and reptiles
Glimpse Amazonian wildlife, including birds, mammals, and reptiles
Discover how astronauts mimic space's microgravity on Earth with a special plane and a ballistic flight path
Discover how astronauts mimic space's microgravity on Earth with a special plane and a ballistic flight path
Examine a rag worm crawling in sand and a close-up of its gills
Examine a rag worm crawling in sand and a close-up of its gills
Tour the Pampas to catch sight of a giant anteater, crab-eating fox, and pampas deer
Tour the Pampas to catch sight of a giant anteater, crab-eating fox, and pampas deer
Examine habits of lemmings and dangers they face during migration, such as predation, starvation, and accidents
Examine habits of lemmings and dangers they face during migration, such as predation, starvation, and accidents
See samples of what is possibly soft tissue discovered in a Lufengosaurus fossil from the Jurassic Period
See samples of what is possibly soft tissue discovered in a Lufengosaurus fossil from the Jurassic Period
Learn how phytoplankton supply oxygen via photosynthesis and serve as the first link in the marine food chain
Learn how phytoplankton supply oxygen via photosynthesis and serve as the first link in the marine food chain
Witness the praying mantis's predatory feeding habits and learn about the insect's sexual cannibalism
Witness the praying mantis's predatory feeding habits and learn about the insect's sexual cannibalism
Study how Ptolemy tried to use deferents and epicycles to explain retrograde motion
Study how Ptolemy tried to use deferents and epicycles to explain retrograde motion
Watch a velvet worm, an ancient terrestrial invertebrate, crawl across leaf litter
Watch a velvet worm, an ancient terrestrial invertebrate, crawl across leaf litter
Learn how the Andes Mountains block warm moist air, causing heavy rainfall that feeds the Amazon River
Learn how the Andes Mountains block warm moist air, causing heavy rainfall that feeds the Amazon River
Watch a pika forage for food in mountainous terrain and deliver a litter of fully dependent hairless pups
Watch a pika forage for food in mountainous terrain and deliver a litter of fully dependent hairless pups
Consider the whooping crane's migratory patterns and how the human population has contributed to the destruction of its habitat
Consider the whooping crane's migratory patterns and how the human population has contributed to the destruction of its habitat
Explore the adaptions of ray-finned fish species such as seahorses, filefish, jawfish, pipefish, and boxfish
Explore the adaptions of ray-finned fish species such as seahorses, filefish, jawfish, pipefish, and boxfish
Follow hormones of the endocrine system from glands to their chemical receptors on or in a cell
Follow hormones of the endocrine system from glands to their chemical receptors on or in a cell
Meet longhair cat breeds from Balinese and Cymric to Javanese and Norwegian Forest cats
Meet longhair cat breeds from Balinese and Cymric to Javanese and Norwegian Forest cats
See the poisonous squirting cucumber eject mucilage-covered seeds
See the poisonous squirting cucumber eject mucilage-covered seeds
Determine the chemical composition of Earth's atmosphere and discover the forces behind wind patterns
Determine the chemical composition of Earth's atmosphere and discover the forces behind wind patterns
Study the long-lived Greenland sharks inhabiting the Arctic Ocean and North Atlantic
Study the long-lived Greenland sharks inhabiting the Arctic Ocean and North Atlantic
Study the distinctive characteristics of the North American timber tulip tree of the magnolia family
Study the distinctive characteristics of the North American timber tulip tree of the magnolia family
Observe flightless cormorants in their natural habitat on coasts of Fernandina and Isabela islands
Observe flightless cormorants in their natural habitat on coasts of Fernandina and Isabela islands
Find out what an organism is and consider which one is the world's smallest
Find out what an organism is and consider which one is the world's smallest
Observe the human immune response phagocytosis, in which leukocytes ingest or engulf invading microscopic organisms or particles
Observe the human immune response phagocytosis, in which leukocytes ingest or engulf invading microscopic organisms or particles
Discover how ecotourism at Monteverde Cloud Forest Biological Reserve aids conservation
Discover how ecotourism at Monteverde Cloud Forest Biological Reserve aids conservation
Delve into a chloroplast's stroma to watch adenosine triphosphate provide energy for sugar-producing reactions
Delve into a chloroplast's stroma to watch adenosine triphosphate provide energy for sugar-producing reactions
Zoom out from Earth's solar system to the Milky Way Galaxy, the Local Group, and beyond
Zoom out from Earth's solar system to the Milky Way Galaxy, the Local Group, and beyond
Track the development of a human being from embryo to fetus to newborn
Track the development of a human being from embryo to fetus to newborn
Observe flocks of masked, red-footed, and blue-footed booby species common to the Galápagos coasts
Observe flocks of masked, red-footed, and blue-footed booby species common to the Galápagos coasts
View an Icelandic waterfall and learn about its geologic life cycle and erosion into a smooth riverbed
View an Icelandic waterfall and learn about its geologic life cycle and erosion into a smooth riverbed
Learn how scientists use time-lapse photography to track movement and flow of glaciers
Learn how scientists use time-lapse photography to track movement and flow of glaciers
Listen to a humpback whale pod communicate via underwater “songs”
Listen to a humpback whale pod communicate via underwater “songs”
Witness a crocodile hatchling emerge from its egg and hear the newborn call for its mother
Witness a crocodile hatchling emerge from its egg and hear the newborn call for its mother
Watch a diver while learning how the cerebellum helps maintain muscle tone, posture, and equilibrium
Watch a diver while learning how the cerebellum helps maintain muscle tone, posture, and equilibrium
Examine the differences in structure and function of endoskeletons and exoskeletons
Examine the differences in structure and function of endoskeletons and exoskeletons
Observe a total solar eclipse as the Moon passes between the Sun and Earth
Observe a total solar eclipse as the Moon passes between the Sun and Earth
See how differing amounts of solar radiation at the poles and Equator affect Earth's climate and atmosphere
See how differing amounts of solar radiation at the poles and Equator affect Earth's climate and atmosphere
Learn how the angiosperm and gymnosperm plants store their seeds
Learn how the angiosperm and gymnosperm plants store their seeds
Discover how a fern employs its vascular system to circulate water and nutrients between its leaves and roots
Discover how a fern employs its vascular system to circulate water and nutrients between its leaves and roots
Glimpse Amazonian wildlife such as anacondas, tarantulas, leafcutter ants, scarlet ibis, and black skimmers
Glimpse Amazonian wildlife such as anacondas, tarantulas, leafcutter ants, scarlet ibis, and black skimmers
Investigate the role of water in erosion and in the greater geologic rock cycle
Investigate the role of water in erosion and in the greater geologic rock cycle
See toads engage in amphibious amplexus and witness metamorphosis of tadpoles into toads
See toads engage in amphibious amplexus and witness metamorphosis of tadpoles into toads
Discover Magellanic penguins' namesake and see them gathering to breed on Valdés Peninsula, Argentina
Discover Magellanic penguins' namesake and see them gathering to breed on Valdés Peninsula, Argentina
Examine the application of Werner Heisenberg's uncertainty principle of subatomic particles
Examine the application of Werner Heisenberg's uncertainty principle of subatomic particles
Observe the action of a magnetic field and interactions between magnetic poles
Observe the action of a magnetic field and interactions between magnetic poles
Learn how invasive species and habitat destruction have threatened Hawaii's yellow-faced bees
Learn how invasive species and habitat destruction have threatened Hawaii's yellow-faced bees
Discover diffraction as a property of sound, electromagnetic radiation, and small moving particles
Discover diffraction as a property of sound, electromagnetic radiation, and small moving particles
Explore the nascent industry of space tourism, in which people pay to be launched into space
Explore the nascent industry of space tourism, in which people pay to be launched into space
Learn how the Richter scale measures magnitude and the Mercalli scale measures intensity of an earthquake
Learn how the Richter scale measures magnitude and the Mercalli scale measures intensity of an earthquake
See how astronauts train on parabolic fights to prepare for the weightlessness experienced in space
See how astronauts train on parabolic fights to prepare for the weightlessness experienced in space
Study how marine iguanas live on the coasts of the Galapagos Islands and survive on seaweeds
Study how marine iguanas live on the coasts of the Galapagos Islands and survive on seaweeds
Consider Jakob Steiner's Roman surface in which each tangent plane intersects the surface in a pair of conics
Consider Jakob Steiner's Roman surface in which each tangent plane intersects the surface in a pair of conics
Discover the International Astronomical Union's naming schemes for features on Pluto and its moons
Discover the International Astronomical Union's naming schemes for features on Pluto and its moons
Watch a suspended vibrating spring to learn about the propagation of sound waves
Watch a suspended vibrating spring to learn about the propagation of sound waves
Learn about P waves, S waves, Love waves, and Rayleigh waves generated by an earthquake
Learn about P waves, S waves, Love waves, and Rayleigh waves generated by an earthquake
Follow a sea plow burying a fibre optic cable with repeaters for efficient information transmission
Follow a sea plow burying a fibre optic cable with repeaters for efficient information transmission
Examine stained images distinguishing phagocytes from bacteria during phagocytosis
Examine stained images distinguishing phagocytes from bacteria during phagocytosis
Examine metagenesis and the roles of antheridia, archegonia, and the sporangium in the moss Mnium hornum
Examine metagenesis and the roles of antheridia, archegonia, and the sporangium in the moss Mnium hornum
Learn how flowers use secreted nectar, scent, and appearance to attract cross-pollinating bees
Learn how flowers use secreted nectar, scent, and appearance to attract cross-pollinating bees
Watch a doe give birth to a pair of fawns and then care for them and guide them
Watch a doe give birth to a pair of fawns and then care for them and guide them
Consider how the invention of the microscope abetted the discovery and categorization of cells
Consider how the invention of the microscope abetted the discovery and categorization of cells
Explore how plastic is recycled into insulation and other building materials
Explore how plastic is recycled into insulation and other building materials
Study how magma erupts as lava and turns into pumice or hardens to form a shield volcano
Study how magma erupts as lava and turns into pumice or hardens to form a shield volcano
Discover how individual cilia employ viscous drag to coordinate power and recovery strokes for locomotion
Discover how individual cilia employ viscous drag to coordinate power and recovery strokes for locomotion
Follow a burrowing earthworm seeking soil's moisture to protect its oxygen-collecting skin
Follow a burrowing earthworm seeking soil's moisture to protect its oxygen-collecting skin
Examine Aristotle's model of the solar system and note its failure to explain phenomena like retrograde motion
Examine Aristotle's model of the solar system and note its failure to explain phenomena like retrograde motion
Witness the bullfrog's powerful action, generated by its hind legs, as it jumps through a field
Witness the bullfrog's powerful action, generated by its hind legs, as it jumps through a field
Understand how roots and leaves transport oxygen, carbon dioxide, and minerals vital to a plant's development
Understand how roots and leaves transport oxygen, carbon dioxide, and minerals vital to a plant's development
Behold a time-lapse video of a mushroom cap's emergence from the ground
Behold a time-lapse video of a mushroom cap's emergence from the ground
Encounter some of the 20,000 legume species from vines and trees to shrubs and herbs
Encounter some of the 20,000 legume species from vines and trees to shrubs and herbs
Examine glacial scratches on rocks from Switzerland to New York City for evidence of Earth's icy past
Examine glacial scratches on rocks from Switzerland to New York City for evidence of Earth's icy past
Observe protozoan microorganisms from a drop of pond water under optical and electron microscopes
Observe protozoan microorganisms from a drop of pond water under optical and electron microscopes
Learn how the predatory pilot black snake strikes, suffocates, and consumes whole its rodent prey
Learn how the predatory pilot black snake strikes, suffocates, and consumes whole its rodent prey
Watch how a queen triggerfish defeats a sea urchin's defensive tactics
Watch how a queen triggerfish defeats a sea urchin's defensive tactics
Discover how water moves through plants, including osmosis and transpiration
Discover how water moves through plants, including osmosis and transpiration
Divide into four phases the reproduction process of chromosomes in plant and animal cells
Divide into four phases the reproduction process of chromosomes in plant and animal cells
See how diversity of cichlid species in Lake Nyasa compares with finch diversity in the Galapagos Islands
See how diversity of cichlid species in Lake Nyasa compares with finch diversity in the Galapagos Islands
Discover why an object will float or sink
Discover why an object will float or sink
Discover how glucose and oxygen produced during photosynthesis in plants helps during respiration in animals
Discover how glucose and oxygen produced during photosynthesis in plants helps during respiration in animals
Glimpse the Amazon Rainforest's diverse wildlife, from anacondas and sloths to macaws and capybaras
Glimpse the Amazon Rainforest's diverse wildlife, from anacondas and sloths to macaws and capybaras
View a time-lapse video of cloud formations rolling across the sky followed by a thunderstorm
View a time-lapse video of cloud formations rolling across the sky followed by a thunderstorm
Study an amphibious tiger salamander of the mole salamander family Ambystomatidae in its natural habitat
Study an amphibious tiger salamander of the mole salamander family Ambystomatidae in its natural habitat
Examine how bacteria can be beneficial ecological agents of decomposition but harmful spoilers of food and agents of disease
Examine how bacteria can be beneficial ecological agents of decomposition but harmful spoilers of food and agents of disease
Examine the relationship between Northern fur seal cows and their pups and see how pups learn to swim
Examine the relationship between Northern fur seal cows and their pups and see how pups learn to swim
Classify volcanic eruptions according to the physical and chemical properties of their magma
Classify volcanic eruptions according to the physical and chemical properties of their magma
Explore the anatomy of a plant's mesophyll to understand how chlorophyll generates a green appearance
Explore the anatomy of a plant's mesophyll to understand how chlorophyll generates a green appearance
See time-lapse microphotography of blastomeres created by mitotic cleavage of embryonic cells
See time-lapse microphotography of blastomeres created by mitotic cleavage of embryonic cells
See how enzymes in wax moth larva could lead to new recycling biotechnologies
See how enzymes in wax moth larva could lead to new recycling biotechnologies
Watch a banded sand snake seem to swim under sand and a sidewinder snake sidewinding across the desert floor
Watch a banded sand snake seem to swim under sand and a sidewinder snake sidewinding across the desert floor
Classify colors on the visible spectrum of electromagnetic radiation by hue, saturation, and brightness
Classify colors on the visible spectrum of electromagnetic radiation by hue, saturation, and brightness
Examine the various changes undergone by an elk's coat from winter to summer and from nursing calves to adults who eventually separate to form new herds
Examine the various changes undergone by an elk's coat from winter to summer and from nursing calves to adults who eventually separate to form new herds
Study a prairie dog colony, breeding habits, and response to predators in the North American plains
Study a prairie dog colony, breeding habits, and response to predators in the North American plains
Compare the Rafflesia arnoldii's massive bloom with Amorphophallus titanum's towering inflorescence
Compare the Rafflesia arnoldii's massive bloom with Amorphophallus titanum's towering inflorescence
Learn how resistance affects the flow of electrons in an electric circuit
Learn how resistance affects the flow of electrons in an electric circuit
Study the North American toad's projectile tongue in real time and slow motion as it catches insect prey
Study the North American toad's projectile tongue in real time and slow motion as it catches insect prey
Observe how the sporophytic fern appears to unfurl upward as it grows from its rhizome
Observe how the sporophytic fern appears to unfurl upward as it grows from its rhizome
Discern between umbra and penumbra, partial and total eclipses, and solar and annular eclipses
Discern between umbra and penumbra, partial and total eclipses, and solar and annular eclipses
Observe in slow motion how North American toads change the potential energy in their hind legs to kinetic energy to power their leaps
Observe in slow motion how North American toads change the potential energy in their hind legs to kinetic energy to power their leaps
See how the xylem carries food up from the roots and how the phloem transports food down from the leaves
See how the xylem carries food up from the roots and how the phloem transports food down from the leaves
Follow a Bacillus subtilis colony as it goes through the lag, log, stationary, and death phases of growth
Follow a Bacillus subtilis colony as it goes through the lag, log, stationary, and death phases of growth
Watch clouds transforming into tornadoes
Watch clouds transforming into tornadoes
Glimpse the diversity of plant evolution that provides food and habitats for other life to thrive
Glimpse the diversity of plant evolution that provides food and habitats for other life to thrive
Take a microscopic look at how a eukaryotic flagellate's flagellum propels the organism through water
Take a microscopic look at how a eukaryotic flagellate's flagellum propels the organism through water
See how Edwin Hubble, Georges Lemaître, Arno Penzias, and Robert Wilson contributed to the big-bang model
See how Edwin Hubble, Georges Lemaître, Arno Penzias, and Robert Wilson contributed to the big-bang model
Learn how astronauts exercise to combat the effects of microgravity on their bone and muscle masses
Learn how astronauts exercise to combat the effects of microgravity on their bone and muscle masses
Learn how the Sun warms moist air near the ground and causes it to rise and condense on dust particles
Learn how the Sun warms moist air near the ground and causes it to rise and condense on dust particles
Learn about platypus venom and why studying it may reveal new ways to manage pain in humans
Learn about platypus venom and why studying it may reveal new ways to manage pain in humans
Learn about and witness the blowfish's puffing defensive behaviour
Learn about and witness the blowfish's puffing defensive behaviour
Compare the elephant's 95-week gestation period with the marsupial American opossum's 12-13-day gestation
Compare the elephant's 95-week gestation period with the marsupial American opossum's 12-13-day gestation
Examine how the theory of plate tectonics explains volcanic activity, earthquakes, and mountains
Examine how the theory of plate tectonics explains volcanic activity, earthquakes, and mountains
Learn how Austrian Catholic monk and botanist Gregor Mendel observed properties of heredity
Learn how Austrian Catholic monk and botanist Gregor Mendel observed properties of heredity
Study the migratory, predatory, and living habits of North American bald eagles
Study the migratory, predatory, and living habits of North American bald eagles
Learn how Johannes Kepler challenged the Copernican system of planetary motion
Learn how Johannes Kepler challenged the Copernican system of planetary motion
Study DNA's double helix structure to learn how the organic chemical determines an organism's traits
Study DNA's double helix structure to learn how the organic chemical determines an organism's traits
Dive into stomate transpiration of a Pegonia plant highlighting functions of guard cells and root hairs
Dive into stomate transpiration of a Pegonia plant highlighting functions of guard cells and root hairs
Learn how plants use osmosis, facilitated diffusion, and active transport to ingest water and mineral salts
Learn how plants use osmosis, facilitated diffusion, and active transport to ingest water and mineral salts
Discover how the Moon's equal periods of rotation and revolution affect its orientation toward Earth
Discover how the Moon's equal periods of rotation and revolution affect its orientation toward Earth
Learn how DNA thermal cycler employs polymerase chain reaction to copy DNA strands
Learn how DNA thermal cycler employs polymerase chain reaction to copy DNA strands
Explore Uranus's nightside and ring system in this computer animation of the Voyager 2 space probe passing the planet on its way out of the solar system
Explore Uranus's nightside and ring system in this computer animation of the Voyager 2 space probe passing the planet on its way out of the solar system
Learn about the successes and failures of the U.S. space shuttle program and the cost of space exploration
Learn about the successes and failures of the U.S. space shuttle program and the cost of space exploration
Observe a quill-bearing North American rodent ambling and eating in its natural habitat
Observe a quill-bearing North American rodent ambling and eating in its natural habitat
See how parasitic plants form vascular unions with hosts to compensate for an inability to photosynthesize
See how parasitic plants form vascular unions with hosts to compensate for an inability to photosynthesize
Diagram stars, planets, constellations, and other heavenly bodies by understanding Earth's celestial sphere
Diagram stars, planets, constellations, and other heavenly bodies by understanding Earth's celestial sphere
Examine the preparation measures taken by foraging pikas and hibernating ground squirrels
Examine the preparation measures taken by foraging pikas and hibernating ground squirrels
See how sea creatures have evolved different adaptations to both catch prey and avoid becoming prey
See how sea creatures have evolved different adaptations to both catch prey and avoid becoming prey
Study the interdependence of a cell's nucleus, ribosomes, endoplasmic reticulum, and Golgi apparatus
Study the interdependence of a cell's nucleus, ribosomes, endoplasmic reticulum, and Golgi apparatus
Observe a predatory lion pride in a typical day of grooming, playing, hunting and eating prey, and sleeping
Observe a predatory lion pride in a typical day of grooming, playing, hunting and eating prey, and sleeping
Follow the electrical and chemical changes undergone to transmit an impulse through the human nervous system
Follow the electrical and chemical changes undergone to transmit an impulse through the human nervous system
Discover penguin habitats from the Galapagos Islands near the Equator to Antarctica
Discover penguin habitats from the Galapagos Islands near the Equator to Antarctica
Watch a desert thunderstorm and resulting flash flood scour the sandy soil and terrain
Watch a desert thunderstorm and resulting flash flood scour the sandy soil and terrain
Discover how Galapagos finches underwent adaptive radiation and aided Darwin in his theory of evolution
Discover how Galapagos finches underwent adaptive radiation and aided Darwin in his theory of evolution
Watch a tornado form during a strong thunderstorm
Watch a tornado form during a strong thunderstorm
Watch the courtship display of the male Anna's hummingbird and the hen's use of food to coax fledglings to fly
Watch the courtship display of the male Anna's hummingbird and the hen's use of food to coax fledglings to fly
Learn about the bacteria of the human body and examine the role of sweat glands in the immune system
Learn about the bacteria of the human body and examine the role of sweat glands in the immune system
Discover the differences between Louis Dollo's former reconstruction and David Norman's current reconstruction of Iguanodon
Discover the differences between Louis Dollo's former reconstruction and David Norman's current reconstruction of Iguanodon
Watch a North American raccoon sift for aquatic prey, using its keen sense of touch
Watch a North American raccoon sift for aquatic prey, using its keen sense of touch
Zoom in on the serpentine locomotion of the limbless, amphibious caecilian over soil
Zoom in on the serpentine locomotion of the limbless, amphibious caecilian over soil
Study the Permian Period's carnivorous Dimetrodon and its sail's role in thermoregulation
Study the Permian Period's carnivorous Dimetrodon and its sail's role in thermoregulation
Watch how a tire-swing pendulum demonstrates the law of conservation of energy
Watch how a tire-swing pendulum demonstrates the law of conservation of energy
Observe diatoms, microscopic sea organisms encased in silicified cell walls with intricate designs
Observe diatoms, microscopic sea organisms encased in silicified cell walls with intricate designs
Discover how hat-thrower fungi species fling sporangia to be consumed by grazing cows and horses
Discover how hat-thrower fungi species fling sporangia to be consumed by grazing cows and horses
Investigate how high radiant heat loss causes water vapor to condense into dew droplets
Investigate how high radiant heat loss causes water vapor to condense into dew droplets
Explore heat transfer and know the difference between heat and temperature
Explore heat transfer and know the difference between heat and temperature
Examine evolved differences between Galapagos tortoises across Galapagos Islands
Examine evolved differences between Galapagos tortoises across Galapagos Islands
Examine the structures adenine, ribose, and a three-phosphate chain in adenosine triphosphate molecule and their role in releasing energy for cellular activities
Examine the structures adenine, ribose, and a three-phosphate chain in adenosine triphosphate molecule and their role in releasing energy for cellular activities
See why the red panda is classified as the only member of the Ailuridae family
See why the red panda is classified as the only member of the Ailuridae family
Discover how genetic material is exchanged between bacteria via conjugation and transduction
Discover how genetic material is exchanged between bacteria via conjugation and transduction
Know how the World Meteorological Organization decides the names for hurricanes and typhoons
Know how the World Meteorological Organization decides the names for hurricanes and typhoons
Follow water in its many forms, from glaciers and clouds to freshwater rivers and saltwater oceans
Follow water in its many forms, from glaciers and clouds to freshwater rivers and saltwater oceans
See how water transforms between liquid, ice, and vapour in the water cycle
See how water transforms between liquid, ice, and vapour in the water cycle
Learn what makes a bison different from a buffalo
Learn what makes a bison different from a buffalo
Discover why some volcanic eruptions are more explosive, like at Mount Pinatubo in contrast to Kilauea
Discover why some volcanic eruptions are more explosive, like at Mount Pinatubo in contrast to Kilauea
Examine how a leopard frog's protruding independent eyes help it catch flies, earthworms, and other prey
Examine how a leopard frog's protruding independent eyes help it catch flies, earthworms, and other prey
Compare differences in the leaf structures and environments of flowering dicots, ferns, pine trees, and cacti
Compare differences in the leaf structures and environments of flowering dicots, ferns, pine trees, and cacti
Study how red blood cells transport oxygen and carbon dioxide through the human cardiovascular system
Study how red blood cells transport oxygen and carbon dioxide through the human cardiovascular system
Discover how bacteria evolved to survive in Earth's most extreme habitats, such as seafloor volcanic vents
Discover how bacteria evolved to survive in Earth's most extreme habitats, such as seafloor volcanic vents
Observe time-lapse photography of Penicillium mold releasing penicillin to its surroundings
Observe time-lapse photography of Penicillium mold releasing penicillin to its surroundings
Follow an amphibian's life cycle from an underwater egg to a land-roving organism
Follow an amphibian's life cycle from an underwater egg to a land-roving organism
Consider how Heinrich Hertz's discovery of the photoelectric effect led to Albert Einstein's theory of light
Consider how Heinrich Hertz's discovery of the photoelectric effect led to Albert Einstein's theory of light
Discern the difference between heat and temperature and review the three types of heat transfer
Discern the difference between heat and temperature and review the three types of heat transfer
Learn how mountains, bodies of water, and human habitation affect atmospheric activity
Learn how mountains, bodies of water, and human habitation affect atmospheric activity
Observe mountain lion cubs playing and being cared for and carried by their mother
Observe mountain lion cubs playing and being cared for and carried by their mother
Observe a female black pilot snake hatch a clutch of eggs and a newborn use its egg tooth to hatch
Observe a female black pilot snake hatch a clutch of eggs and a newborn use its egg tooth to hatch
Perceive refraction as a wave's speed is changed by its passing between different media
Perceive refraction as a wave's speed is changed by its passing between different media
Study the San Andreas Fault to see how horizontal movement displaces underlying rock and causes earthquakes
Study the San Andreas Fault to see how horizontal movement displaces underlying rock and causes earthquakes
Witness a combustion reaction between oxygen and cellulose to produce water, carbon dioxide, and carbon
Witness a combustion reaction between oxygen and cellulose to produce water, carbon dioxide, and carbon
Learn how termites use salivary secretions to cement debris to decaying wood nests in their rainforest habitat
Learn how termites use salivary secretions to cement debris to decaying wood nests in their rainforest habitat
Discern the difference between pahoehoe and aa volcanic lava flows at Kilauea, Hawaii
Discern the difference between pahoehoe and aa volcanic lava flows at Kilauea, Hawaii
Discover the ways to measure a forest and calculate the biomass of the organic material in a temperate forest
Discover the ways to measure a forest and calculate the biomass of the organic material in a temperate forest
Observe a kangaroo (a marsupial) carrying its joey and feeding and moving about in its natural habitat
Observe a kangaroo (a marsupial) carrying its joey and feeding and moving about in its natural habitat
Compare monocotyledons' embryonic endosperm to dicotyledons' prephotosynthesis food storage system
Compare monocotyledons' embryonic endosperm to dicotyledons' prephotosynthesis food storage system
Examine commensalism among fish species such as shrimp, the neon goby, and moray eels
Examine commensalism among fish species such as shrimp, the neon goby, and moray eels
See how Nicolaus Copernicus's heliocentric model replaced Aristotle's and Ptolemy's geocentric models
See how Nicolaus Copernicus's heliocentric model replaced Aristotle's and Ptolemy's geocentric models
Examine what happens to the electrons of two neutral objects rubbed together in a dry environment
Examine what happens to the electrons of two neutral objects rubbed together in a dry environment
Investigate vegetation unique to cloud forests atop tepui and lowland rainforests in Guiana Highlands region
Investigate vegetation unique to cloud forests atop tepui and lowland rainforests in Guiana Highlands region
Consider the theory of a large meteor or comet striking Earth and causing the extinction of dinosaurs
Consider the theory of a large meteor or comet striking Earth and causing the extinction of dinosaurs
Learn how Earth's crustal plates grind against each other and send energy waves in all directions
Learn how Earth's crustal plates grind against each other and send energy waves in all directions
Dissect the anatomy of icosahedral, rod-shaped, and bacteriophage virus structures in electron micrographs
Dissect the anatomy of icosahedral, rod-shaped, and bacteriophage virus structures in electron micrographs
Learn how tornadoes are formed and also how modern technologies help meteorologists track the moisture and pressure in the air for early signs of tornado formation
Learn how tornadoes are formed and also how modern technologies help meteorologists track the moisture and pressure in the air for early signs of tornado formation
Learn how satellites can be destroyed by space junk as small as a rogue screw
Learn how satellites can be destroyed by space junk as small as a rogue screw
Learn how pollution from industrial emissions and car exhaust is trapped against mountains to cause smog
Learn how pollution from industrial emissions and car exhaust is trapped against mountains to cause smog