
Crab Facts: Claws, Shells & Secret Behaviors
Crabs are crustaceans found on every continent with over 7,000 species. Discover why crabs walk sideways, trade shells, and grow claws stronger than jaws.

Ravens are highly intelligent birds that use tools, plan for the future, and remember human faces. Discover raven problem solving, cultural significance, and surprising abilities.
Ravens rank among the most intelligent animals on Earth with problem solving abilities rivaling great apes. These large black birds use tools, plan seventeen hours ahead, engage in complex social manipulation, and remember individual human faces for years.
They plan for the future, a skill once thought unique to humans and great apes. Most remarkably, ravens pass the mirror test, recognizing themselves in reflections. This self-awareness appears in only a handful of species including dolphins, elephants, and great apes.
Ravens craft and use tools with sophistication that astonishes researchers. They bend wire into hooks to retrieve food from narrow tubes, demonstrating understanding of cause and effect. Wild ravens use sticks to probe for insects similar to how chimpanzees use termite fishing sticks.
Ravens engage in complex social behaviors including cooperation, deception, and manipulation. When hiding food caches, ravens check whether other ravens are watching. If observed, they create fake caches to mislead potential thieves, then return later to move food to secure locations.
In Norse mythology, the god Odin kept two ravens named Huginn and Muninn representing thought and memory. These ravens flew across the world each day reporting news to Odin, making them symbols of knowledge and wisdom. Native American traditions feature Raven as a trickster and creator figure with Pacific Northwest tribes telling stories of Raven stealing the sun to bring light to the world.
Ravens possess over thirty distinct calls conveying different meanings plus the ability to mimic sounds from their environment. Captive ravens learn to say words and phrases though less clearly than parrots. Wild ravens mimic wolf howls and coyote calls, possibly to attract these predators to carcasses too tough for raven beaks to open.
People often confuse ravens with crows, but several key differences distinguish these corvid relatives. Ravens are significantly larger at twenty four inches long compared to crows at seventeen inches. Ravens weigh two to four pounds while crows weigh under one pound.
Ravens appear in mythology worldwide, from Norse gods to Native American creation stories.
Tower of London ravens have been protected since the 1600s based on superstition that Britain will fall if they leave.
Edgar Allan Poe's poem The Raven cemented the bird's association with darkness and mystery in Western culture.
Ancient Celtic warriors believed ravens carried souls of the dead and seeing them before battle predicted outcomes.
Pacific Northwest tribes tell stories of Raven stealing the sun to bring light to the world.
Studies proved ravens pass the mirror test, recognizing themselves in reflections like great apes and dolphins.
Research showed ravens plan up to 17 hours ahead, saving tools for future use.
Scientists documented ravens creating fake food caches to deceive watching competitors.
Studies revealed ravens remember human faces for at least five years and hold grudges.
Research demonstrated ravens can bend wire into hooks to retrieve food, showing cause and effect understanding.
Ravens symbolize wisdom, mystery, and prophecy across diverse world cultures.
The Tower of London maintains resident ravens based on centuries old superstition about British sovereignty.
Ravens appear as trickster figures in Indigenous North American mythology from Alaska to Mexico.
Modern research on raven intelligence has changed scientific understanding of non mammalian cognition.
Ravens in popular culture often represent intelligence, mystery, or connection to the supernatural.
Before modern cognitive research, ravens were seen as simple scavengers associated with death and battlefields. Science considered complex planning and self awareness impossible in birds, assuming only primates possessed such advanced cognition. Ravens' intelligence was dismissed as instinct rather than genuine thinking.
After decades of controlled experiments, scientists recognized ravens as among Earth's most intelligent animals. They plan for the future, use and create tools, deceive competitors, recognize themselves in mirrors, and remember faces for years. Raven research fundamentally changed scientific understanding of animal cognition and proved complex intelligence evolved independently in birds.
Ravens plan up to 17 hours ahead, saving tools they will need later even when not currently useful
They remember individual human faces for at least 5 years and hold grudges against people who wronged them
Ravens pass the mirror test, recognizing themselves in reflections like dolphins, elephants, and great apes
Wild ravens slide down snowy hills repeatedly for apparent fun, then walk back up to slide again
Ravens bend wire into hooks to solve puzzles, demonstrating understanding of cause and effect
In Norse mythology, Odin's ravens Huginn and Muninn represent thought and memory, flying worldwide to gather information
Raven intelligence research expands understanding of cognition beyond primates and mammals
Their problem solving abilities rival seven year old children in some tests
Ravens demonstrate that complex thinking evolved independently in birds and mammals
Understanding corvid intelligence informs artificial intelligence and machine learning research
Raven populations indicate ecosystem health in many wilderness regions
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Ravens hold grudges for years. They remember faces of people who wronged them and warn other ravens.
They play for fun. Ravens slide down snowy hills repeatedly just for entertainment.
Ravens pass the mirror test. They recognize themselves in reflections like dolphins and great apes.
They plan 17 hours ahead. Ravens save tools for future use, once thought impossible for birds.
Ravens deceive competitors. They create fake food caches to mislead watching rivals.
They mimic wolf howls. Wild ravens call predators to carcasses too tough for their beaks.
Ravens rank among the most intelligent animals with problem solving abilities matching 7 year old children and rivaling great apes. They use tools, plan up to 17 hours ahead, understand cause and effect, and pass the mirror self recognition test. Their brain to body ratio is among the highest in birds, enabling complex cognition.
This article is reviewed by the Pagefacts team.
Editorial Approach:
This article reveals ravens plan 17 hours ahead like humans, hold grudges against specific people for years, and play by sliding down snowy hills for apparent fun.
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