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Tardigrade

Tardigrade
Tardigrades (also known as waterbears or moss piglets)[2][3][4] are water-dwelling, segmented micro-animals, with eight legs.[2] They were first described by the German pastor Johann August Ephraim Goeze in 1773. The name Tardigrada (meaning "slow stepper") was given three years later by the Italian biologist Lazzaro Spallanzani.[5] Since 1778, over 1,150 tardigrade species have been identified. Tardigrades are classified as extremophiles, organisms that can thrive in a physically or geochemically extreme condition that would be detrimental to most life on Earth.[6][7][3] For example, tardigrades can withstand temperatures from just above absolute zero to well above the boiling point of water, pressures about six times greater than those found in the deepest ocean trenches, ionizing radiation at doses hundreds of times higher than the lethal dose for a human, and the vacuum of outer space. Tardigrades form the phylum Tardigrada, part of the superphylum Ecdysozoa. Description[edit] Related:  Space

Cuttlefish Cuttlefish eat small mollusks, crabs, shrimp, fish, octopuses, worms, and other cuttlefish. Their predators include dolphins, sharks, fish, seals, seabirds, and other cuttlefish. Their life expectancy is about one to two years. Recent studies indicate cuttlefish are among the most intelligent invertebrates.[2] Cuttlefish also have one of the largest brain-to-body size ratios of all invertebrates.[2] Video of a cuttlefish in its natural habitat Physiology[edit] Cuttlebone[edit] A cuttlefish possesses an internal structure called the cuttlebone, which is porous and is made of aragonite. This broadclub cuttlefish (Sepia latimanus) can go from camouflage tans and browns (top) to yellow with dark highlights (bottom) in less than a second. Skin[edit] An infant cuttlefish protects itself with camouflage The chromatophores are elastic sacs containing different pigments. Camouflage[edit] The color variations in the mimicked substrate and animal skin are very similar. Eyes[edit] Cuttlefish eye closeup

Cmdr_Hadfield : Tonight's Finale: Our Earth... Micro-animal Micro-animals are animals that are microscopic and thus cannot be seen with the naked eye and can only be observed under a microscope. Mostly these microorganisms are multicellular but none are vertebrates. Microscopic arthropods include dust mites, spider mites, and some crustaceans such as copepods and the cladocera. Another common group of microscopic animals are the rotifers, which are filter feeders that are usually found in fresh water. Turritopsis nutricula Turritopsis nutricula is a small jellyfish. Several different species of the genus Turritopsis were formerly classified as T. nutricula, including the "immortal jellyfish" which is now classified as T. dohrnii.[2] References[edit] External links[edit] Media related to Turritopsis at Wikimedia Commons Data related to Turritopsis nutricula at Wikispecies

Astronomy Picture of the Day The NeverEnding Story (film) The book describes the fantasy world of Fantasia which is being threatened by a force called "The Nothing," a void of darkness that consumes everything. The Childlike Empress (Tami Stronach), who rules over Fantasia from the Ivory Tower, has fallen ill due to the Nothing, and she has summoned Atreyu (Noah Hathaway), a young warrior from the Plains People, to discover the means to end the Nothing. Atreyu is given AURYN, a medallion to protect and guide him. As Atreyu sets out, the Nothing summons Gmork (voiced by Alan Oppenheimer), a vicious, but highly intelligent werewolf, to kill Atreyu. Atreyu's quest directs him to an ancient being called Morla that resides in the Swamps of Sadness. Atreyu attempts to trek through the Swamps but even AURYN cannot protect him indefinitely. The two try to locate the boundary of Fantasia, but the power of the Nothing has grown, and Atreyu is knocked from Falkor's back into the Sea of Possibilities, losing AURYN in the process. Notes

Alpheidae The family is diverse and worldwide in distribution, consisting of about 600 species within 38 or more genera.[1] The two most prominent genera are Alpheus and Synalpheus, with species numbering well over 250 and 100, respectively.[2][3] Most snapping shrimp dig burrows and are common inhabitants of coral reefs, submerged seagrass flats and oyster reefs. While most genera and species are found in tropical and temperate coastal and marine waters, Betaeus inhabits cold seas and Potamalpheops is found only in freshwater caves. When in colonies, the snapping shrimp can interfere with sonar and underwater communication.[4][5][6] The shrimp are a major source of noise in the ocean.[4] Description[edit] Ecology[edit] Some pistol shrimp species share burrows with goby fishes in a symbiotic relationship. Social behavior has been discovered in the genus Synalpheus. Pistol shrimp have also been noted for their ability to reverse claws. Snapping effect[edit] General[edit] References[edit]

Astrophysics: Fire in the hole! Andy Potts In March 2012, Joseph Polchinski began to contemplate suicide — at least in mathematical form. A string theorist at the Kavli Institute for Theoretical Physics in Santa Barbara, California, Polchinski was pondering what would happen to an astronaut who dived into a black hole. Obviously, he would die. But how? According to the then-accepted account, he wouldn’t feel anything special at first, even when his fall took him through the black hole’s event horizon: the invisible boundary beyond which nothing can escape. But Polchinski’s calculations, carried out with two of his students — Ahmed Almheiri and James Sully — and fellow string theorist Donald Marolf at the University of California, Santa Barbara (UCSB), were telling a different story1. Free interview Zeeya Merali talks about what would happen if she fell into a black hole The team’s verdict, published in July 2012, shocked the physics community. Fiery origins Quantum mechanics says that information cannot be destroyed.

1:Face Charity Watch | Changing the world 1:Face at a time Mantis shrimp Called "sea locusts" by ancient Assyrians, "prawn killers" in Australia and now sometimes referred to as "thumb splitters" – because of the animal's ability to inflict painful gashes if handled incautiously[4] – mantis shrimp sport powerful claws that they use to attack and kill prey by spearing, stunning, or dismemberment. Although it only happens rarely, some larger species of mantis shrimp are capable of breaking through aquarium glass with a single strike from this weapon.[5] Ecology[edit] These aggressive and typically solitary sea creatures spend most of their time hiding in rock formations or burrowing intricate passageways in the sea bed. Classification and the claw[edit] Mantis shrimp from the front Around 400 species of mantis shrimp have currently been described worldwide; all living species are in the suborder Unipeltata.[6] They are commonly separated into two distinct groups determined by the manner of claws they possess: Eyes[edit] Suggested advantages of visual system[edit]

witter / AAVSO : #AAVSO SN2012am in M65: Here ...

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