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Volvation
Volvation (from Latin ''volvere'' "roll", and the suffix ''-(a)tion''; sometimes called enrolment or conglobation), is a defensive behavior in certain animals, in which the animal rolls its own body into a ball, presenting only the hardest parts of its integument (the animal's "armor"), or its spines to predators. Among mammals, vertebrates like pangolins (Manidae) and hedgehogs (Erinaceidae) exhibit the ability to conglobate. Armadillos in the genus Tolypeutes (South American three-banded armadillos) are able to roll into a defensive ball; however the nine-banded armadillo and other species have too many plates.. Earthworms may volvate during periods of extreme heat or drought. Among pill millipedes, volvation is both a protection against external threats and against dehydration. At least eight families of flat-backed millipedes are known to practice true volvation, they are referred to as ''oniscoid'' (woodlouse-like). The pauropod family Sphaeropauropodidae has the ability ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Caecosphaeroma En Boule
''Caecosphaeroma'' is a troglodytic isopod genus in the family Sphaeromatidae found in caves of NE and SW France. The genus was split off from Monolistra by Adrien Dollfus in 1896; in both genera, the female carries about 10 fertilized eggs in its external marsupium (brood pouch); they are white in ''Monolistra'' but bluish-green in ''Caecosphaeroma''. ''C. burgundum'' is the most studied species. Description They measure from 2–20 mm long. As cave dwellers, they have lost their vision, but remain sensitive to light, which they shun. They are capable of volvation (rolling themselves into a ball) to protect themselves, rest, or sleep. During copulation the male and female embrace takes the form of two concentric spheres. Development Larva remain in the marsupium about 12 months, and the animals continue growing for several years, reaching a final length of 10–20 mm. Evolution The marine ancestors of ''Caecosphaeroma'' are believed to have migrated up the course o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Caecosphaeroma
''Caecosphaeroma'' is a troglodytic isopod genus in the family Sphaeromatidae found in caves of NE and SW France. The genus was split off from Monolistra by Adrien Dollfus in 1896; in both genera, the female carries about 10 fertilized eggs in its external marsupium (brood pouch); they are white in ''Monolistra'' but bluish-green in ''Caecosphaeroma''. ''C. burgundum'' is the most studied species. Description They measure from 2–20 mm long. As cave dwellers, they have lost their vision, but remain sensitive to light, which they shun. They are capable of volvation (rolling themselves into a ball) to protect themselves, rest, or sleep. During copulation the male and female embrace takes the form of two concentric spheres. Development Larva remain in the marsupium about 12 months, and the animals continue growing for several years, reaching a final length of 10–20 mm. Evolution The marine ancestors of ''Caecosphaeroma'' are believed to have migrated up the cour ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Short-beaked Echidna
The short-beaked echidna (''Tachyglossus aculeatus''), also called the short-nosed echidna, is one of four living species of echidna, and the only member of the genus ''Tachyglossus'', from Ancient Greek (), meaning "fast", and (), meaning "tongue". It is covered in fur and spines and has a distinctive snout and a specialised tongue, which it uses to catch its insect prey at a great speed. Like the other extant monotremes, the short-beaked echidna lays eggs; the monotremes are the only living group of mammals to do so. The short-beaked echidna has extremely strong front limbs and claws, which allow it to burrow quickly with great power. As it needs to be able to survive underground, it has a significant tolerance to high levels of carbon dioxide and low levels of oxygen. It has no weapons or fighting ability but deters predators by curling into a ball and protecting itself with its spines. It cannot sweat or deal well with heat, so it tends to avoid daytime activity in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Animals
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia (). With few exceptions, animals consume organic material, breathe oxygen, have myocytes and are able to move, can reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. Animals form a clade, meaning that they arose from a single common ancestor. Over 1.5 million living animal species have been described, of which around 1.05 million are insects, over 85,000 are molluscs, and around 65,000 are vertebrates. It has been estimated there are as many as 7.77 million animal species on Earth. Animal body lengths range from to . They have complex ecologies and interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology, and the study of animal behaviour is known as ethology. The animal kingdom is divided into five major clades, namely Porifera, Ctenophora, P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Flat-backed Millipede
Polydesmida (from the Greek language, Greek ''poly'' "many" and ''desmos'' "bond") is the largest order (biology), order of millipedes, with more than 5,000 species, including all the millipedes reported to produce hydrogen cyanide (HCN). This order is also the most diverse of the millipede orders in terms of Morphology (biology), morphology. Millipedes in this order are found in all regions of the world other than Antarctica. Description Members of the order Polydesmida are also known as flat-backed millipedes, because on most species, each body segment has wide lateral keels known as paranota. These keels are produced by the posterior half (metazonite) of each body ring behind the collum (millipedes), collum. Polydesmids have no eyes, and vary in length from 1.4 to 134 mm. Many of the larger species show bright coloration patterns which warn predators of their toxic secretions. Adults usually have 20 segments, counting the collum as the first ring and the telson as the last rin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Lesser Hedgehog Tenrec
The lesser hedgehog tenrec (''Echinops telfairi'') is a species of mammal in the family Tenrecidae. It is the only species in the genus ''Echinops'' and is named in honour of Charles Telfair. It is endemic to Madagascar. Its natural habitats are subtropical or tropical dry forests, shrubland, and shrubland and dry savanna. Description The lesser hedgehog tenrec is a small, stout-bodied animal visually similar to a hedgehog, hence the name. Their tails are short, their limbs and muzzles are of moderate length, and their ears are prominent. The entire dorsum is covered with sharp spines. Color is usually yellow buff; individuals range from near white to almost black. Head and body length is . Weight is about . Lesser hedgehog tenrecs (like all tenrecs) have a cloaca (common urogenital opening), like a bird or a reptile. Behavior This tenrec is terrestrial. It spends its daytime hours resting under a log, a pile of branches, leaves, straws or in a hollow tree, although trees ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Asiatic Lions
The Asiatic lion is a lion population of the subspecies ''Panthera leo leo''. Until the 19th century, it occurred in Saudi Arabia, eastern Turkey, Iran, Mesopotamia, and from east of the Indus River in Pakistan to the Bengal region and the Narmada River in Central India. Since the turn of the 20th century, its range has been restricted to Gir National Park and the surrounding areas in the Indian state of Gujarat. The first scientific description of the Asiatic lion was published in 1826 by the Austrian zoologist Johann N. Meyer, who named it ''Felis leo persicus''. The population has steadily increased since 2010. In 2015, the 14th Asiatic Lion Census was conducted over an area of about ; the lion population was estimated at 523 individuals, and in 2017 at 650 individuals. In 2020 the population was 674 and by 2025 it had increased to 891. Taxonomy ''Felis leo persicus'' was the scientific name proposed by Johann N. Meyer in 1826 who described an Asiatic lion skin from Persia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Indian Pangolin
The Indian pangolin (''Manis crassicaudata''), also called thick-tailed pangolin and scaly anteater, is a pangolin native to the Indian subcontinent. Like other pangolins, it has large, overlapping Scale (zoology), scales on its body which act as Armour (zoology), armour. The colour of its scales varies depending on the colour of the earth in its surroundings. It can also curl itself into a ball as self-defence against predators such as the tiger. It is an insectivore feeding on ants and termites, digging them out of mounds and logs using its long claws, which are as long as its fore limbs. It is nocturnal and rests in deep burrows during the day. It is not common anywhere in its range, and is threatened by hunting for its meat and various body parts used in traditional medicine. Characteristics The Indian pangolin is a solitary, shy, slow-moving, nocturnal mammal. It is about long from head to tail, the tail usually being long, and weighs . Females are generally smaller th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Southern Three-banded Armadillo
The southern three-banded armadillo , also known as La Plata three-banded armadillo or Azara's domed armadillo, is an armadillo species from South America. It is found in parts of northern Argentina, southwestern Brazil, Paraguay and Bolivia, at elevations from sea level to . The southern three-banded armadillo and the other member of the genus ''Tolypeutes'', the Brazilian three-banded armadillo, are the only species of armadillos capable of rolling into a complete ball to defend themselves. The three characteristic bands that cover the back of the animal allow it enough flexibility to fit its tail and head together, allowing it to protect its underbelly, limbs, eyes, nose and ears from predators. The shell covering its body is armored and the outer layer is made out of keratin, the same protein that builds human fingernails. They are typically a yellow or brownish color. They are among the smaller armadillos, with a head-and-body length of about and a weight between .Armadill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
European Hedgehog
The European hedgehog (''Erinaceus europaeus''), also known as the West European hedgehog or common hedgehog, is a hedgehog species native to Europe from Iberia and Italy northwards into Scandinavia and westwards into the British Isles.Harris, S. & Yalden, D.W. (2008). ''Mammals of the British Isles: Handbook, 4th Edition.'' The Mammal Society, Southampton. It is a generally common and widely distributed species that can survive across a wide range of habitat types. It is a well-known species, and a favourite in European gardens, both for its endearing appearance and its preference for eating a range of garden pests. While populations are currently stable across much of its range, it is declining severely in Great Britain where it is now Red Listed, meaning that it is considered to be at risk of local extinction. Outside its native range, the species was introduced to New Zealand during the late nineteenth and early twentieth centuries. Description The European hedgehog has a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Periaqueductal Gray
The periaqueductal gray (PAG), also known as the central gray, is a brain region that plays a critical role in autonomic function, motivated behavior and behavioural responses to threatening stimuli. PAG is also the primary control center for descending pain modulation. It has enkephalin-producing cells that suppress pain. The periaqueductal gray is the gray matter located around the cerebral aqueduct within the tegmentum of the midbrain. It projects to the nucleus raphe magnus, and also contains descending autonomic tracts. The ascending pain and temperature fibers of the spinothalamic tract send information to the PAG via the spinomesencephalic pathway (so-named because the fibers originate in the spine and terminate in the PAG, in the mesencephalon or midbrain). This region has been used as the target for brain-stimulating implants in patients with chronic pain. Role in analgesia Stimulation of the periaqueductal gray matter of the midbrain activates enkephalin-r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Chiton
Chitons () are marine molluscs of varying size in the class Polyplacophora ( ), formerly known as Amphineura. About 940 extant and 430 fossil species are recognized. They are also sometimes known as sea cradles or coat-of-mail shells or suck-rocks, or more formally as loricates, polyplacophorans, and occasionally as polyplacophores. Chitons have a shell composed of eight separate shell plates or valves. These plates overlap slightly at the front and back edges, and yet articulate well with one another. Because of this, the shell provides protection at the same time as permitting the chiton to flex upward when needed for locomotion over uneven surfaces, and even allows the animal to curl up into a ball when dislodged from rocks. The shell plates are encircled by a skirt known as a girdle. Habitat Chitons live worldwide, from cold waters through to the tropics. They live on hard surfaces, such as on or under rocks, or in rock crevices. Some species live quite high in the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
