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 (Tenrecinae) exhibit the ability to conglobate. [1] 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. [2]
Earthworms may volvate during periods of extreme heat or drought.
Among pill millipedes, volvation is both a protection against external threats and against dehydration. [3]
Woodlice or pillbugs (Armadillidae) curl themselves into "pills" not only for defense, but also to conserve moisture while resting or sleeping, because they must keep their pseudotrachaea ("gills") wet. Volvation is particularly well evolved in subterranean isopods, but only Caecosphaeroma burgundum is able to roll up into a hermetic sphere without any outward projections, and thus "approaches perfection in volvation". [4]
Multi-shelled chitons also volvate, although evidence suggests that they do not use this behavior as an anti-predatory defense but rather as a form of locomotion. [1]
In vertebrates, an animal's decision to volvate is mediated by the periaqueductal gray region. [5]
Armadillos are New World placental mammals in the order Cingulata. The Chlamyphoridae and Dasypodidae are the only surviving families in the order, which is part of the superorder Xenarthra, along with the anteaters and sloths. Nine extinct genera and 21 extant species of armadillo have been described, some of which are distinguished by the number of bands on their armor. All species are native to the Americas, where they inhabit a variety of different environments.
Xenarthra is a major clade of placental mammals native to the Americas. There are 31 living species: the anteaters, tree sloths, and armadillos. Extinct xenarthrans include the glyptodonts, pampatheres and ground sloths. Xenarthrans originated in South America during the late Paleocene about 60 million years ago. They evolved and diversified extensively in South America during the continent's long period of isolation in the early to mid Cenozoic Era. They spread to the Antilles by the early Miocene and, starting about 3 Mya, spread to Central and North America as part of the Great American Interchange. Nearly all of the formerly abundant megafaunal xenarthrans became extinct at the end of the Pleistocene.
The ball python, also called the royal python, is a python species native to West and Central Africa, where it lives in grasslands, shrublands and open forests. This nonvenomous constrictor is the smallest of the African pythons, growing to a maximum length of 182 cm (72 in). The name "ball python" refers to its tendency to curl into a ball when stressed or frightened.
Armadillidiidae is a family of woodlice, a terrestrial crustacean group in the order Isopoda. Unlike members of some other woodlice families, members of this family can roll into a ball, an ability they share with the outwardly similar but unrelated pill millipedes and other animals. This ability gives woodlice in this family their common names of pill bugs or roly polies. Other common names include slaters,potato bugs, doodle bugs and cheeselogs. Most species are native to the Mediterranean Basin, while a few species have wider European distributions. The best-known species, Armadillidium vulgare, was introduced to New England in the early 19th century and has become widespread throughout North America.
A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of locomotion. Burrows provide a form of shelter against predation and exposure to the elements, and can be found in nearly every biome and among various biological interactions. Many animal species are known to form burrows. These species range from small invertebrates, such as the Corophium arenarium, to very large vertebrate species such as the polar bear. Burrows can be constructed into a wide variety of substrates and can range in complexity from a simple tube a few centimeters long to a complex network of interconnecting tunnels and chambers hundreds or thousands of meters in total length; an example of the latter level of complexity, a well-developed burrow, would be a rabbit warren.
The long-eared hedgehog is a species of hedgehog native to Central Asian countries and some countries of the Middle East. The long-eared hedgehog lives in burrows that it either makes or finds and is distinguished by its long ears. It is considered one of the smallest Middle Eastern hedgehogs. This hedgehog is insectivorous but may also feed on small vertebrates and plants. In captivity they can live for over 7 years.
The Indian hedgehog is a species of hedgehog native to India and Pakistan. It mainly lives in sandy desert areas but can be found in other environments.
The nine-banded armadillo, also known as the nine-banded long-nosed armadillo or common long-nosed armadillo, is a mammal found in North, Central, and South America, making it the most widespread of the armadillos. Its ancestors originated in South America, and remained there until the formation of the Isthmus of Panama allowed them to enter North America as part of the Great American Interchange. The nine-banded armadillo is a solitary, mainly nocturnal animal, found in many kinds of habitats, from mature and secondary rainforests to grassland and dry scrub. It is an insectivore, feeding chiefly on ants, termites, and other small invertebrates. The armadillo can jump 3–4 ft (91–122 cm) straight in the air if sufficiently frightened, making it a particular danger on roads. It is the state small mammal of Texas.
The Brazilian three-banded armadillo is an armadillo species endemic to eastern Brazil, where it is known as tatu-bola. It is one of only two species of armadillo that can roll into a ball. It has suffered a 30% decline in population in the last 10 years.
Terrestrial locomotion has evolved as animals adapted from aquatic to terrestrial environments. Locomotion on land raises different problems than that in water, with reduced friction being replaced by the increased effects of gravity.
Armour or armor in animals is external or superficial protection against attack by predators, formed as part of the body, usually through the hardening of body tissues, outgrowths or secretions. It has therefore mostly developed in 'prey' species.
The wildlife of the Democratic Republic of the Congo includes its flora and fauna, comprising a large biodiversity in rainforests, seasonally flooded forests and grasslands.
Glomeris marginata is a common European species of pill millipede. It is a short millipede, rounded in cross-section, which is capable of rolling itself up into a ball ("volvation") when disturbed. This behaviour is also found in the pill woodlouse Armadillidium, with which G. marginata is often confused.
Glomerida is an order of pill-millipedes found primarily in the Northern Hemisphere. They superficially resemble pill-bugs or woodlice, and can enroll into a protective ball. They have twelve body segments, 17 to 19 pairs of legs, and males have enlarged rear legs involved in mating. The order includes about 30 genera and at least 280 species, including Glomeris marginata, the common European pill-millipede. The order contains members in Europe, South-east Asia and the Americas from California to Guatemala. Although historically considered closely related with the similar sphaerotheriidans that also enroll, some DNA evidence suggest they may be more closely related to glomeridesmidans, a poorly known order that does not enroll.
A woodlouse is any crustacean belonging to the suborder Oniscidea within the order Isopoda. They get their name from often being found in old wood.
Sphaerotheriida is an order of millipedes in the infraclass Pentazonia, sometimes known as giant pill millipedes. They inhabit Southern Africa, Madagascar, South and Southeast Asia, Australia and New Zealand. Like the Northern Hemisphere pill millipedes of the order Glomerida, these millipedes can roll into a ball when disturbed. When they are rolled-up, most sphaerotheriidans reach a maximum size of a cherry or golf ball, but some species from Madagascar can even reach the size of an orange. When rolled-up, predators are unable to unravel giant pill millipedes since the margins of their second and last dorsal plates fit perfectly into one another, creating a sealed ball. A few giant pill millipede species are able to produce sound, the only millipedes known to do this. This order of millipedes is also unique in that some African species are used for medicinal purposes.
The Zoo In Forest Park and Education Center is a nonprofit zoo situated in Forest Park located in Springfield, Massachusetts. It spans over an area of four acres and is home to a variety of exotic, native, and endangered species.
The pangolin trade is the illegal poaching, trafficking, and sale of pangolins, parts of pangolins, or pangolin-derived products on the black market. Pangolins are believed to be the world's most trafficked mammal, accounting for as much as 20% of all illegal wildlife trade. According to the International Union for Conservation of Nature (IUCN), more than a million pangolins were poached in the decade prior to 2014.
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 ; they are white in Monolistra but bluish-green in Caecosphaeroma. C. burgundum is the most studied species.
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: CS1 maint: location (link)....the affective region called the periaqueductal gray signals the motor panic actions of fleeting, curling one's body into a ball for protection, sweating, and so on.