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What the sources say

Common Pill BugArmadillidium vulgare

Every figure, record and mechanism on the Common Pill Bug profile was written from a source, and this is the working table behind it: 52 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Animal Diversity Web

Armadillidium vulgare. Animal Diversity Web.

The page saysrolls into a ball
The source saysArmadillidium vulgare exhibits a behavior of curling posterior joints in towards anterior joints in a sphere-like shape. This behavior, conglobationNote: tagline
The page saysA land-living crustacean
The source saysLike most other crustaceans, isopods have flattened plate-like uropodsNote: tagline; isopod = crustacean. Terrestrial: 'Habitat Regions terrestrial'
The page saysUnder stones and logs and in garden soil
The source saysCommon pillbugs can be found under pieces of natural debris such as stones or logs in forests, and in the soil of fields, gardens, or hedgerows.Note: stats.habitat
The page saysnative to the Mediterranean edge, now on nearly all landmasses
The source saysis native to the edge of the Mediterranean and has been introduced to nearly all worldwide terrestrial landmassesNote: stats.habitat
The page saysDecaying leaves, with some roots, fruit and seeds
The source saysA. vulgare breaks down the decaying leaf litter of many plant speciesNote: stats.diet
The page sayssome roots, fruit
The source sayscan also feed on small pieces of garden roots such as carrots, as well as fruitNote: stats.diet
The page saysCurls into a ball when squeezed or shaken
The source sayshas been observed in response to situations when the body is exposed directly to hard pressures or strong vibrations in the immediate areaNote: stats.superpower
The page saysit curls its rear body joints in toward its front ones into a sphere-like shape. The trick is called conglobation
The source sayscurling posterior joints in towards anterior joints in a sphere-like shape. This behavior, conglobation
The page saysa shield for the softer belly and legs, or a way to cut water loss
The source saysConglobation has been hypothesized to be either a defense mechanism used to shield the softer inner abdomen and limbs with the more stiff outer shell or an effective method of further preventing desiccation.
The page saysThe genus was once named Armadillo, after the armored mammal that does something similar
The source saysThe genus was once Armadillo , named after the similarly conglobating well-known armored mammal species.
The page saysbirds such as the common starling can beat it
The source saysThese defenses are inadequate against large predators, such as birds, including the Common Starling
The page saystropical ants of the genus Leptogenys have mandibles long enough to pry rolled-up pill bugs apart
The source saysA genus of tropical ants, Leptogenys sp., have elongated mandibles that allow them to pry apart conglobated individuals.
The page saysa pill bug is an isopod, a crustacean that lives on land
The source saysLike most other crustaceans, isopods have flattened plate-like uropodsNote: Order Isopoda per the classification table; terrestrial per Habitat Regions
The page saysA typical young adult is 10 millimetres long and 5 wide
The source saysTypical young adults are 10 mm long and 5 mm wide.
The page says0.060 to 0.116 grams
The source saysRange mass 0.060 to 0.116 g
The page saysin the usual molt cycle, for about two days after a molt the new shell is soft, and the animal cannot move or eat and is open to predators and drying out
The source saysThe molting cycle of males and non-reproducing females, called the normal intermolt, takes about 29 days. It begins with a 2 day period following the last molt, where the new, soft cuticle calicifies. The pillbug cannot move or eat, and is vulnerable to predation and dessication.
The page saysFemales carry their eggs in a fluid-filled pouch called a marsupium for two to three months
The source saysEggs are retained in the marsupium for two to three months until the mancas hatch.
The page saysfluid-filled pouch
The source saysthey are stored in the marsupium, a fluid-filled pouch present in reproducing females
The page saysa range of 6 to 300 young, averaging 100
The source saysRange number of offspring 6 to 300 Average number of offspring 100
The page saysIt moves slowly when the air is humid and faster when it is dry
The source saysindividuals move slowly during periods of high humidity and more rapidly during dry periods as they search for more humid areas
The page saysit is usually more active at night
The source saysthey are usually more active at night to further reduce desiccation risk
The page saysRoughly 13 metres a day in summer is its pace, falling to 6.6 in winter
The source saysIndividuals travel roughly twice as much during summer (13 meters per day) as winter (6.6 meters per day)
The page saysIt cannot swim
The source saysas they cannot swim
The page saysAt 20 to 30 degrees Celsius, pheromones (scent signals) draw pill bugs into clumps, which cuts the surface each one exposes to the heat
The source saysWhen air temperature ranges between 20°C to 30°C, pheromones activate causing conspecifics to be attracted to one another and bunch together in a group. This behavior helps decrease the surface area of any one individual in the group, and thereby exposure to the moisture-depleting external heat.
The page saysIt lives under stones and logs and in the soil of fields, gardens and hedgerows
The source saysCommon pillbugs can be found under pieces of natural debris such as stones or logs in forests, and in the soil of fields, gardens, or hedgerows.
The page saysMostly it eats decaying leaf litter
The source saysA. vulgare breaks down the decaying leaf litter of many plant species
The page sayssome data suggest almost ten percent of its diet is its own droppings, which recycles microbes and nutrients it missed the first time
The source saysSome data suggest that almost ten percent of the pill-bug's diet comes from self-coprophagy, which recirculates microbes and nutrients that were not fully processed during original digestion.
The page saysScientists suggest the shell shields the softer belly and legs, or that the ball helps the animal hold on to its body water
The source saysConglobation has been hypothesized to be either a defense mechanism used to shield the softer inner abdomen and limbs with the more stiff outer shell or an effective method of further preventing desiccation.Note: FAQ1
The page saysthe ball helps the animal hold on to its body water
The source saysan effective method of further preventing desiccationNote: FAQ1
The page saysaround 10 millimetres by 5 in a young adult
The source saysTypical young adults are 10 mm long and 5 mm wide.Note: FAQ2
The page saystravel about 13 metres a day in summer and 6.6 metres in winter
The source says(13 meters per day) as winter (6.6 meters per day)Note: FAQ3
The page saysNot Evaluated
The source saysIUCN Red List Not EvaluatedNote: stats.conservationStatus; GBIF/ITIS hold no Red List category for the name
The page saysit curls up when its body is pressed hard or the ground shakes nearby
The source sayshard pressures or strong vibrations in the immediate areaNote: FAQ1
The page saysPress hard on a common pill bug (*Armadillidium vulgare*) or shake the ground near it, and it curls its rear body joints in toward its front ones into a sphere-like shape
The source sayscurling posterior joints in towards anterior joints in a sphere-like shape. This behavior, conglobation, has been observed in response to situations when the body is exposed directly to hard pressures or strong vibrations
The page saysMuch of a pill bug's behaviour is a fight against drying out
The source saysMuch of the behavior of Armadillidium vulgare revolves around a constant struggle to preserve body moisture and prevent unnecessary desiccation.
The page saysThe species comes from the Mediterranean's edge and has been carried to nearly all landmasses
The source saysis native to the edge of the Mediterranean and has been introduced to nearly all worldwide terrestrial landmasses
The page saysand seeds
The source saysArmadillidium vulgare has also been known to be granivorous, although seeds are likely only eaten in absence of other, more desirable food sourcesNote: stats.diet
The page saysIts body is an oval about twice as long as it is wide
The source saysArmadillidium vulgare has an oval body shape approximately twice as long as it is wide.Note: FAQ2
The page saysPress hard on a pill bug or shake the ground near it, and it curls its body into a sphere-like ball
The source sayscurling posterior joints in towards anterior joints in a sphere-like shape. This behavior, conglobation, has been observed in response to situations when the body is exposed directly to hard pressures or strong vibrationsNote: vibe.reason

Source
02

Becker, Ziegler & Epple 2005

Becker, Ziegler & Epple (2005). The mineral phase in the cuticles of two species of Crustacea consists of magnesium calcite, amorphous calcium carbonate, and amorphous calcium phosphate. Dalton Transactions.

The page saysfound crystalline magnesium calcite plus two non-crystalline forms, calcium carbonate and calcium phosphate
The source saysthe cuticles consist of crystalline magnesium calcite, amorphous calcium carbonate (ACC), and amorphous calcium phosphate (ACP)
The page saysa study of the cuticles (outer shells) of two woodlice species, this one included
The source saysThe cuticules (shells) of the woodlice Porcellio scaber and Armadillidium vulgare were analysed

Source
03

Leclercq et al. 2016

Leclercq et al. (2016). Birth of a W sex chromosome by horizontal transfer of Wolbachia bacterial symbiont genome. Proceedings of the National Academy of Sciences.

The page saysin which bacterial DNA has become a new sex chromosome
The source saysWolbachia bacterial endosymbionts triggered the evolution of new sex chromosomes in the common pillbug Armadillidium vulgareNote: tagline
The page saysResearchers found a 3-megabase insert of a feminizing Wolbachia genome inside the pill bug's own nuclear genome
The source saysWe identified a 3-Mb insert of a feminizing Wolbachia genome that was recently transferred into the pillbug nuclear genome.Note: second half: Our results support the conclusion that the Wolbachia insert is now acting as a female sex-determining region in pillbugs
The page saysThe researchers concluded that the chromosome carrying the insert is a new W sex chromosome
The source saysthe chromosome carrying the insert is a new W sex chromosome
The page saysa 3-megabase stretch of its DNA had moved into the pill bug's own genome
The source saysWe identified a 3-Mb insert of a feminizing Wolbachia genome that was recently transferred into the pillbug nuclear genome.Note: FAQ4
The page saystheir results support it now acting as a female sex-determining region
The source saysOur results support the conclusion that the Wolbachia insert is now acting as a female sex-determining region in pillbugs
The page sayswhich would make a bacterium's DNA part of what decides whether a pill bug is female
The source saysbacteria-to-animal horizontal genome transfer represents a remarkable mechanism underpinning the birth of sex chromosomes
The page saysthe authors concluded that this stretch now works as a female sex-determining region
The source saysOur results support the conclusion that the Wolbachia insert is now acting as a female sex-determining region in pillbugsNote: FAQ4

Source
04

Cordaux et al. 2004

Cordaux et al. (2004). Evidence for a new feminizing Wolbachia strain in the isopod Armadillidium vulgare: evolutionary implications. Heredity.

The page saysWolbachia are bacteria that live inside cells and pass from mother to young
The source saysWolbachia are intracellular maternally inherited alpha-Proteobacteria infecting a wide range of arthropods.
The page saysIn this pill bug, at least two strains turn genetic males into females
The source saysInoculation experiments indicated that the new wVulM bacterial strain also induces feminization in A. vulgare.Note: the other is wVulC, 'the known Wolbachia strain is responsible for feminization of genetic males'
The page saysWolbachia is a bacterium that lives inside cells and passes from mothers to young
The source saysWolbachia are intracellular maternally inherited alpha-Proteobacteria infecting a wide range of arthropods.Note: FAQ4
The page saysin this species it turns genetic males into females
The source saysIn the common pill bug Armadillidium vulgare, the known Wolbachia strain is responsible for feminization of genetic males.Note: FAQ4

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.