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What the sources say

Coconut CrabBirgus latro

Every figure, record and mechanism on the Coconut Crab profile was written from a source, and this is the working table behind it: 56 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, University of Michigan

Birgus latro (coconut crab). Animal Diversity Web, University of Michigan.

The page sayscoconut-cracking claws
The source saysIndividuals have also been observed using their claws to poke the coconut in a soft spot (through one of the “eyes”), splitting it open.
The page saysa leg span of up to a meter
The source saysup to 1 m from leg tip to leg tip
The page saysCoastal habitats and burrows on tropical Indian and Pacific Ocean islands, up to 6 km from the shore
The source saysCoconut crabs are found in coastal habitats on marine islands, or small islets near larger, continental islands, as much as 6 km from shore. They create burrows in the substrateNote: "up to" restates "as much as"
The page saysCoconut flesh and other tropical fruit
The source saystropical fruits (such as Pandanus fruits ... and coconut meat
The page sayscarrion, including other crabs
The source sayshave been observed feeding on carrion (including other crustaceans such as red crabs (Gecarcoidea natalis))
The page saysis a hermit crab that outgrows the borrowed shells of its youth
The source saysCoconut crabs are hermit crabs, and juveniles use mollusk shells for protection until they grow too large for available shells.
The page saysAnimal Diversity Web records a maximum carapace length of 200 millimeters, a leg span of up to a meter from tip to tip, and a top weight of 4 kilograms
The source saysa maximum carapace length of 200 mm (up to 1 m from leg tip to leg tip) and a maximum weight of 4 kg
The page saysA crab has several ways into a coconut
The source saysThese crabs use a variety of methods to obtain meat from a coconut.
The page saysit may haul one up a tree and drop it
The source saysA crab may carry the coconut up a tree and then drop it, cracking it open by the force of its impact on the ground.
The page saysor poke a claw through one of the coconut's soft "eyes" to split it open
The source saysIndividuals have also been observed using their claws to poke the coconut in a soft spot (through one of the “eyes”), splitting it open.
The page saysBreeding still needs the sea
The source saysAdult coconut crabs are primarily terrestrial; eggs are released into the sea, where larval development occurs.
The page saysa female releases up to 138,000 eggs into shallow water in one spawn
The source saysa gravid female moves from land to shallow intertidal water and releases her eggs by shaking them into the water ... Females produce 50,000-138,000 embryos per spawn
The page saysthe hatchlings drift through several larval stages at sea before migrating onto land
The source saysLarvae undergo four or five zoeal stages ... This larval period is followed by a glaucothoe (amphibious) stage ... before migrating onto landNote: "drift" is ADW's "As planktonic larvae" (Food Habits section); the source's "typically" qualifies a shell-carrying detail this sentence omits, not the move onto land
The page sayscoconut crabs live in burrows
The source saysThey create burrows in the substrate, which provide protection and allow for food storage.
The page saysand are mostly solitary
The source saysIndividuals are primarily solitary, venturing out of their burrows only to forage or mate.
The page saysand carrion, other crabs included
The source saysAdults are omnivorous scavengers and have been observed feeding on carrion (including other crustaceans such as red crabs (Gecarcoidea natalis))
The page saysLarge adults can have a carapace up to 200 millimeters long, a leg span up to a meter tip to tip, and a weight up to 4 kilograms
The source saysa maximum carapace length of 200 mm (up to 1 m from leg tip to leg tip) and a maximum weight of 4 kg

Source
02

Oka, Tomita & Miyamoto 2016

Oka, Tomita & Miyamoto (2016). A Mighty Claw: Pinching Force of the Coconut Crab, the Largest Terrestrial Crustacean. PLOS ONE.

The page saysLand arthropod of up to 4 kilograms
The source saysthe reported maximum BW of the coconut crab is 4 kg
The page saysAn estimated 3,300-newton claw pinch for a 4-kilogram crab, calculated from measurements on wild animals
The source sayswe measured the pinching force of the chelae in 29 wild coconut crabs ... Based on the correlation between pinching force and body weight, the force potentially exerted by the largest crab (4 kg weight) reported in a previous study would be 3300 N
The page saysenough to beat the bite force of most living land predators, alligators excepted
The source saysthe pinching force of the coconut crab of 4 kg BW was estimated to be 3300 N. This force greatly exceeds that in all other crustacean species that have been reported [ 1 , 2 ], as well as the bite force for the majority of modern terrestrial predators, other than alligatorsNote: "most" is the source's "majority"; "living" its "modern"; "alligators excepted" its "other than alligators"
The page saysThe Mighty Claw
The source saysThe mighty claw is a terrestrial adaptationNote: heading; the paper's own phrase
The page saysThat claw is a serious tool.
The source saysThe mighty claw is a terrestrial adaptation that is not only a weapon, which can be used to prevent predator attack and inhibit competitors, but is also a toolNote: "serious" restates "mighty"
The page saysResearchers had 29 wild crabs, weighing up to 2.1 kilograms, pinch a steel sensor
The source sayswe measured the pinching force of the chelae in 29 wild coconut crabs (33–2,120 g in body weight) ... exerted by the crab while pinching a stainless steel stick-shaped sensorNote: 2.1 kg converted from 2,120 g
The page saysand the strongest pinch measured 1,765 newtons
The source saysThe maximum force ranged from 29.4 to 1,765.2 NNote: 1,765 rounded from 1,765.2 N; the strongest is the top of the range of each crab's maximum force
The page saysUsing their equation linking weight to pinch strength, the team estimated what a crab at the species' reported 4-kilogram maximum could manage: 3,300 newtons.
The source saysthe reported maximum BW of the coconut crab is 4 kg [ 12 ]. Applying our allometric scaling equation, the pinching force of the coconut crab of 4 kg BW was estimated to be 3300 N
The page saysThat estimated 3,300-newton pinch would far exceed the pinch of every other crustacean species reported
The source saysthe pinching force of the coconut crab of 4 kg BW was estimated to be 3300 N. This force greatly exceeds that in all other crustacean species that have been reported
The page saysand beat the bite force of most living land predators, alligators excepted.
The source saysThis force greatly exceeds that in all other crustacean species that have been reported [ 1 , 2 ], as well as the bite force for the majority of modern terrestrial predators, other than alligatorsNote: "most" is "majority"; "living" is "modern"
The page saysScientists measured the claw pinch of 29 wild coconut crabs weighing up to 2.1 kilograms; the strongest measured pinch hit 1,765 newtons.
The source sayswe measured the pinching force of the chelae in 29 wild coconut crabs (33–2,120 g in body weight). The maximum force ranged from 29.4 to 1,765.2 NNote: 2.1 kg converted from 2,120 g; 1,765 rounded from 1,765.2 N; the strongest is the top of the range of each crab's maximum force
The page saysPlugging the species' reported maximum weight of 4 kilograms into the team's equation linking weight to pinch strength gives an estimated 3,300 newtons
The source saysthe reported maximum BW of the coconut crab is 4 kg [ 12 ]. Applying our allometric scaling equation, the pinching force of the coconut crab of 4 kg BW was estimated to be 3300 N
The page sayswhich would beat the bite force of most living land predators, alligators excepted.
The source saysthe bite force for the majority of modern terrestrial predators, other than alligatorsNote: "most" is "majority"; "living" is "modern"
The page sayswhose strongest measured pinch hit 1,765 newtons
The source saysThe maximum force ranged from 29.4 to 1,765.2 NNote: 1,765 rounded from 1,765.2 N; the strongest is the top of the range of each crab's maximum force

Source
03

Kumaralingam 2020

Kumaralingam (2020). The Robber Crab Birgus latro (Linnaeus, 1767). Crustacea.

The page saysnuts, seeds
The source saysAdult coconut crabs feed on fruits, nuts, seeds
The page saysGrowing that big takes decades: a review of the species says it "reach[es] their maximum size only after 40-60 years,"
The source saysThey reach their maximum size only after 40-60 years.Note: [es] added for grammar
The page saysAdults scavenge fruit, nuts, seeds
The source saysAdult coconut crabs feed on fruits, nuts, seedsNote: "scavenge" is ADW's "omnivorous scavengers"
The page saysThey are also slow growers: a coconut crab does not reach its maximum size until it is 40 to 60 years old
The source saysThey reach their maximum size only after 40-60 years.Note: "not until" restates "only after"

Source
04

Stensmyr et al. 2005

Stensmyr et al. (2005). Insect-Like Olfactory Adaptations in the Terrestrial Giant Robber Crab. Current Biology.

The page saysOne study on the species puts the risk plainly: apart from its marine larval stage, the crab "is fully terrestrial, and will actually drown if submerged in water."
The source saysApart from the marine larval stage, this crab is fully terrestrial, and will actually drown if submerged in water
The page saysLungs on Land, Larvae at Sea
The source saysApart from the marine larval stage, this crab is fully terrestrialNote: heading; the lungs are the section's Greenaway claim
The page saysA Loner With a Nose Like an Insect's
The source saysThe insect nose of the robber crabNote: heading; "loner" is the section's ADW "primarily solitary" claim
The page saysOne study found the crab's nose has evolved to resemble an insect's, with similarities in physiology, behavior, and anatomy
The source saysthe robber crab has evolved an olfactory sense with a high degree of resemblance to the insect system. The similarities extend to physiological, behavioral, and morphological characters.
The page saysconvergent evolution, where similar pressures produce similar solutions
The source saysstriking example of convergent evolution and nicely illustrates how similar selection pressures result in similar adaptation
The page saysNot as an adult.
The source saysApart from the marine larval stage, this crab is fully terrestrial, and will actually drown if submerged in water
The page saysOne study puts it plainly: apart from its marine larval stage, the crab "is fully terrestrial, and will actually drown if submerged in water."
The source saysApart from the marine larval stage, this crab is fully terrestrial, and will actually drown if submerged in water

Source
05

Krieger et al. 2012

Krieger et al. (2012). Giant Robber Crabs Monitored from Space: GPS-Based Telemetric Studies on Christmas Island (Indian Ocean). PLoS ONE.

The page saysThe Biggest Arthropod on Land
The source saysthe world's largest land-living arthropodNote: heading; the body quotes the same line
The page saysa GPS-tracking study on Christmas Island calls it "the world's largest land-living arthropod."
The source saysWe investigated the navigational capabilities of the world's largest land-living arthropod
The page saysand the tracking study notes it "can reach an age of up to 60 years."
The source saysthis crab reaches 4 kg in weight and can reach an age of up to 60 years
The page saysSpread across small tropical islands in the Indian and Pacific Oceans
The source saysPopulations are distributed over small Indo-Pacific islands of the tropics
The page saysOn Christmas Island, GPS-tagged males made short trips from a home site, mostly at night
The source saysundertook short-distance excursions mostly at nightNote: every tagged crab was male: "we equipped 55 male robber crabs with GPS tags" (abstract)
The page saysand some roamed several kilometers between the coast and inland forest
The source saysBesides site fidelity with short-distance excursions, our data reveal long-distance movements (several kilometers) between the coast and the inland rainforest
The page sayscrabs moved away from home could find their way back over large distances
The source saystranslocation experiments show that robber crabs are capable of homing over large distances
The page saysmaking them the largest terrestrial arthropods known
The source saysthe world's largest land-living arthropodNote: ADW says the same ("the largest terrestrial arthropods known"); cited to the 2012 paper so the record does not rest on ADW
The page saysand can live up to 60 years
The source saysthis crab reaches 4 kg in weight and can reach an age of up to 60 years
The page sayswhose tracked males roamed several kilometers between coast and forest
The source saysBesides site fidelity with short-distance excursions, our data reveal long-distance movements (several kilometers) between the coast and the inland rainforest

Source
06

Greenaway 2003

Greenaway (2003). Terrestrial adaptations in the Anomura (Crustacea: Decapoda). Memoirs of Museum Victoria.

The page saysA coconut crab's gill area, for its body weight, is the smallest measured in any land crab, and its gills do little to take up oxygen
The source saysBirgus latro has the smallest weight specific gill area measured for any terrestrial decapod ... and they play little role in oxygen uptakeNote: land crabs are a subset of the source's terrestrial decapods, so the narrower claim follows from it
The page saysit breathes through branchiostegal lungs instead
The source saysInstead, oxygen uptake by B. latro occurs across the large, evaginated, branchiostegal lungs
The page saysIts gills play little part in taking up oxygen; that happens in its branchiostegal lungs.
The source saysthey play little role in oxygen uptake (Greenaway et al., 1988). Instead, oxygen uptake by B. latro occurs across the large, evaginated, branchiostegal lungs

Source
07

Cumberlidge 2020

Cumberlidge (2020). Birgus latro. The IUCN Red List of Threatened Species 2020: e.T2811A126813586.

The page saysVulnerable
The source saysIUCN Red List category: Vulnerable (VU).

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.