Animalia Stupendium: The Coconut Crab
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Welcome to Stuff to Blow Your Mind, a production of iHeartRadio. Welcome to Animalia Stupendium. My name is Argo Mandonese, returned from accidental imprisonment within the magic mirror of Mool.

I am, as always, your tireless creature chronicler. But mere monsters, of course, hold no mystery for me these days. Dragons are drab, and even the specular fish in the mirror failed to rouse me during my imprisonment. And so once more, I turn my attention to the strange fauna of a land called Earth.

Travel with me, gentle reader, as we consider the mighty Coconut Crab. Common name, Coconut Crab. Scientific classification, Burgos Latero. Frequency and range, various islands of the Indian and Pacific Ocean. Size, up to 3 feet or 0.9 meters across. Diet, fruit, nuts, seed, and carrion. Treasure hoard, none. Challenge rating, 2.

Also known as the robber crab, the coconut crab resembles nothing so much as a gnarled, disembodied claw. It is not a true crab, but rather a giant terrestrial species of hermit crab. As adults, however, they outgrow their need for pilfered shells and instead develop a tough, leathery exoskeleton.

that provides ample protection on their scattered island habitats. They are the largest land-living arthropod on Earth. Nocturnal scavengers, the coconut crabs spend the daylight hours in their rocky burrows and then venture out in the dark to find morsels of fruit or nut, including their namesake, the coconut, which they can climb trees to obtain if need be.

Meat, however, is very much on the menu for these lumbering creatures, as they'll gladly tear into carrion should they chance across it. And shockingly, they may also even actively hunt living prey. Yes, biologists have in fact observed them sneak-attacking red-footed boobies in the night. No tree branch, it would seem, is safe from their hunger. Stealth roll!

Success! The coconut crab benefits from great strength, with specimens able to lift weights of 30 kilograms or 66 pounds.

And then there are the claws to consider, capable of closing with a force equal to 80 times the individual's own body mass, indeed making it more than capable of breaking into a coconut as well as into the soft bodies of various birds, boobies, swallows, or otherwise. Pinscher damage. The coconut crab is understood to be an evolutionary offshoot

of the various hermit crab species. This would have occurred some 2.6 to 5.3 million years ago, perhaps due to changes that robbed the robber crab here of its shelter options, forcing it to grow larger and tougher in order to thrive in a shell-free terrestrial environment.

Now to be sure, juvenile coconut crabs still make use of scavenged shells. And we must also note that while the adults live and die on land and can never truly return to the ocean, they still must release their eggs into the water in order to ensure the next generation of coconut crabs.

In the ocean, the hatched free-swimming shrimp-like larvae called zoia disperse, clinging to bits of vegetation, even coconut husks, for a period of several weeks, before becoming equally free-swimming and shrimp-like glaucothoei, which find suitable shells on the seabed.

Then they begin their march towards the various islands that will serve their fully terrestrial juvenile and adult form. An amazing journey. Humans never get to live as free-swimming larvae. I mean, except for us wizards in certain circumstances, of course.

There are more mysteries concerning the coconut crab to consider, but for now I must retire my wizard's quill and allow my familiars some respite. But I shall return with even more wonders of the natural world.

Hi, this is Robert Lamb. Thanks once more to the wizard Argo Madenese for joining us on the episode. Sources for it included Coconut Crabs, The Bird-Eating Behemoth Thriving on Isolated Tropical Islands by Emily Osterloff, Natural History Museum, The San Francisco Zoo, Ruler of the Etau, The World's Largest Land Invertebrate by Mark E. Lydra, Frontiers in Ecology and the Environment, 2017,

A Mighty Claw, Pinching Force of the Coconut Crab, the Largest Terrestrial Crustacean by Oka et al., PLOS 1, 2016. Pinching Simulation of the Coconut Crab, Considering the 3D Shape and Internal Characteristics of the Robust Claw Exoskeleton, Inoue et al., Results in Engineering, 2025.

Status of the Coconut Crab, Burgess Latreau in Niowei by Elagi et al., Pacific Community, 2015. And to a very limited extent, my own recent observations in Raja Ampat. Thanks as always to the excellent J.J. Possway for producing this episode. If you wish to contact Argo Mandonese with recommendations for future episodes, you can send an email to contact at stufftoblowyourmind.com.

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