
Crab Facts: Claws, Shells & Secret Behaviors
Crabs are crustaceans found on every continent with over 7,000 species. Discover why crabs walk sideways, trade shells, and grow claws stronger than jaws.

Wombats produce cube shaped poop and use their hard rumps as weapons. Discover wombat defenses, burrows, speed, and unique marsupial adaptations.
Wombats are stocky marsupials native only to Australia that build extensive underground burrow systems. Despite their cute, cuddly appearance, wombats are surprisingly fast, powerful, and capable of aggressive defense. They are most famous for being the only animal in the world that produces cube shaped poop, a biological mystery that fascinates scientists and the public alike.
Wombats produce 80 to 100 cube shaped droppings every night, a unique phenomenon in the animal kingdom. Their intestines have varying elasticity that molds the feces into cubes during the final stages of digestion. Wombats stack these cubes on rocks and logs to mark territory, and the cube shape prevents them from rolling away. Scientists studied this for years before discovering the intestinal mechanics.
Wombats have incredibly hard, thick rumps made of cartilage, bone, and tough skin that they use as shields and weapons. When threatened in their burrows, a wombat blocks the tunnel with its rear end and crushes predators' skulls against the burrow ceiling. This defensive tactic has killed dingoes and foxes. The rump can withstand tremendous force without injury.
Unlike kangaroos with forward facing pouches, wombats have backward facing pouches that open toward their rear. This prevents dirt from entering the pouch and covering the baby while the mother digs extensive burrow systems. Female wombats dig constantly, and a backward pouch is essential for protecting joeys during construction and maintenance of tunnels.
Despite appearing slow and stocky, wombats can run up to 25 mph in short bursts when threatened. This speed surprises predators and allows wombats to reach their burrows quickly. Wombats typically move slowly to conserve energy but can accelerate rapidly when needed. Their powerful legs propel their heavy bodies at impressive speeds.
Wombats dig burrow systems that can extend up to 650 feet with multiple entrances, tunnels, and sleeping chambers. These underground networks maintain stable temperatures and protect wombats from extreme heat and cold. Multiple wombats sometimes share burrow systems. Digging is so important that wombats have ever growing teeth and powerful claws.
Wombats and koalas are the closest living relatives despite looking completely different. Both are marsupials that evolved from a common ancestor. They share similar digestive systems optimized for tough plant material and both have backward facing pouches. Genetic studies confirm their close relationship, though wombats live underground while koalas live in trees.
Wombats have lived in Australia for over 20 million years, evolving as unique burrowing marsupials.
Aboriginal Australians have known wombats for tens of thousands of years, featuring them in stories.
European settlers initially viewed wombats as agricultural pests, leading to culling programs.
Giant wombats the size of rhinoceroses existed until about 50,000 years ago.
The cube poop mystery baffled scientists until 2018 research explained the intestinal mechanics.
Research finally explained cube poop formation through intestinal elasticity variation in 2018.
Studies documented wombat burrow systems extending up to 650 feet with multiple chambers.
Scientists confirmed wombats and koalas are closest living relatives despite different lifestyles.
Research showed wombats can run up to 25 mph in short bursts despite stocky appearance.
Studies documented the skull crushing defensive technique using armored rumps.
Cube poop made wombats viral internet sensations and won researchers the Ig Nobel Prize.
Australian conservation programs use wombats as flagship species for habitat protection.
Wombats became symbols of Australian resilience and uniqueness in wildlife.
Children's books and media feature wombats as beloved Australian characters.
Wombat tourism contributes to Australian wildlife conservation funding.
Before European settlement, wombats thrived across eastern and southern Australia without major threats. Their burrow systems provided ecosystem services for many species. Aboriginal Australians coexisted with wombats for tens of thousands of years.
After European colonization, wombats faced culling as pests, habitat destruction, and introduced diseases. Sarcoptic mange now kills thousands painfully. Vehicle collisions are a major mortality cause. The northern hairy nosed wombat declined to about 300 individuals, though conservation efforts are slowly helping recovery.
Wombats are the only animals in the world that produce cube shaped poop to mark their territory
A wombat's hard rump can crush a predator's skull by blocking burrow entrances and squeezing upward
Despite looking slow, wombats can run up to 25 mph in short bursts to escape predators
Wombat pouches face backward so dirt doesn't get in while the mother digs underground burrows
Wombats and koalas are closest living relatives despite living in completely different habitats
A wombat can dig burrow systems extending up to 650 feet with multiple tunnels and chambers
Sarcoptic mange threatens wombat populations, causing painful deaths
Vehicle collisions kill thousands of wombats annually on Australian roads
Climate change and drought affect vegetation wombats depend on
Wombat burrows provide shelter for dozens of other species during fires and heat
The northern hairy nosed wombat is critically endangered with only about 300 remaining
How much do you know? Take this quick quiz to find out!
Only animal with cube poop. Intestinal elasticity variations create 80 to 100 cubes nightly.
Rumps crush predator skulls. Armored rear ends block burrows and kill dingoes.
They run 25 mph. Stocky appearance hides surprising speed when threatened.
Pouches face backward. Dirt cannot enter while mothers dig extensive tunnel systems.
Koalas are closest relatives. Despite different habitats, they share common marsupial ancestors.
Burrows extend 650 feet. Underground cities have multiple entrances and sleeping chambers.
Wombats have intestines with varying elasticity that mold their feces into cubes during digestion. They produce 80 to 100 cubes nightly and stack them on rocks to mark territory. The cube shape prevents the poop from rolling away, making it an effective territorial marker.
This article is reviewed by the Pagefacts team.
Editorial Approach:
This article reveals wombats are the only animals with cube shaped poop formed by intestinal elasticity, explains how their armored rumps crush predator skulls against burrow ceilings, and shows how they are koalas' closest living relatives.
Explore more fascinating facts in this category

Crabs are crustaceans found on every continent with over 7,000 species. Discover why crabs walk sideways, trade shells, and grow claws stronger than jaws.

Spiders produce silk five times stronger than steel by weight. Discover how spiders fly using electric fields, see in color, and engineer perfect webs.

Jaguars possess the strongest bite of any big cat and kill prey by crushing skulls rather than suffocating. They love swimming and hunt caimans in rivers.