Top 5 Colonial Organisms

5. Ants

Cousins to the bees and even closer to the wasps, ants are arguably the most successful animals on Earth, far more aggressive than most other colonial organisms and outcompeting many other species large and small with their superior numbers. Many are capable of cultivating their own edible fungi, plant life or even insect “cattle.” Some may link their bodies together to form temporary bridges, rafts and protective barriers. Some can even overwhelm and kill vertebrates thousands of times their size, in some cases driving nearly all other life from their territory. Whatever problem a colony may face, only a single member needs to find the solution and the rest will follow, thousands of workers and soldiers collectively solving problems like a single massive, mobile brain…a mobile brain with a million teeth.
4. Termites

Whereas many ants seem like a formidable army of conquerors, termites are more like futuristic, utopian pacifists. Symbiotic microorganisms allow termites to derive sustenence from plant cellulose, making them some of the few creatures that can feed entirely on wood. Other species may simply grow their own gardens of symbiotic fungi as food, but in any case, termites are virtually never aggressive or carnivorous. Instead, they spend most of their lives sealed within their nests, some of which put human engineering to shame with their complex, high efficiency architecture. While termites share the same castes as ants – queens, workers, soldiers and a winged reproductive caste – they are actually categorized as a highly unusual group of cockroaches.
3. Mole Rats

The only known vertebrates with a colonial structure like that of ants or termites are two species of “mole rat” or blesmol, the famous Naked mole rat and lesser known, fuzzier Damaraland mole rat. These bizarre rodents build subterranean communities where the “queen” is kept fertilized by her own sons, while her daughters are sterilized by hormones in her urine and function as a worker caste. Naked mole rats are especially well adapted to this insect-like existence; their own carbon dioxide turns their tunnel systems into a highly toxic and constantly hot environment, but their lack of pain reception and a “cold blooded” metabolism (unique among mammals) allow them to thrive comfortably in these hostile conditions.
2. Pistol Shrimp

The Alpheidae or “pistol shrimp” are well known to marine biologists for their amazing biological weaponry; one of the two front claws is highly enlarged, and rather than functioning as a pincer, its joints have evolved to generate a sort of “sonic blast” when snapped shut, capable of paralyzing fish and even breaking glass. Most of these impressive invertebrates live solitary lives, but a few species are the only eusocial crustaceans and only eusocial sea life known to man. These bees of the sea employ living sponges as their “hives,” with a single queen and up to several hundred offspring, including both a worker caste with normal claws and a soldier caste bearing the group’s trademark snapping cannons.
1. Hydrozoans

Close cousins to the corals but far more elaborate, Hydrozoa are made up of attached individuals so specialized that they function more like organs forming one “body,” blurring the line between a colony and a single animal. The most famous Hydrozoan is the Portuguese Man O’ War, which consists of four different polyps: one forms the gas filled “float” while others form the venomous tentacles, stomach-like feeding polyps and special reproductive polyps. Other hydrozoan species may form stationary coral-like colonies, swimming chains and many other strange shapes. Some in the deep ocean are luminous, and one even dangles bright lures to attract its prey.
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