Centipedes are arthropods belonging to the class Chilopoda of the subphylum Myriapoda. They are elongated metameric creatures with one pair of legs per body segment. Centipedes are carnivorous, venomous predators that feed on smaller arthropods and other small animals. There are around 3,300 species of centipedes worldwide, found in a variety of habitats from tropical rainforests to deserts.
Centipedes have developed a reputation as aggressive and frightening creatures due to their large size, speed, venomous bite, and tendency to show up unexpectedly in homes or gardens. Their many fast moving legs create an intense, darting motion that can startle humans used to dealing with slower moving insects. But are centipedes truly aggressive by nature, or are they simply acting defensively and instinctively to survive threats in their environment?
Anatomy and Physical Traits
Centipedes have elongated, flattened bodies divided into a head, trunk, and tail. Their bodies are made up of 15 to 191 segments, each bearing a single pair of legs. This gives them an overall length ranging from a few millimeters to over 30 centimeters. Despite the name “centipede” meaning “100 legs”, no known centipede has exactly 100 legs.
The legs are slender, jointed, and terminate in a single claw. The legs on the first trunk segment are modified into venom claws called forcipules. These claws curve forward over the head and can inject venom into prey items. The legs toward the rear are used for locomotion.
Centipedes have a single pair of antennae on their head and clusters of simple eyes along the margins of their head and trunk. These eyes enable them to detect light and movement, but cannot form images. Centipedes breathe through small openings called spiracles located along the sides of their body segments.
Habits and Behavior
Centipedes are largely nocturnal, preferring to hunt at night and remaining hidden during the day. They typically reside in damp, cool microhabitats such as loose soil, leaf litter, rotting logs, stones, and other natural debris. Some species live their entire lives underground. When active, they use their many legs to quickly dart along in search of food.
Despite their frightening appearance, centipedes are themselves prey for many animals. Their slender bodies are vulnerable to attack from mammals, reptiles, amphibians, birds, and other arthropods. As a result, centipedes have developed several defensive adaptations:
- They can move rapidly to escape threats.
- Their cryptic coloration helps them blend into their surroundings.
- They will flee to cover when disturbed.
- They will deliver painful and venomous bites to attackers.
The bite of larger centipede species can cause intense pain, swelling, discoloration, numbness, and other symptoms in humans. However, centipede venom is not considered deadly to humans except in rare cases of severe allergic reaction.
Hunting and Feeding
Centipedes are voracious predators, feeding on a variety of smaller arthropods and other invertebrates. Prey items include insects, spiders, millipedes, silverfish, earwigs, snails, worms, and others. Larger centipede species may feed on small reptiles, amphibians, or mice.
Centipedes are equipped with several adaptations that aid their predatory lifestyle:
- Their many legs allow them to move rapidly to catch prey.
- Their pincer-like venom claws can quickly grasp small animals.
- Venom paralyzes prey and aids digestion.
- Their senses detect prey through touch, vibration, and chemicals.
To attack, the centipede grasps prey using its front legs and venom claws. It then delivers venom through openings near the tips of the claws. The venom contains toxins that can paralyze and kill small prey rapidly. The centipede then uses additional legs to manipulate the prey into position for eating. Strong jaws allow it to tear the prey apart and consume it.
Reproduction and Life Cycle
Centipedes may reproduce sexually or asexually, depending on the species. In sexual reproduction, males deposit spermatophores for females to take up into their reproductive tract. The female then lays between 10 to 300 eggs in a protected site such as underground or under rocks or bark. The eggs hatch into young centipedes, which resemble tiny versions of the adults.
Centipedes go through simple metamorphosis with three life stages: egg, young, and adult. The young centipedes Molt their outer skeleton several times as they grow, eventually reaching adult size and sexual maturity. The average centipede lifespan is 3-7 years, but some species can live up to 10 years or slightly longer.
Some female centipedes care for their eggs and young, while others abandon them after egg laying. Parental care where it occurs may involve guarding the eggs, feeding young centipedes, and protecting them until they disperse. This extra protection may improve survival rates for the young.
Habitats and Distribution
Centipedes inhabit a diverse array of habitat types worldwide. They are found in tropical and temperate forests, savannas, prairies, swamplands, dunes, mountains, caves, urban zones, and elsewhere. Since they require moisture, they tend to be concentrated in damp microhabitats within these ecosystems. Some examples include:
- Soil – especially moist, loose soil and rotting leaves
- Leaf litter and compost piles
- Under stones, logs, bark, and other natural debris
- Rotting wood and stumps
- Cave floors and walls
- River and lake margins
- Coastal dunes
In addition, many species live exclusively underground. Centipedes are found on every continent except Antarctica. They occur across southern Canada, throughout the continental United States, Mexico, Central and South America, southern Europe, Africa, Asia, Australia, and various island groups. The tropics harbor the highest diversity of centipede species.
Adaptations and Ecology
As successful predators adapted to a broad range of environments, centipedes exhibit many key evolutionary adaptations:
- Venomous claws – Allow them to subdue larger prey.
- Cryptic coloration – Provides camouflage from predators and prey.
- Photophobic – Avoid light to hide from threats.
- Low metabolic rate – Enables survival in low resource environments.
- Cold tolerance – Allows survival in cool climates; heat sensitive.
- Water regulation – Adapted to moist environments.
Centipedes play an ecological role both as predators and as prey. As predators, they help regulate populations of small invertebrates. As prey, they provide an important food source for larger animals. Their diversity and adaptation to nearly all terrestrial ecosystems is evidence of their ecological success.
However, some centipede traits can pose problems from a human perspective. Their appearance evokes fear and dislike in many people. Their bites can cause mild to severe pain. And their fast, darting movement helps them escape detection as they can easily startle people. These factors contribute to their undeserved negative reputation.
Threats and Conservation
Despite their adaptability, some threats face various centipede species:
- Habitat loss – From human development, agriculture, logging, etc.
- Environmental pollution – Can degrade their soil and moisture habitats.
- Climate change – May alter ecosystems upon which they depend.
- Introduction of non-native species – Can disrupt native ecosystems.
- Use in traditional medicine – Leads to overharvesting of some species.
However, no centipede species are considered globally threatened or endangered currently. Their adaptable biology enables most centipedes to withstand some degree of habitat modification by humans. But conservation of natural habitats and wise land management practices may help protect the ecological integrity of sensitive sites where specialized endemic centipede populations occur.
Centipedes as Pets
Despite their frightening appearance, some centipede species are kept as exotic pets by arachnid and other specialty enthusiasts. Scolopendra and Ethmostigmus species are the most popular and suitable centipede pets. Their proper care requires:
- A secure, well-ventilated terrarium with proper humidity and refuge sites.
- Substrates that hold humidity and allow burrowing such as peat moss or coconut fiber.
- Adequate moisture provided through misting, moist substrate, and a small water dish.
- Appropriate tropical or subtropical ambient temperatures from 70-80 °F.
- Hiding places such as bark, rocks, logs, live plants.
- Regular feeding of live insects appropriate to the centipede’s size.
- Careful handling to avoid bites from larger species.
However, centipedes are not ideal pets for beginners due to their specialized care requirements, potential to escape, and medical risks from bites. But for experienced centipede owners willing to provide proper habitat conditions, they can be interesting animals to maintain in captivity.
| Centipede Species | Origin | Average Size | Life Span |
|---|---|---|---|
| Scolopendra alternans | Florida to Texas | 3 inches | 3-5 years |
| Scolopendra heros | Arizona, New Mexico, Texas | 6-8 inches | 7-10 years |
| Scolopendra subspinipes | Tropics of South Asia, Australia, Pacific | 3-5 inches | 4-6 years |
| Ethmostigmus rubripes | Central America and Northern South America | 4-5 inches | 5-8 years |
Conclusion
In summary, centipedes have an undeserved reputation as highly aggressive animals. In reality, most centipede species are not aggressive by nature. They are not equipped to hunt the large animals that humans and pets represent. Their venomous bites and defensive behaviors are adaptations to help them survive predation by larger animals in nature.
Centipedes will only bite humans in self-defense when threatened or unintentionally handled. Otherwise, they are timid and inclined to flee potential danger. Their darting motions and alarming appearance can startle people unfamiliar with their natural history and behavior. But through education and properly securing homes against accidental invasion, most negative incidents with centipedes can be avoided through coexistence and tolerance.
With over 3,000 diverse species filling vital ecological roles, centipedes are an integral component of most terrestrial ecosystems. They pose little threat to humans, and most species should be regarded with interest and appreciation for their unique biology rather than fear, dislike, and misconceptions. Their remarkable adaptations allow centipedes to run, hide, and survive in nearly any terrestrial habitat on Earth.
