Scientists Say: Caecilian
Some of these legless amphibian rebels produce a milk-like liquid for their young
Caecilians are a bizarre group of amphibians that nourish their young with their own body tissues.
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Caecilian (noun, “suh-SEE-lee-uhn”)
Caecilians are a group of worm-shaped amphibians.
Caecilian means “blind ones” in Latin. The name fits: many species of caecilians lack eyes altogether. Those with them have simple eyes that only detect dark and light. Caecilians experience the world through their other senses — especially their sense of smell. A pair of tentacles on their heads “tastes” the air, detecting chemicals.
Caecilians live in wet tropical regions around the world. Many caecilians spend most of their lives underground. Some thrive in soil and streambeds, using their worm-like bodies to burrow through mud. Other species are fully aquatic. These wiggle through the water like eels.
Caecilians appear snake-like because they lack limbs. But they are amphibians, not reptiles. Their slick, slimy skin allows oxygen to diffuse right into their blood — a feature of amphibians. Despite this ability, most caecilians have lungs.
Caecilians are usually carnivores, or meat-eaters, that hunt for their food. Their prey varies by species. Caecilians might eat insects, fish, snakes and even small mammals.
Some caecilians lay eggs, just like most amphibians. But many species give birth to live young, like mammals. And many caecilians feed their young in unusual ways. One of those ways was just discovered in 2024. Despite being amphibians, one species — the ringed caecilian (Siphonops annulatus) — makes a milk-like liquid for offspring.
Some caecilian young feed upon tissues from their mother’s body. For example, caecilians that give birth to live young sometimes grow tissues inside their bodies to feed their unborn young. Other species — particularly egg-layers — might grow a special layer of fat on their bodies. Young or unborn caecilians use their teeth to scrape these layers from their mothers, which nourishes them as they grow.
In a sentence
In 2024, ringed caecilians became the first amphibian known to produce milk-like liquid for their young.
