Mesenchytraeus solifugus
| Mesenchytraeus solifugus | |
|---|---|
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| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Annelida |
| Class: | Clitellata |
| Subclass: | Oligochaeta |
| Order: | Haplotaxida |
| Family: | Enchytraeidae |
| Genus: | Mesenchytraeus |
| Species: | M. solifugus |
| Binomial name | |
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Mesenchytraeus solifugus (Emery, 1898) |
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Mesenchytraeus solifugus is a species of Oligochaete worms commonly called ice worms.
Adult ice worms measure around 15 mm in length and about 0.5 mm in diameter. Their fluid and flexible body squeezes through air holes and tiny crevasses in ice.
It is believed that the ice worm has a life span of five to ten years.
Ice worms have heavy pigment, absorbing all colours or reflecting dark brown. Yet strangely, they burrow into the glacier to avoid strong sunlight. Carlo Emery named the species solifugus in 1898, meaning "fleeing from the sun".
Ice worms populate coastal glaciers in North America from Alaska to northern Washington State.
The worms appear on the surface in high density; researchers have counted between 30 and 300 ice worms per square metre. On Byron glacier alone, researchers estimate the worms numbered around 30 million. The total number in all the coastal glaciers easily surpasses the entire human population.
Mesenchytraeus solifugus have a very narrow acceptable temperature range. Ice worms freeze at around −6.8 C (19.8°F), and their bodies decompose after continuous exposure to temperatures above 5 C (41 °F). This decomposition process, known as autolysis, occurs when the cells produce digestive enzymes and self-destruct. The body literally melts.
They are the only known worm to spend their entire life in temperatures near 0 C (32°F). Even if other places are equally cold, ice worms never venture onto any other terrain. They eat the abundant snow algae and pollen carried by the wind.
In the summer, ice worms follow a diurnal cycle—at the first light in the morning, they sink into the glacier. A few hours before sunset, they poke out from the snow.
Ice worms can still be found in broad daylight. Many of them gather in glacial ponds or small streams. Scientists believe the water blocks out the sun's longer wavelengths which the worms avoid, and the freezing water provides the worms with comfortable temperature.
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Wikipedia