Australia is home to some of the most unusual creatures on earth. This biodiversity extends to both its land and sea animals. But not every creature lands up in promotion brochures because of the cute factor. One such creature is the penis worm, an animal that looks as unusual as its name.
The penis worm also goes by the name of spoon worm, or echiuran. Unfortunately, there is no ongoing campaign to save the penis worm despite the fact that they are an integral member of the ecosystem.
True, They Do Look Questionable
These invertebrates have been classified by taxonomists in various ways. While some have declared them unique and belonging to their group, modern researchers consider the penis worm as an annelid, without a definite segmentation. The exact figure of existing species is not yet known, but it is estimated that there are around 236 species of the penis worm.
The largest of the penis worms can reach an incredible length of two meters. The trunk is muscular and sausage-shaped while there is a tongue, or proboscis, at the front. The penis worm moves through wave contractions.
The penis worm lives in mud and marine sand in U-shaped holes. Several species also swell in rocks. And they are incredibly widespread. While they are found on seashores, they have also been discovered at depths of 6,000 meters.
One such species of the penis worm, Ochetostoma Australians is commonly found along the shorelines of NSW and Queensland. It slips out of the burrows in the sandy shoreline to feed on organic matter.
Their feeding activity is interesting to behold. The penis worm forms a star shape over the surface, spreading from the start of its burrow.
Bonella viridis, another species, exhibits a striking variance between the male and the female. While the female is larger at 15 centimeters, the males grow to a mere 1 to 3 millimeters. The larvae are undifferentiated sexually. Their ultimate sexual identity depends on external factors.
The larvae change into male dwarfs if they are exposed to females. But they metamorphose into females in the absence of females in their vicinity.
The males function as merely gonads and rely on the females for their needs.
The Importance Of The Penis Worm
The penis worms are an important member of the marine environment and accomplish a variety of vital ecological functions. They are rightly called ecosystem engineers. Such organisms indirectly or directly control the accessibility of food, shelter, and other resources, for other species, thus ensuring their survival.
They do so by changing the features of habitats physically. For instance, they create and maintain burrows that are used by other species.
The penis worm also has various symbiotic animals such as bivalve mollusks and crustaceans that reside in deep burrows. These creatures are mutually beneficial to one another. Animals from 8 different groups of animals link with the penis worm’s burrows or with the species that inhabit the rocks. And there could be many more undiscovered animals that have a synergetic relationship with the penis worm.
The spoon worm is also beneficial to humans. their feeding patterns and burrowing habits rework and aerate sediments. This can reduce the impact of wastewater over the seabed along the Californian coastline, as noted by researchers.
They are eaten by varieties of fish, deep-water sharks, including the hound shark, and the commercially significant Alaskan plaice. In the Bering Sea, mammals like the walrus, and the otter feast on them. In Queensland, the eastern curlew also feeds on the penis worm. It is a vital part of the diet of this critically endangered bird.
People in Southeast and East Asia also eat them raw or fermented.
These invertebrates of Australia are a vital part of its ecosystem but have remained unknown and unappreciated. But they remain vital and their impact on their population can affect many other species that are either vulnerable or endangered.