Palolo Worms facts and info. Know Palolo Worms weight-reduction plan, habitat, behaviour taxonomy, and so on See attention-grabbing facts of Palolo Worms in our animal facts archive.
Scientiﬁc identify: Eunice species
What do they seem like? These worms show the segmentation that’s frequent to all of the annelids (polychaetes, earthworms, and leeches). When totally grown, they are often roughly 1 m in size. The head finish bears sensory tentacles and advanced jaws.
Where do they dwell? Palolo worms are discovered world wide in tropical and subtropical seas. They usually dwell beneath the low-water mark in coral and rocky crevices, though some species construct burrows within the mud or sand of the seabed.
For a lot of the 12 months, the Palolo worm, protected in its rocky or coral crevice, seems to be like every other sedentary polychaete, its physique divided into a protracted sequence of equivalent segments. The worm on this stage of its life is named the atoke, which is a####ual and can not breed. However, with the altering seasons, the time is correct for breeding, and quickly the worm’s look undergoes a radical transformation. From the rear of the worm, new, extremely modiﬁ ed segments begin to develop, till a protracted chain of these equivalent items hangs from the rear of the atoke. This new and fully completely different part of the worm is named the epitoke, and it’s this half that’s concerned within the strategy of replica.
The segments of the epitoke are precise replicas of each other, and every is filled with eggs and sperm. On the floor of the epitoke section there’s a single eyespot; nevertheless, this isn’t an organ for discriminating shapes and element, however quite for telling evening from day.
Huge numbers of these worms, with their epitokes totally fashioned, wait of their refuges for a speciﬁ c cue to spawn. The cue is the moon, and in October or November, firstly of the final lunar quarter, all of the worms release their epitokes on the identical time.
The epitokes, freed from the atoke, swim with undulations of their spaghetti-like kind to the floor of the ocean, and because the solar rises (detected by the eyespot), they burst, releasing their eggs and sperm. The sea, shut to shore, shall be a soup of gametes. The eggs are fertilized quickly, and by the subsequent day, tiny larvae have fashioned.
After drifting for 2 or three days, these offspring start to settle and ﬁ nd rocky hideaways of their very own the place they’ll become grownup worms in preparation for the subsequent 12 months’s mass spawning. The atoke, nonetheless in its burrow, will regenerate a brand new epitoke for the next 12 months’s breeding season.
The polychaete worms, of which the Palolo worms are one sort, are quite common invertebrates, however as with many smaller animals, their secretive lives end in being neglected by the informal observer. There are about 9,000 species of these worms, that are principally marine, though a number of species are present in soil and freshwater. Most are quite small animals, however the Palolo worm, Eunice gigantean, might be over three m in size. Some of the species are superbly coloured in shimmering reds, pinks, and greens. They might be energetic detritivores, scavengers or hunters (errant polychaetes), or burrow dwelling (sedentary polychaetes). It has been calculated that the burrowing polychaetes dwelling on the seabed flip over greater than 4,500 tonnes of mud per hectare of seaﬂ oor annually.
The synchronized release of the epitokes by Palolo worms is significantly anticipated by the people who dwell within the areas the place these animals happen. Eunice viridis (the Samoan Palolo worm) is a selected favourite among the many people of Samoa, who look forward to spawning earlier than wading into the shallows with torches to accumulate the spaghetti-like epitokes with no matter gear they’ll ﬁ nd. Many merely eat the epitokes uncooked as they’re taken from the water, though nice portions are taken ashore the place they’re boiled, baked, stewed, or fried and eaten in a variety of dishes. Epitokes on toast is a selected favourite.
A relative of the Samoan Palolo worm, Eunice fucata (the Atlantic Palolo worm), synchronizes its breeding for the second or third day earlier than the third quarter of the moon, someday in June or July.
Another species of polychaete, Odontosyllis enopla, discovered within the West Indies and Bermuda, additionally swarms. However, on this species, there are separate males and females. In the summer time, 50 to 60 minutes after sundown and up to 12 days following a full moon, the worms swim from the seabed to the floor the place they begin to glow. They swim round and round one another, forming small circles of sunshine within the water.
Epitoky and swarming is sort of frequent among the many polychaetes. This phenomenon makes it potential for a inhabitants of worms, which dwell out their grownup lives on the seabed in dispersed populations, to come collectively brieﬂy for the needs of replica. Swarming is a means of accelerating the possibilities of fertilization.
The synchrony of the worm’s breeding is managed by the lunar cycle—the impact the moon’s gravitational ﬁ eld has on the earth. Exactly what the worms are detecting is unknown, however many animals, particularly these within the seas, synchronize their actions with the waxing and waning of the moon. The inﬂ uence of the moon on the earth follows a predictable sample; due to this fact, it’s unsurprising that many organisms have taken to utilizing it as a type of timer.