Holothurians, or sea cucumbers, can be called one of the strangest, most interesting and unusual inhabitants of the waters. From the point of view, they are animals, but their characteristics and lifestyle lead some to think that they are closer to plants. However, this is not at all true, but this does not stop one from wondering how evolution even created this bizarre creature.
Interesting facts about sea cucumbers
- In total, there are as many as 1150 holothurians in the world species, many of which are edible.
- Judging by archaeological finds, the first sea cucumbers appeared on Earth about 440 million years ago. They are older than many dinosaur species.
- The bodies of sea cucumbers are symmetrical, but very distinctive. For example, our bodies are symmetrical on two sides, while theirs are five.
- It is impossible to overestimate the importance of holothurians for the world ecology. They process 80-90% of all plant and animal remains that settle on the bottom of the oceans (interesting facts about ecology).
- No matter how funny it may sound, but sea cucumbers breathe with the help of a cloaca, or anus. Through it, they draw water into their body, from which they already absorb oxygen.
- The karapus fish hides inside the holothurians at a time when it is not looking for food. Moreover, it penetrates into it through the same aforementioned opening of the body.
- Sea cucumbers feed by sucking sand and soil into the body, absorbing useful substances from it and throwing waste back.
- These amazing creatures can make their body both rigid and almost liquid. Thanks to this, they can seep into the narrowest gaps.
- Sea urchins and starfish are the closest relatives of holothurians (interesting facts about starfish).
- Sea cucumbers, the largest species in their mature state, can reach a length of up to 5 meters, and the smallest – only 3 centimeters.
- The mouth of the holothurian is surrounded by small tentacles, which can be up to 30 pieces.
- Some types of sea cucumbers, in case of danger, throw out their insides along with a liquid that is poisonous to most other marine organisms.
- In some Asian countries, dried sea cucumbers are used as a folk pain reliever.
- If a sea cucumber suddenly loses an intestine, it can grow a new one in a month or two.
- No bacteria have ever been found in the cells of holothurians (interesting facts about bacteria).
- Because of popularity of edible sea cucumbers in some countries, they are purposefully bred on special marine farms.
- For a year, sea cucumbers of medium-sized species (about the size of a human hand) sift through their bodies about 150 tons of sand and soil.
- The life span of holothurians can be up to 10 years.
- Most of their species spend their entire lives on the bottom, but some live right in the water column without sinking down.
- In traditional Chinese medicine sea cucumbers actively apply are still used today, as in local cuisine.