Lancelet is fish-like sea animals,which occur most often in shallow subtropical and temperate latitudinal waters. They live on the bottom, in pure gravel or sand. The length of these creatures is usually less than 5 cm, although some individuals reach 6-9 cm. What is the significance of the lancelet in nature? It turns out very large.
Large populations
In some places, lancelet populations canbe pretty big. For the Branchiostoma floridae species, this figure can be up to several thousand individuals per square meter. Sometimes animals leave their burrows and move for a short distance, and then quickly bury themselves in the back end of the substrate. Lancelet floating with side waves that provide direct movement.
Features of the structure
Muscles of the body wall form myotomes,located along most of the body. The notokord is an elastic flexible rod, characteristic of one or more life stages of all chordates, extends beyond the myotomes both in front and behind, providing support, and helps to keep the body in burrowing. These marine invertebrates are inhabitants of tropical seas. As in the case of all chordates, this is a group that includes the shell, chord, hollow spinal cord, nerve and pharyngeal cleft (pharyngeal pouches).
Lancelet have a wedge shape, tapered atboth ends. Cephalochordates retain their notacord throughout their life, unlike vertebrates, which have chords only during the early (embryonic, larval) stages. These are suspended feeders. Water is supplied to the mouth and pharynx, passes through the pharyngeal gills of the gill into the surrounding atrium and leaves the body through the abdominal atriopore. Currents are generated by the movements of the pharyngeal cilia, not the muscles. The delivery system includes several structures that prevent large particles from entering the inside of the mouth. Food particles get into the mucus and move by cilia in the mouth.
Heterosexual creatures
Lancelet - are heterosexual creatures.Spawning occurs during or after sunset. Oocytes and sperm are released into the water that flows from the atrium, thus fertilization will be considered external. The resulting embryos develop rapidly into larvae. They swim in the water column, remaining there in the form of plankton for several weeks (the duration depends on the temperature). To eat, the larvae first swim up, then hover or slowly sink down by the mouth, absorbing plankton.
Long-livers
Development from the larval to juvenile stage usually occurs gradually. Lancelet life is surprisingly considerable, from 2 to 5 years, depending on the type and breeding season.
What is the significance of lancelet in nature?
In China, people use lanceulums asfood. They are also an important food for feed fish and small crustaceans. In total, there are about 30 species of these marine animals; nevertheless, in Asia, lancelet is harvested commercially as food, which is eaten both by humans and domesticated animals.
What is the significance of lancelet in nature and lifeman? These creatures are an important object of study of zoology, since they provide an opportunity to learn more detailed information about the origin of vertebrate animals. Lancelets also play a key role in certain food chains, sometimes dwelling on thousands of square hectares of sand, they contribute to the diversity of biological forms and behaviors that make nature even more fascinating to people.
Small but strong
Lancelet usually remain buried in the sandand only the head protrudes to filter the feed and breathe through the gill slits. They swim quite swiftly. Like all vertebrates, they have a nerve cord that runs along the back, pharyngeal crevices and tail, which runs along the anus. However, unlike vertebrates, the dorsal nerve cord is not protected by bone, but by a simpler notochord consisting of a cylinder of densely packed cells that form a reinforced stem.
Lancesets also have oral tendrils,thin tentacle-like strands that hang in front of the mouth and act as sensory devices and as a filter for water flowing into the body. Water exits the body through the atriopore. They have a well-developed circulatory system, but do not have blood cells, the main heart and kidneys. The brain and sense organs are poorly developed. The value of lancelet in nature is very large - these creatures help to expand biological diversity, both by themselves and as food for other marine life.
An important point for tracking evolution
What is the significance of lancelet in nature?The lancelet is an intriguing benchmark for tracking the evolution and adaptation of vertebrates. Although they are separated from modern vertebrates for more than 520 million years, their genomes contain information about evolution, especially how vertebrates used old genes for new functions.
This is a kind of archetypal form of vertebrates.What is the meaning of lancelet in nature? This small, translucent, fish-like animal is the closest living invertebrate relative of vertebrates, which is why it is of great interest to marine zoologists.
