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Apolemia Rubriversa
''Apolemia'' is a genus of siphonophores. It is the only genus in the monotypic family Apolemiidae. Despite appearing to be a single multicellular organism, they are actually a floating colony of polyps and medusoids, collectively known as zooids. Research history The genus ''Apolemia'', named by Baltic-German physician and naturalist Johann Friedrich von Eschscholtz, was first documented in 1815 with the discovery and description of ''Apolemia uvaria'' (the "string jellyfish"), by French naturalist Charles Alexandre Lesueur off the coast of Europe. It was displaying a net-like feeding pattern in the pelagic zone, and was documented to have rows of nematocysts. Few species have been well-defined within the genus otherwise. In 2020 researchers working off the coast of Western Australia came across an ''Apolemia'' which had coiled itself into a spiral form. The outer "ring" was estimated to be 47 meters (154 feet) long, with an estimated total length of 119 meters (390 feet). Thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apolemia Uvaria
''Apolemia uvaria'', commonly known as string jellyfish, barbed wire jellyfish,Jones, Georgina. ''A field guide to the marine animals of the Cape Peninsula.'' SURG, Cape Town, 2008. and long stringy stingy thingy, is a colonial siphonophore. As with all siphonophores, string jellyfish look and function much like a single organism, but each ''Apolemia uvaria'' is a colony of specialised minute organisms (zooids), permanently attached to each other and physiologically connected to the extent that they cannot survive alone. String jellyfish are colonial animals that may reach 3 m in total length and have a diameter of 2–5 cm. The colony is formed of a central string, bearing groups of pink and white tentacles, which clump together or extend. The whole colony has a gas float at the front and a set of swimming bells.Wrobel D. & Mills C. 2003. ''Pacific Coast Pelagic Invertebrates'': a guide to the common gelatinous animals. Sea Challengers. This colonial animal is pelagic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apolemia Vitiazi
''Apolemia'' is a genus of siphonophores. It is the only genus in the monotypic family Apolemiidae. Despite appearing to be a single multicellular organism, they are actually a floating colony of polyps and medusoids, collectively known as zooids. Research history The genus ''Apolemia'', named by Baltic-German physician and naturalist Johann Friedrich von Eschscholtz, was first documented in 1815 with the discovery and description of ''Apolemia uvaria'' (the "string jellyfish"), by French naturalist Charles Alexandre Lesueur off the coast of Europe. It was displaying a net-like feeding pattern in the pelagic zone, and was documented to have rows of nematocysts. Few species have been well-defined within the genus otherwise. In 2020 researchers working off the coast of Western Australia came across an ''Apolemia'' which had coiled itself into a spiral form. The outer "ring" was estimated to be 47 meters (154 feet) long, with an estimated total length of 119 meters (390 feet). Thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrozoan Genera
Hydrozoa (hydrozoans; from Ancient Greek ('; "water") and ('; "animals")) is a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water. The colonies of the colonial species can be large, and in some cases the specialized individual animals cannot survive outside the colony. A few genera within this class live in freshwater habitats. Hydrozoans are related to jellyfish and corals, which also belong to the phylum Cnidaria. Some examples of hydrozoans are the freshwater jelly ('' Craspedacusta sowerbyi''), freshwater polyps ('' Hydra''), ''Obelia'', Portuguese man o' war (''Physalia physalis''), chondrophores (Porpitidae), and pink-hearted hydroids ('' Tubularia''). Anatomy Most hydrozoan species include both a polypoid and a medusoid stage in their life cycles, although a number of them have only one or the other. For example, ''Hydra'' has no medusoid stage, while '' Liriope'' lacks the polypoid st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apolemiidae
''Apolemia'' is a genus of siphonophores. It is the only genus in the monotypic family Apolemiidae. Despite appearing to be a single multicellular organism, they are actually a floating colony of polyps and medusoids, collectively known as zooids. Research history The genus ''Apolemia'', named by Baltic-German physician and naturalist Johann Friedrich von Eschscholtz, was first documented in 1815 with the discovery and description of ''Apolemia uvaria'' (the "string jellyfish"), by French naturalist Charles Alexandre Lesueur off the coast of Europe. It was displaying a net-like feeding pattern in the pelagic zone, and was documented to have rows of nematocysts. Few species have been well-defined within the genus otherwise. In 2020 researchers working off the coast of Western Australia came across an ''Apolemia'' which had coiled itself into a spiral form. The outer "ring" was estimated to be 47 meters (154 feet) long, with an estimated total length of 119 meters (390 feet). Thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ambush Predator
Ambush predators or sit-and-wait predators are carnivorous animals that capture their prey via stealth, luring or by (typically instinctive) strategies utilizing an element of surprise. Unlike pursuit predators, who chase to capture prey using sheer speed or endurance, ambush predators avoid fatigue by staying in concealment, waiting patiently for the prey to get near, before launching a sudden overwhelming attack that quickly incapacitates and captures the prey. The ambush is often opportunistic, and may be set by hiding in a burrow, by camouflage, by aggressive mimicry, or by the use of a trap (e.g. a web). The predator then uses a combination of senses to detect and assess the prey, and to time the strike. Nocturnal ambush predators such as cats and snakes have vertical slit pupils helping them to judge the distance to prey in dim light. Different ambush predators use a variety of means to capture their prey, from the long sticky tongues of chameleons to the expand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sessility (motility)
Sessility is the biological property of an animal describing its lack of a means of self-locomotion. Sessile animals for which natural ''motility'' is absent are normally immobile. This is distinct from the botanical concept of sessility, which refers to an organism or biological structure attached directly by its base without a stalk. Sessile animals can move via external forces (such as water currents), but are usually permanently attached to something. Organisms such as corals lay down their own substrate from which they grow. Other organisms grow from a solid object, such as a rock, a dead tree trunk, or a human-made object such as a buoy or ship's hull. Mobility Sessile animals typically have a motile phase in their development. Sponges have a motile larval stage and become sessile at maturity. Conversely, many jellyfish develop as sessile polyps early in their life cycle. In the case of the cochineal, it is in the nymph stage (also called the crawler stage) that the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motility
Motility is the ability of an organism to move independently using metabolism, metabolic energy. This biological concept encompasses movement at various levels, from whole organisms to cells and subcellular components. Motility is observed in animals, microorganisms, and even some plant structures, playing crucial roles in activities such as foraging, reproduction, and cellular functions. It is genetically determined but can be influenced by environmental factors. In multicellular organisms, motility is facilitated by systems like the Nervous system, nervous and Human musculoskeletal system, musculoskeletal systems, while at the cellular level, it involves mechanisms such as amoeboid movement and flagellar propulsion. These cellular movements can be directed by external stimuli, a phenomenon known as taxis. Examples include chemotaxis (movement along chemical gradients) and phototaxis (movement in response to light). Motility also includes physiological processes like gastroi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aquatic Locomotion
Aquatic locomotion or swimming is biologically propulsion , propelled motion through a liquid medium. The simplest propulsive systems are composed of cilia and flagella. Swimming has evolved a number of times in a range of organisms including arthropods, fish, molluscs, amphibians, reptiles, birds, and mammals. Evolution of swimming Swimming evolved a number of times in unrelated lineages. Supposed jellyfish fossils occur in the Ediacaran, but the first free-swimming animals appear in the Early to Middle Cambrian. These are mostly related to the arthropods, and include the Anomalocarididae , Anomalocaridids, which swam by means of lateral lobes in a fashion reminiscent of today's cuttlefish. Cephalopods joined the ranks of the active swimmers (nekton) in the late Cambrian, and chordates were probably swimming from the Early Cambrian. Many terrestrial animals retain some capacity to swim, however some have returned to the water and developed the capacities for aquatic locomotio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anoxic Waters
Anoxic waters are areas of sea water, fresh water, or groundwater that are depleted of dissolved oxygen. The US Geological Survey defines anoxic groundwater as those with dissolved oxygen concentration of less than 0.5 milligrams per litre. Anoxic waters can be contrasted with hypoxic waters, which are low (but not lacking) in dissolved oxygen. Often, hypoxia is defined as waters that have less than 2 milligrams per litre of dissolved oxygen. This condition is generally found in areas that have restricted water exchange. In most cases, oxygen is prevented from reaching the deeper levels by a physical barrier, as well as by a pronounced density stratification, in which, for instance, denser, colder or hypersaline waters rest at the bottom of a basin. Anoxic conditions will occur if the rate of oxidation of organic matter by bacteria is greater than the supply of dissolved oxygen. Anoxic waters are a natural phenomenon, and have occurred throughout geological history. The Permia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pycnocline
A pycnocline is the cline or layer where the density gradient () is greatest within a body of water. An ocean current is generated by the forces such as breaking waves, temperature and salinity differences, wind, Coriolis effect, and tides caused by the gravitational pull of celestial bodies. In addition, the physical properties in a pycnocline driven by density gradients also affect the flows and vertical profiles in the ocean. These changes can be connected to the transport of heat, salt, and nutrients through the ocean, and the pycnocline diffusion controls upwelling. Below the mixed layer, a stable density gradient (or pycnocline) separates the upper and lower water, hindering vertical transport. This separation has important biological effects on the ocean and the marine living organisms. However, vertical mixing across a pycnocline is a regular phenomenon in oceans, and occurs through shear-produced turbulence. Such mixing plays a key role in the transport of nutrients. P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swim Bladder
The swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled organ (anatomy), organ in bony fish that functions to modulate buoyancy, and thus allowing the fish to stay at desired water depth without having to maintain lift (force), lift via swimming, which expends more energy. Also, the Dorsum (biology), dorsal position of the swim bladder means that the expansion of the bladder moves the center of mass downwards, allowing it to act as a stabilizing apparatus. Additionally, the swim bladder functions as a resonating chamber (anatomy), resonating chamber to produce or receive sound. The swim bladder is evolutionarily homology (biology), homologous to the lungs of tetrapods and lungfish, and some ray-finned fish such as bowfins have also evolved similar respiratory functions in their swim bladders. Charles Darwin remarked upon this in ''On the Origin of Species'', and reasoned that the lung in air-breathing vertebrates had derived from a more primitive swim b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Plan
A body plan, (), or ground plan is a set of morphology (biology), morphological phenotypic trait, features common to many members of a phylum of animals. The vertebrates share one body plan, while invertebrates have many. This term, usually applied to animals, envisages a "blueprint" encompassing aspects such as symmetry (biology), symmetry, Germ layer, layers, segmentation (biology), segmentation, nerve, Limb (anatomy), limb, and Gastrointestinal tract, gut disposition. Evolutionary developmental biology seeks to explain the origins of diverse body plans. Body plans have historically been considered to have evolved in a flash in the Ediacaran biota; filling the Cambrian explosion with the results, and a more nuanced understanding of animal evolution suggests gradual development of body plans throughout the early Palaeozoic. Recent studies in animals and plants started to investigate whether evolutionary constraints on body plan structures can explain the presence of development ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
