Puffer fish, also called blowfish, are found in tropical marine and brackish water. These strange-looking creatures are very clumsy swimmers that can quickly inflate themselves to become a mass several times their original size in order to defend against predators.
When threatened, pufferfish inflate by swallowing water and air, which erects spines on their bodies. These spines are composed of nanocrystalline hydroxypatite, protein (collagen), and water.
Vertebrae
The vertebrae, which are part of the skeleton in fish, are important for support and strength. They are made of either cartilage (cartilaginous fish) or bone (bony fish). The skeletal structure is important because it helps to support the muscles that are inside the animal. It also helps to protect the spinal cord and nerves that are located in the spinal column.
Vertebrae can be grouped into two types: cervical and thoracic. The cervical vertebrae are found in the neck and are responsible for supporting the weight of the head, while the thoracic vertebrae are located in the back and are responsible for protecting the heart and lungs.
Puffer fish (family Tetraodontidae) have a skeleton that is composed of several different kinds of vertebrae. The vertebrae in this group are a combination of cartilage and bone, which makes them very strong and lightweight.
One type of vertebra is the ring-shaped atlas vertebra. It is a very special type of vertebra that serves as a pillar for the body. Another type of vertebra is the peg-shaped axis.
This type of vertebra is very similar to the spine of an octopus, but it has a slightly more complex shape. The axis is formed by the vertebrae of a puffer fish, which are arranged in pairs.
The skeleton of the vertebrae is a very crucial component in the survival and development of a fish. It provides a foundation for the muscles that help to move and control the animal.
However, the skeleton can also be damaged by physical trauma. This can result in a number of health problems, including spinal cord damage and paralysis.
In order to prevent these injuries, it is vital that the vertebrae are strong and durable. This can be achieved by increasing the thickness of the bones in the vertebrae.
To do this, scientists will have to test the skeletons of many different species of fish. This will allow researchers to compare the properties of different types of bones and see how they affect the body of a fish.
The skeleton of a puffer fish is extremely important, as it helps the fish to stay healthy and strong. It also helps to protect the body from injury and allows the fish to move more easily.
Ribs
Ribs are paired bones that form the thoracic cage and protect the heart and lungs. They articulate with the vertebral column posteriorly and terminate anteriorly as cartilage (costal cartilage).
The ribs are found in all mammals, birds, reptiles, and fish. They are part of the bony thorax and are essential for movement; they move during expansion to allow the lung to inflate.
A typical rib has a wedge-shaped head on the posterior end, which articulates with the numerically corresponding vertebra via two articular facets. A rounded neck connects the head to the body of the rib, where a tubercle is present. The tubercle also articulates with the transverse process of the thoracic vertebra in which the rib is attached.
This area contains grooves that allow for the passage of subclavian vessels, which are needed to transport blood from the arms to the thorax. The rib is usually quite short and wide, but it can be longer and thinner as well.
Each rib also has a roughened area on its upper surface, where the scalene muscle originates from. The rib articulates with the first thoracic vertebra.
The ribs are also known for their spines, which consist of nanocrystalline hydroxyapatite and protein. These spines are very sharp and can pierce predators when the pufferfish is inflated.
Scientists believe that these spines evolved in puffers as anti-predator defense, just like their inflation behavior. It seems that the spiky spines must have been an evolutionary adaptation, as their close triggerfish relatives lack them.
Inflating the pufferfish’s body also allows it to swallow water more rapidly. This helps it fend off predators and prevents them from eating its food.
Pufferfish eat a variety of invertebrates, including clams, oysters, sea urchins, crabs and shrimp. They grow to one foot in length and live in shallow waters, usually near shores.
They are diurnal, which means they only move at night. They have no pectoral fins and are incredibly light and flexible when compared with other fish of their size. They are also extremely fast-acting, which is why they can slurp up so much water and air.
Pelvic Fins
The pelvic fins of a puffer fish skeleton are paired and situated on the midline of the body. These are a common feature of perciform (fish with spiny rays) skeletons; they allow these fish to maneuver more easily over short distances than their pectoral fins.
The pelvic fin is a three-part structure composed of a propterygium, mesopterygium and metapterygium, similar to the structure in sharks and rays. The propterygium and mesopterygium are used for flight and the metapterygium is used for swimming.
Pelvic fins are important for the limb-to-fin transition, which occurs in the earliest fish-to-tetrapods (Clack, 2000). The earliest fossils in this transition have not yet been found, but the evidence suggests that the transition occurred in a very brief period of time between Panderichthys and Acanthostega (Coates, 1996; Coates & Cohn, 1998).
There is evidence that the pelvic fin/hindlimb type specification was established earlier than previously thought, although it is not clear how this is accomplished. A number of genes are involved in the establishment of hindlimb/pelvic fin identity (Gibson-Brown et al. 1996; Tamura et al. 1999; Ruvinsky et al. 2000).
In the early stages of limb development, Hox gene expression is collinear across forelimbs and hindlimbs, whereas it is not expressed at the same frequency in a forelimb-to-hindlimb transition. This expression pattern is referred to as ‘pelvic before pectoral’.
This is because a key developmental stage during limb development involves the migration of cells from the interlimb region to the pelvic fin field. This process is facilitated by the repositioning of the trunk-tail during development, which allows for the extension of posterior expression boundaries for the Hox genes (Lance-Jones et al. 2001; Choe et al. 2006).
Furthermore, a number of recent studies have shown that this pattern of collinear expression is conserved in cartilaginous fish (Chondrichthyes), but is not observed in tetrapods and teleosts. In addition, Shh expression is only seen in later stages of post-budding development and the expression domain does not map to the zone of potential anatomical position (ZPA) of the developing pelvic fins.
The repositioning of the trunk-tail and its subsequent recruitment of the pelvic fin precursor cells to the pelvic fin field is a critical mechanism for the evolution of the paired hindlimb/pelvic fin in vertebrates. It is proposed that a conserved Hox gene, Hoxc10, is required for this induction. During hindlimb/pelvic fin positioning, the embryo’s trunk-tail protrudes and repositions the Hoxc10 expression domain to the pelvic fin field.
Spines
The spines of a puffer fish skeleton are important in protecting the fish’s skin and preventing injury. Spines also help the fish expand its body size when it’s inflated by taking in water or air, as well as protecting it from predators who might try to bite it when it’s not fully inflated.
The vertebrae of a puffer fish skeleton have a variety of different shapes and sizes, depending on how heavy the animal is and what its habitat is like. Some species of fish, such as tuna and salmon, have backbones that are very thick, while others, like carp and goldfish, have thin bones.
When scientists looked at the skeleton of the three-tooth pufferfish (Takifugu niphobles), they discovered that the fish has many different types of spines. Some of these spines stick out when the pufferfish is inflated, while other spines sit flat against the body at all other times.
According to the researchers, this variation in morphology is probably related to how the genes that control these scales and spines work. For example, the team found that a gene called fst is responsible for helping pufferfish develop their spines.
Normally, pufferfish’s spines only appear in certain places on the fish to protect them from predators. But by blocking some classic markers of skin appendage development, the researchers were able to reduce how many spines appeared on the pufferfish and make them sprout in more varied areas around its body.
In the future, the researchers hope to find out what factors allowed for the diversity in spine coverage and morphology. They plan to sequence the genetic code of the various pufferfish species and see what differences they have from each other, as well as how those differences relate to their morphology.
The research is important because it’s the first to identify how a pufferfish gets its spines. The researchers say the spines evolved through a process similar to how hair or feathers get their characteristics.
Pufferfish are able to grow their body size by ingesting large amounts of water or air and inflating themselves when threatened. This ability to inflate helps them protect themselves from predators and makes them much less palatable to animals that might want to eat them.