Fish Classification Types
by Owen Borville
March 4, 2021
Biology, Learning, Science
Fishes are mainly divided into jawless, cartilaginous, and bony types.
Jawless fishes (Agnatha) include the hagfish and lampreys. These have long cylindrical bodies and a cartilaginous skeleton. The agnatha appeared in Cambrian strata, along with many other forms of life. The hagfish and lampreys are the only types of jawless fish that have not been extinct. Agnatha are carniverous. Jawless fish do not have jaws, no paired fins, no scales, no bones, or stomachs. Jawless fish do feature a cartilage skeleton, notochord, paired gill pouches, a pineal eye, and a two chambered heart, along with a rounded mouth with teeth and a tongue.
Jawless fish are described as "primitive" and the "ancestor" of jawed fishes by evolutionist scientists, but creationists describe these as a unique creation that do not fit on an evolutionary line. Jawless fish are simply different than other fishes and should be classified as a unique kind. Jawless fish have a unique circular mouth along with long, cylindrical bodies almost snake-like, making these uniquely different than other fishes and other animals. The notochord is described as a "primitive backbone," a flexible rod-like structure that supports the body, but serves a similar purpose as vertebrae and spinal chords. A creation advocate could argue that the notochord serves the needs of the jawless fish better than vertebrae and that it was given what it needed to function in its environment. The cartilage skeleton of jawless fish is firm but flexible allowing for distinctive movement in the waters.
Cartilaginous fishes, chondrichthyes, include the sharks, skates, and sting rays. Skates and rays are similar, but skates have a shorter tail and don't sting. Cartilaginous fishes feature cartilage skeletons instead of bone, paired fins, paired nostrils, scales, two-chambered hearts. Cartilaginous fishes are mostly marine fishes and have gills.
The bony fishes, osteichthyes, are divided into the ray-finned fish and the lobe-finned fish. Bony fish are characterized by their calcified bony skeleton with vertebrae, hinged jaws and gills. Bony fish can be both freshwater or marine. Both bony and cartilaginous fishes have a lateral line organ that enables detection of movement or vibrations in the water. Bony fishes have scales, paired fins, and paired nostrils. Swim bladders help control buoyancy.
All fishes are cold-blooded, live in water, and use gills to breathe, have swim bladders, and fins for swimming. Fish have all five senses that humans have, plus the lateral line sixth sense.
Some fishes have unique abilities, such as the ability of the peacock flounder to disguise itself in the sand, defense mechanisms such as facial spikes in clown loaches, tigerfish catch birds in the air, archerfish squirt prey in the air, electroreception in the sawfish detect prey, salmon magnetic field navigation, hagfish slime defense mechanisms, Antarctic tooth fish or polar fish antifreeze blood, gobies climb rocks upward with their mouths and bodies, black swallowers with large stomachs eat large amounts at once, plain fin midshipmen hum to attract mates, pirate perch chemical camouflage, and mudskippers climb trees and move on land.
There is no primitive animal and no evolutionary line-Every animal and living thing is complex and a product of a Creative Designer.
by Owen Borville
March 4, 2021
Biology, Learning, Science
Fishes are mainly divided into jawless, cartilaginous, and bony types.
Jawless fishes (Agnatha) include the hagfish and lampreys. These have long cylindrical bodies and a cartilaginous skeleton. The agnatha appeared in Cambrian strata, along with many other forms of life. The hagfish and lampreys are the only types of jawless fish that have not been extinct. Agnatha are carniverous. Jawless fish do not have jaws, no paired fins, no scales, no bones, or stomachs. Jawless fish do feature a cartilage skeleton, notochord, paired gill pouches, a pineal eye, and a two chambered heart, along with a rounded mouth with teeth and a tongue.
Jawless fish are described as "primitive" and the "ancestor" of jawed fishes by evolutionist scientists, but creationists describe these as a unique creation that do not fit on an evolutionary line. Jawless fish are simply different than other fishes and should be classified as a unique kind. Jawless fish have a unique circular mouth along with long, cylindrical bodies almost snake-like, making these uniquely different than other fishes and other animals. The notochord is described as a "primitive backbone," a flexible rod-like structure that supports the body, but serves a similar purpose as vertebrae and spinal chords. A creation advocate could argue that the notochord serves the needs of the jawless fish better than vertebrae and that it was given what it needed to function in its environment. The cartilage skeleton of jawless fish is firm but flexible allowing for distinctive movement in the waters.
Cartilaginous fishes, chondrichthyes, include the sharks, skates, and sting rays. Skates and rays are similar, but skates have a shorter tail and don't sting. Cartilaginous fishes feature cartilage skeletons instead of bone, paired fins, paired nostrils, scales, two-chambered hearts. Cartilaginous fishes are mostly marine fishes and have gills.
The bony fishes, osteichthyes, are divided into the ray-finned fish and the lobe-finned fish. Bony fish are characterized by their calcified bony skeleton with vertebrae, hinged jaws and gills. Bony fish can be both freshwater or marine. Both bony and cartilaginous fishes have a lateral line organ that enables detection of movement or vibrations in the water. Bony fishes have scales, paired fins, and paired nostrils. Swim bladders help control buoyancy.
All fishes are cold-blooded, live in water, and use gills to breathe, have swim bladders, and fins for swimming. Fish have all five senses that humans have, plus the lateral line sixth sense.
Some fishes have unique abilities, such as the ability of the peacock flounder to disguise itself in the sand, defense mechanisms such as facial spikes in clown loaches, tigerfish catch birds in the air, archerfish squirt prey in the air, electroreception in the sawfish detect prey, salmon magnetic field navigation, hagfish slime defense mechanisms, Antarctic tooth fish or polar fish antifreeze blood, gobies climb rocks upward with their mouths and bodies, black swallowers with large stomachs eat large amounts at once, plain fin midshipmen hum to attract mates, pirate perch chemical camouflage, and mudskippers climb trees and move on land.
There is no primitive animal and no evolutionary line-Every animal and living thing is complex and a product of a Creative Designer.