Ray-finned fishes are the dominant aquatic vertebrates today
, making up about half of all vertebrate species known. They are found in every aquatic habitat from the abyssal depths of the ocean to freshwater streams and ponds; a few can even crawl on land for short periods of time.
What are the 4 main characteristics of a ray-finned fish?
The anatomy of ray-finned fish shows many of the characteristics common to all chordates:
pharyngeal slits, a nerve cord, and body wall muscles arranged in myotomes, or segmented blocks
. Ray-finned fish also have several unique anatomical features that suggest adaptation for an aquatic lifestyle.
What phylum is Actinopterygii?
Chordate
What is the difference between lobe and ray-finned fish?
The ray-finned fish have fin rays, with fins supported by bony spines known as rays.
The lobe-finned fish are characterized by fleshy lobed fins, as opposed to the bony fins of the ray-finned fish
.
Are ray-finned fish tetrapods?
Tetrapods evolved from a finned organism that lived in the water. However, this ancestor was not like most of the fish we are familiar with today.
Most animals we call fishes today are ray-finned fishes
, the group nearest the root of this evogram.
Do ray-finned fish have bony skeletons?
The skeleton of the paired fins is formed from many small bones, called fin rays
, in a fan-like arrangement, which are supported at the bases of the fins by parallel rows of bones called radials.
Do ray-finned fish have hair?
They have a bony endoskeleton with a backbone and jaws; they breathe only with lungs; they have four limbs;
their skin is covered with hair or fur
; they have amniotic eggs; they have mammary (milk-producing) glands; they are endothermic.
What sets vertebrates apart from other chordates?
Vertebrates make up the majority of chordates. They have many traits that set them apart from other chordates, including
the backbone, a segmented column of bones known as vertebrae that surrounds and protects the spinal cord. They also have a well-developed head protected by a skull
.
Are ray-finned fish ectothermic or endothermic?
Ray-Finned Fish
They have a backbone and jaws; their endoskeleton is made of bones; they have thin, bony fins;
they are ectothermic
.
Are ray-finned fish carnivores?
Some species are planktonic feeders, however
most are carnivores
, feeding on other fish and crustaceans and have well developed canine-like teeth.
Why are ray-finned fish so diverse?
It was thought that
the genome duplication might accelerate the rate at which the group could modify existing traits and evolve new features, giving them access to new environments or lifestyles
. In other words, there was something inherently special about teleosts that gave them remarkable abilities to diversify.
What is the difference between Actinopterygii and Sarcopterygii?
The key difference between sarcopterygii and actinopterygii relies mainly on their fin structure.
Sarcopterygii fish species have lobed fins, while the actinopterygii fish species have ray fins
. Moreover, the rate of extinction in sarcopterygii is higher in comparison to actinopterygii.
Are perch ray-finned or lobe-finned fish?
There are three groups of the bony fish — ray-finned fish, lobe-finned fish, and the lung fish. The perch is an example of a
ray-finned fish
. Its fins have spiny rays of cartilage &/or bone to support them. Fins help the perch to move quickly through the water and steer without rolling.
Is an eel a teleost fish?
eel, (order Anguilliformes),
any of more than 800 species of teleost fishes
characterized by elongate wormlike bodies. Anguilliforms include the common freshwater eels as well as the voracious marine morays.
What are the characteristics of lobe-finned fishes?
One of the most important characteristics of lobe-finned fish is the
lobe in their fins
. Unlike other fish, sarcopterygian fish has a cental appendage in their fins containing many bones and muscles. The fins are very flexible and potentially useful for supporting the body on land, as in lungfish and tetrapods.
Why are amphibians reptiles Aves and mammals called tetrapods?
Answer: Tetrapods can be defined in cladistics as
the nearest common ancestor of all living amphibians the lissamphibians and all living amniotes reptiles, birds, and mammals along with all of the descendants of that ancestor
. The group so defined is known as the tetrapod total group.
Did tetrapods evolved from fish?
Tetrapods evolved from a group of animals known as the Tetrapodomorpha which, in turn, evolved from ancient sarcopterygian fish around 390 million years ago in the middle Devonian period
; their forms were transitional between lobe-finned fishes and the four-limbed tetrapods.
Do ray-finned fish have paired fins?
Ray-finned fish have a true vertebral column (or backbone),
paired fins
, and scales. So what exactly is a “ray-fin?” Ray fins consist of webs of skin tissue supported by flexible, bony rays or spines. These fins are not muscularized, so their movements are dictated by body muscles.
Do amphibians have bony skeletons?
Mammals, birds, reptiles, amphibians and fish have bony skeletons
. These skeletons come in all shapes and sizes, but they also share common features.
Do ray-finned fish have an Operculum?
They do not have fin spines, but instead support the fin with lepidotrichia (bone fin rays).
They also have an operculum
, which helps them breathe without having to swim.
Which fish does not have skeleton made of bone?
Sharks, skates, rays and chimaeras
stand apart from other jawed vertebrates in having a skeleton that is made primarily of cartilage rather than bone.
Which characteristic is common to all chordates?
What is it? Chordates, including humans, all have four common evolutionary characteristics-
a dorsal nerve cord
, a notochord, pharyngeal gill slits, and a post-anal tail.
Are lampreys bony or cartilaginous?
Lampreys are in the clade Petromyzontidae and appear morphologically similar to hagfish, but contain
cartilaginous vertebral elements as an adult
; thus, they are considered true vertebrates.
Are amphibians endothermic or ectothermic?
Reptiles and amphibians are
ectotherms
, while birds are endotherms. An ectotherm (reptile/amphibian) relies primarily on its external environment to regulate the temperature of its body. Endotherms (birds) are able to regulate their body temperatures by producing heat within the body.
