What do phylum chordata have in common

A comparison of the genomes of a lancelet, tunicate, lamprey, fish, chicken, and human confirmed that two whole-genome duplications occurred in the early history of the Vertebrata subphylum. Both fossil and genomic evidence suggests that vertebrates arose during the Cambrian explosion. The Cambrian explosion was the relatively brief span of time during the Cambrian period during which many animal groups appeared and rapidly diversified.

Most modern animal phyla originated during the Cambrian explosion. Vertebrates are members of the subphylum Vertebrata, under the phylum Chordata and under the kingdom Animalia. Animals that possess bilateral symmetry can be divided into two groups, protostomes and deuterostomes, based on their patterns of embryonic development. Echinoderms are invertebrate marine animals that have pentaradial symmetry and a spiny body covering; the phylum includes sea stars, sea urchins, and sea cucumbers.

The phylum Chordata contains two groups of invertebrate chordates, but the most conspicuous and familiar members of Chordata are the vertebrates. Phylum chordata : All chordates are deuterostomes, possessing a notochord. Vertebrates are differentiated by having a vertebral column. As chordates, all vertebrates have a similar anatomy and morphology with the same qualifying characteristics: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail.

However, the subphylum Vertebrata is distinguished from the phylum Chordata by the development of the notochord into a bony backbone. Vertebrates include the amphibians, reptiles, mammals, and birds, as well as the jawless fishes, bony fishes, sharks, and rays. Diversity of vertebrates: animals with backbones : The subphylum Vertebrata contains all animals that possess backbones, gills, and a central nervous system in at least one phase of development.

Vertebrates include amphibians, reptiles, mammals, and birds, as well as the jawless fishes, bony fishes, sharks, and rays. More than 64, species of vertebrates have been described, but the extant vertebrate species represent only a small portion of all the vertebrates that have existed. Vertebrates range in size from the frog species Paedophryne amauensis as small as 7. Vertebrates comprise about 4 percent of all described animal species; the remainder are invertebrates, which lack backbones.

All vertebrates are built along the basic chordate body plan: a stiff rod running through the length of the animal vertebral column , with a hollow tube of nervous tissue the spinal cord above it and the gastrointestinal tract below. In all vertebrates, there is a mouth at anterior end of the animal and an anus before the posterior end of the body. Vertebrates are defined by the presence of the vertebral column. In vertebrates, the notochord develops into the vertebral column or spine: a series of bony vertebrae each separated by mobile discs.

These vertebrae are always found on the dorsal side of the animal. However, a few vertebrates have secondarily lost their vertebrae and, instead, retain the notochord into adulthood e. Vertebral column : A fossilized skeleton of the dinosaur Diplodocus carnegii shows an extreme example of the backbone that characterizes vertebrates.

Vertebrates are also the only members of Chordata to possess a brain. In chordates, the central nervous system is based on a hollow nerve tube that runs dorsal to the notochord along the length of the animal.

In vertebrates, the anterior end of the nerve tube expands and differentiates into three brain vesicles. Vertebrates are the largest group of chordates, with more than 62, living species.

Vertebrates are grouped based on anatomical and physiological traits. Tetrapods can be further divided into two groups: amphibians and amniotes. Amniotes are animals whose eggs are adapted for terrestrial living; this group includes mammals, reptiles, and birds.

Amniotic embryos, developing in either an externally-shelled egg or an egg carried by the female, are provided with a water-retaining environment and are protected by amniotic membranes. Privacy Policy. Skip to main content. Search for:. Characteristics of Chordata Animals in the phylum Chordata share four key features: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail.

Learning Objectives Identify the key features of the chordates. Key Takeaways Key Points These characteristics are only present during embryonic development in some chordates. The notochord provides skeletal support, gives the phylum its name, and develops into the vertebral column in vertebrates. The dorsal hollow nerve cord develops into the central nervous system: the brain and spine.

Pharyngeal slits are openings in the pharynx that develop into gill arches in bony fish and into the jaw and inner ear in terrestrial animals.

The post-anal tail is a skeletal extension of the posterior end of the body, being absent in humans and apes, although present during embryonic development. Key Terms notochord : a flexible rodlike structure that forms the main support of the body in the lowest chordates; a primitive spine nerve cord : a dorsal tubular cord of nervous tissue above the notochord of a chordate pharyngeal slit : filter-feeding organs found in non-vertebrate chordates lancelets and tunicates and hemichordates living in aquatic environments.

In vertebrates this becomes the spinal cord and brain. Pharyngeal Slits and Pharyngeal Arches Phyngeal slits are filter-feeding organs found in the non-vetebrate chordates. Endostyle The endostyle is a longitudinal ciliated groove on the ventral surface of the pharynx that produces mucus to gather food particles.

Post-anal Tail Basically, chordates have a muscular tail that extends back, past the anus. Classification The following living classes exist in the phylum Chordata referencing www.

Eastern Rat Snake P. Blue Shark Prionace glauca. Gopher Tortoise Gopherus polyphemus. Hellbender Cryptobranchus alleganiensis. Coral Catshark Atelomycterus marmoratus. Caribbean Reef Shark Carcharhinus perezi. Salmon Shark Lamna ditropis. Pacific Sleeper Shark Somniosus pacificus. School Shark Galeorhinus galeus. Leopard Shark Triakis semifasciata. Common Name: Chordates. Classification Kingdom:. Science Newsletter:. Full List of our Videos. Teaching Biology? How to Make Science Films.

Read our Wildlife Guide. On the Trail of the Egret. Tips for Shooting Smoke Grenade Photos. Pacific Sleeper Shark: Giant of the Deep. The Burmese Python - A docile ish giant. Australia's Most Dangerous Creatures. White-nosed Syndrome in Bats. Gluten and You. Arctic Tundra Biome. The Science of Breadmaking.

How does water move in plants? What is the molecular clock? Plants Can Make Memories. Recall that animals that possess bilateral symmetry can be divided into two groups—protostomes and deuterostomes—based on their patterns of embryonic development. Echinoderms are invertebrate marine animals that have pentaradial symmetry and a spiny body covering, a group that includes sea stars, sea urchins, and sea cucumbers.

The most conspicuous and familiar members of Chordata are vertebrates, but this phylum also includes two groups of invertebrate chordates. In some groups, some of these key chacteristics are present only during embryonic development.

The chordates are named for the notochord , which is a flexible, rod-shaped mesodermal structure that is found in the embryonic stage of all chordates and in the adult stage of some chordate species.

It is strengthened with glycoproteins similar to cartilage and covered with a collagenous sheath. The notocord is located between the digestive tube and the nerve cord, and provides rigid skeletal support as well as a flexible location for attachment of axial muscles. However, in vertebrates craniates , the notochord is present only during embryonic development, at which time it induces the development of the neural tube and serves as a support for the developing embryonic body.

The notochord, however, is not found in the postembryonic stages of vertebrates; at this point, it has been replaced by the vertebral column that is, the spine. Which of the following statements about common features of chordates is true?

In chordates, it is located dorsally to the notochord. In vertebrates, the neural tube develops into the brain and spinal cord, which together comprise the central nervous system CNS. The peripheral nervous system PNS refers to the peripheral nerves including the cranial nerves lying outside of the brain and spinal cord. Pharyngeal slits are openings in the pharynx the region just posterior to the mouth that extend to the outside environment.

In organisms that live in aquatic environments, pharyngeal slits allow for the exit of water that enters the mouth during feeding. Some invertebrate chordates use the pharyngeal slits to filter food out of the water that enters the mouth.

The endostyle is a strip of ciliated mucus-producing tissue in the floor of the pharynx. Food particles trapped in the mucus are moved along the endostyle toward the gut.

The endostyle also produces substances similar to thyroid hormones and is homologous with the thyroid gland in vertebrates. In vertebrate fishes, the pharyngeal slits are modified into gill supports, and in jawed fishes, into jaw supports.

In tetrapods land vertebrates , the slits are highly modified into components of the ear, and tonsils and thymus glands. In other vertebrates, pharyngeal arches, derived from all three germ layers, give rise to the oral jaw from the first pharyngeal arch, with the second arch becoming the hyoid and jaw support. The post-anal tail is a posterior elongation of the body, extending beyond the anus.

The tail contains skeletal elements and muscles, which provide a source of locomotion in aquatic species, such as fishes. In some terrestrial vertebrates, the tail also helps with balance, courting, and signaling when danger is near. Click for a video discussing the evolution of chordates and five characteristics that they share. Two clades of chordates are invertebrates: Cephalochordata and Urochordata.

Members of these groups also possess the five distinctive features of chordates at some point during their development. The notochord extends into the head, which gives the subphylum its name. Although the neural tube also extends into the head region, there is no well-defined brain, and the nervous system is centered around a hollow nerve cord lying above the notochord.

Extinct members of this subphylum include Pikaia , which is the oldest known cephalochordate. Excellently preserved Pikaia fossils were recovered from the Burgess shales of Canada and date to the middle of the Cambrian age, making them more than million years old. Its anatomy of Pikaia closely resembles that of the extant lancelet in the genus Branchiostoma. The lancelets are named for their bladelike shape.

Lancelets are only a few centimeters long and are usually found buried in sand at the bottom of warm temperate and tropical seas. Cephalochordates are suspension feeders. A water current is created by cilia in the mouth, and is filtered through oral tentacles. Water from the mouth then enters the pharyngeal slits, which filter out food particles.

The filtered water collects in a gill chamber called the atrium and exits through the atriopore. Trapped food particles are caught in a stream of mucus produced by the endostyle in a ventral ciliated fold or groove of the pharynx and carried to the gut. Most gas exchange occurs across the body surface.