Vertebrates
Vertebrates are: According to the definition,
"vertebrates are animals that have a vertebral column and notochord at any
time in their lives."
One way to define life is by whether or not vertebrates are
present. It is believed that vertebrates and invertebrates shared a common
ancestor that existed approximately 600 million years ago.
Vertebrates have branched out into a long lineage that
includes woolly mammoths, armored fish, and enormous sauropods since true
vertebrates appeared 525 million years ago.
Characteristics of Vertebrates A vertebrate is an animal
that has all of the following characteristics at some point in its life:
• A rigid rod that runs the length of the animal; it could
be the notochord or the vertebral column. When they are embryos, humans and all
other vertebrates have a notochord that develops into the vertebral column.
• A network of nerves extends above the alimentary canal
beneath the vertebral column.
• The mouth of the animal can be found just below or at the
animal's front.
• The alimentary canal terminates at the anus, which opens
to the outside. The tail comes after the anus.
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Vertebrates are categorized into seven groups according to their anatomical and physiological characteristics. They are:
Mammals (Class Mammalia) can maintain a constant body
temperature regardless of the outside temperature. Endothermic animals, which
include humans and platypuses, are a result of this.
Birds (Class Aves) From a biological perspective, birds,
more commonly referred to as avian dinosaurs, are comparable to dinosaurs. Feathers,
beaks without teeth, and a fast metabolic rate set this group of species apart
from others. In addition, members of the class Aves produce hard-shelled eggs.
The reptile family (class Reptilia) includes tetrapod
reptiles like snakes, crocodiles, tuataras, and turtles. Reptiles are
distinguished by their ectothermic behavior. Snakes remain tetrapods despite
having no discernible limbs. This is because snakes come from limb-bearing
ancestors.
Amphibians (Class Amphibia) Salamanders, frogs, and toads
are examples of amphibians, which are ectothermic tetrapods. How reptiles and
amphibians reproduce sets them apart from one another. The majority of
amphibians can only produce in water because their eggs lack a shell. In
addition, they go through a process known as metamorphosis, during which the
larvae transform into terrestrial adults with gills and fins.
Hard fishes (Class Osteichthyes) are distinguished by the
fact that their skeleton is largely composed of bone rather than a ligament, as
is the case with sharks. The osteocheichthyes group of vertebrates is also the
most extensive currently.
As the name suggests, cartilaginous fishes (Class
Chondrichthyes) have a skeleton made of cartilage. Its members include sawfish,
skates, sharks, rays, and others. One example of a shark that can live for
several centuries is the massive Greenland shark. It was discovered that a
specimen tagged in 2016 was at least 273 years old.
According to fossil records, jawless fishes (Class Agnatha)
are extremely primitive fishes that have not changed much over millions of
years. They eat other fish by holding onto them with rows of tiny, sharp teeth
in their circular mouths, which have no jaws. The majority of these creatures
are parasites and scavengers.
Questions Frequently Asked
1. What kinds of vertebrates do
we have?
Those animals that have a spine are called vertebrates.
There are numerous living vertebrates, which are classified into seven groups
based on their physiological and anatomical characteristics.
2. What does the term "vertebrate" mean?
Vertebrates and invertebrates may have come from the same
ancestor many millions of years ago. However, according to evolutionary theory,
vertebrates are currently thought to be the most advanced forms of life on
Earth. In the natural world, they have a significant advantage over
invertebrates because of their intricate anatomy and physiology.
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3. Which seven vertebrate families are there?
Based on their anatomical and physiological characteristics,
seven groups of vertebrates have been identified. The main ones are as follows:
• Class Aves
• Class Reptilia
• Class Agnatha
• Class Mammalia
• Class Osteichthyes
• Class Chondrichthyes
4 . Which vertebrates make
amniotic eggs?
Birds and reptiles typically lay amniotic eggs. Mammals also
produce amniotic eggs, despite their specialization in internal development.
However, some modern mammals continue to do so, as their ancestors did.
5. When were the first vertebrates found?
The first vertebrates are thought to have evolved 525
million years ago. It is believed that Myllokunmingia was the very first
vertebrate. On the other hand, additional evidence suggests that Pikaia gracile
was the very first vertebrate and the ancestor of all vertebrates currently in
existence.