Not quite a reptile, not quite a fish, but not quite a mammal. Amphibians are one of the most unique, yet most commonly sighted organisms on Earth. Although they thrive in both land and water, they are often more vulnerable than marine or terrestrial animals. What are the main characteristics of Amphibians, and why are they the most varied living species? Keep on reading to find out more about these adaptive creatures.

What Are Amphibians?

In layman’s term, Amphibians are any species of frogs, toads, salamanders, and newts that you see. However, each animal in this group only shares several common characteristics, unlike other species like humans and other mammals.

Amphibians are animal species that belong to the Class Amphibia. This specie is said to be 370 million years old and has been divided into more than 7,000 species globally. The origin of the first Amphibian is said to be from a sarcopterygian fish, which developed lungs and bony-limbed fins.

As of now, modern Amphibians belong to a group called Lissamphibia. Although not all species under this group have a lot of similarities, there are ten things that they have in common as a part of the subclass. These characteristics are further elaborated below.

Classification of Amphibians and their characteristics

1. Amphibians are divided into three classification

The modern classification of Amphibians is used to separate them from extinct species and to make identification easier. Although 90% of the existing species of Amphibians right now are frogs, there are two other classifications that house the 10%.

  • Anura – The Anura classification includes all the species of frogs. Anura came from the Ancient Greek word that means “without a tail.” Therefore, it suggests the stage of adult frogs losing their tails after childhood. Different species of Anura can be found in tropical and subarctic regions, but the majority can be found in tropical rainforests.
  • Apoda – The Apoda classification, on the other hand, houses species called Caecilians, or serpentine Amphibians that cannot see. These species often leave underground and often eat earthworms.
  • Urodela – The Urodela classification is where the lizard-like Amphibians such as salamander and newts are classified. They are usually found in Northern Hemisphere in zones called Holarctic ecozone and neotropical zone.

2. Fertilization takes place outside the body

Amphibians reproduce by laying eggs and hatching as larvae before going to metamorphosis. They usually stay in a body of water until their adulthood, where they became similar to their parents in appearance. Even if they reproduce sexually, the majority of embryonic development happens outside the body. This is the reason why some tadpoles have different body characteristics (like teeth, fins, or whisker-like skin extension) because development is subject to environmental circumstances.

3. Amphibians are cold-blooded animals

This characteristic doesn’t mean Amphibians have colder blood than mammals or other warm animals. Cold-blooded animals depend on their surroundings to generate body heat because they don’t have an internal source. That’s why the state of the environment is a big factor if they survive or not.

4. Their skin has a lot of functions

Unlike mammals, the skin of Amphibians are often thin and permeating, and that’s for good reasons. Some species use skin glands for protein production, as well as water and gas transportation. Some species fights off bacteria and fungi infection using their skin. Poisonous Amphibians use their skins as a sort of defense against predators.

5. Most Amphibians swallow their food

Here’s a thing about Amphibians: most of them are predators. Although not as scary-looking compared to other predators in water and land, Amphibians feed on insects, earthworms, and others. Bigger Amphibians would also feed on bigger mammals. These carnivorous animals tend to swallow their prey using whip-like tongues or by other means.

6. Amphibians divide their time on land and water

Amphibians divide their time on both land and water due to their body development. During their earlier stage, development of organs and body parts happen in water. After undergoing a metamorphosis, they can be seen on land to gather prey or to increase their internal temperature.

7. Young Amphibians cannot live in the sea

Although most Amphibians grow up in a body of water, this body of water is not a sea or an ocean. Some frogs can live on brackish water (seawater with lesser salinity), which can be found in mangroves, but these species are the exception rather than the rule.

8. Amphibians undergo a process called metamorphosis

Before Amphibians can get out of the water, they need to develop their lungs, skins, and other body parts to survive. The young Amphibians will grow limbs when the right environmental factors are met for their development. Once the metamorphosis is completed, they can both breath air both in water and inland.

9. Amphibians have unshelled eggs

One of the reasons why Amphibians lay an egg in water is because of the lack of a calcified shell to protect the embryo. They don’t “hatch” like terrestrial animals, which breaks the egg upon hatching. Instead, they undergo metamorphosis and continual development until they are adults.

10. Amphibian species change based on the environment

Almost all Amphibian species have very few similarities to each other, even among the species within the same subclassification. For example, all the frogs in the Anura Classification are almost similar in physical attributes. However, these frogs have different sizes, colors, and even defense mechanisms depending on the environment they live in.

What are 5 characteristics of amphibians?

Five Characteristics of Amphibians
  • Unshelled Eggs. Living amphibians produce much different eggs than strictly terrestrial organisms like reptiles do.
  • Permeable Skin. While caecilians have scales similar to fish, most other amphibians have moist, permeable skin.
  • Carnivorous Adults.
  • Distribution.
  • Courtship Rituals.

What are the 7 main characteristics of amphibians?

The 7 Amphibian Characteristics – Listed
  • External egg fertilization. When it comes to reproduction, amphibians don’t require mating before they release clear eggs with a jelly-like texture.
  • Grows 4 legs as an adult.
  • Cold-blooded.
  • Carnivorous appetite.
  • Primitive lungs.
  • Lives on water and land.
  • Vertebrates.

What are the six common characteristics of amphibians?

Terms in this set (6)
  • Endoskeleton made mostly of bone.
  • skin is smooth with many capillaries and pigments, no scales.
  • usually two pairs of limbs with webbed feet.
  • as many as four organs of respiration.
  • a three chambered heart.
  • Oviparious with external fertilization.

What are the major characteristics of amphibians?

Defining characteristics of these creatures include moist, scaleless skin and the fact that they are cold-blooded. Amphibians absorb water and undergo gas exchange through their skin. There are three orders of amphibians. Urodeles have legs and a tail, such as salamanders.

What is unique about amphibians?

Amphibians are small vertebrates that need water, or a moist environment, to survive. The species in this group include frogs, toads, salamanders, and newts. All can breathe and absorb water through their very thin skin. Another special feature of most amphibians is their egg-larva-adult life cycle.

What characteristics distinguish reptiles from amphibians?

Reptiles have scales, and their skin is dry. Amphibians do not, and their skin is often moist with mucus, which keeps them from drying up.

What are the similarities between reptiles and amphibians?

One of the similarities between reptiles and amphibians is that they are both ectotherms, which means they rely on their environment to control their body temperature. Another similarity is that many, not all, are omnivores or insectivores.

Is an amphibian a reptile?

Reptiles include snakes, turtles and lizards, while amphibians include toads, frogs and salamanders, according to Mass Audubon. Frogs are amphibians. They spend time on land, but in their larval stage, as tadpoles, they live in water. Snakes, on the other hand, are reptiles.

What are reptiles similarities and differences?

Difference Between Reptiles and Amphibians
AmphibiansReptiles
They secrete toxins from their skin to protect themselves from predators.The skin is protected by hard scales, and they also secrete toxin through teeth and nails.
Skin is smooth and highly porous.Skin is dry, hard and scaly.

What are the similarities between amphibians and fish?

Frogs and fish have several such similarities.
  • Vertebrates. Both frogs and fish belong to the phylum Chordata and the subphylum Vertebrata.
  • Exothermic. Both frogs and fish are exothermic, or cold-blooded.
  • Water and Land. In general, amphibians like frogs live on both land and water, and fish live in water.
  • Reproduction.

What are the similarities between reptiles and birds?

We’ll start with the “reptiliansimilarities of birds. Like all other reptiles, birds have scales (feathers are produced by tissues similar to those that produce scales, and birds have scales on their feet). Also, birds lay eggs like other reptiles.

What characteristics do all reptiles have in common?

Traits of Reptiles and Amphibians
  • Reptiles are vertebrates. They have backbones.
  • Their bodies are completely covered with scales.
  • They are cold-blooded.
  • Reptiles produce shelled eggs or bear live young.
  • All species fertilize eggs internally.
  • All species of reptiles have at least one lung.

What is unique about reptiles?

Unlike amphibians, who have moist, slimy skin, reptiles have dry, scaly skin. Their tough skin protects them against injury and prevents moisture loss in arid environments. A reptile’s skin also has a complete covering of keratin, the substance that makes up hair and horns in other animals, for extra toughness.

What three things do reptiles have in common?

As opposed to mammals and birds, reptiles have neither fur nor feathers, but scales. Reptiles cannot be confused with amphibians because reptiles have dry, water-proof skin and eggs, as well as more advanced bodily systems. Reptiles evolved from amphibians 300 million years ago.

What are 5 bird characteristics?

Birds are in the class Aves. All birds have the following key features: they are endothermic (warm-blooded), have two legs, and lay eggs.

Features of Birds

  • Feathers.
  • High metabolism.
  • A four-chambered heart.
  • A beak with no teeth.
  • A lightweight but strong skeleton.
  • Production of hard-shelled eggs.

What are the unique characteristics of birds?

All birds have the following key features: they are endothermic (warm-blooded), have two legs, and lay eggs.

Defining characteristics of modern birds also include:

  • Feathers.
  • High metabolism.
  • A four-chambered heart.
  • A beak with no teeth.
  • A lightweight but strong skeleton.
  • Production of hard-shelled eggs.

What are the major characteristics of fish?

5 Characteristics That All Fish Have in Common
  • All Fish Are Cold-Blooded. All fish are cold-blooded, which is also called ectothermic.
  • Water Habitat. Another shared characteristic amongst all fish is that they live in water.
  • Gills to Breathe.
  • Swim Bladders.
  • Fins for Movement.
  • 5 Basic Needs of an Animal.

What are six features common to all birds?

List six features common to all members of class Aves.
  • Bipedal.
  • Warm-blooded.
  • Vertebrates.
  • Have feathers.
  • Have scaly legs.
  • Have wings.

What are the 7 characteristics of birds?

7 Characteristics of birds
  • Feathers.
  • Wings.
  • lightweight, rigid skeleton.
  • Endothermic metabolism.
  • unique respiratory system.
  • beak.
  • oviparity.

Is characteristic feature of birds?

Birds are endothermic and, because they fly, they require large amounts of energy, necessitating a high metabolic rate. As with mammals, which are also endothermic, birds have an insulating covering that keeps heat in the body: feathers.

What are 6 features common to all birds?

Ch 8
QuestionAnswer
List the six characteristics common to all members of class Aves, both living and extinctbipedal, warm-blooded, vertebrates, feathers, scaly legs, wings
produces oil that birds spread over their featherspreen gland
strong feathers found on a bird’s body, wings and tailcontour

What characteristics do birds and reptiles share?

Birds share many characteristics with reptiles such as being vertebrates, having scales on parts of their bodies, and laying amniotic eggs with shells. B. Birds have unique characteristics such as laying eggs with hard shells, and having feathers, wings, and a beak.