Are Chickens Mammals or Birds or Reptiles

Are Chickens Mammals or Birds or Reptiles?

As an Amazon Associate, I earn from qualifying purchases.

Last Updated on November 1, 2023 by Pauline G. Carter

Are chickens mammals or birds, or reptiles? That is the question most people ask, and it’s not hard to see why. Chickens share lots of characteristics with mammals, birds, and reptiles.

Let’s look closely at their physical traits and anatomy that should help us decide which class they belong to.

How to Recognize a Chicken

How to Recognize a Chicken

Let’s explore the physical characteristics of chickens.

Chickens are exceptional-looking animals. Thanks to their unique appearance, it is easy for most people to tell them apart from other animals. Here are some of the parts a chicken has


The comb lies atop the chicken’s head and is red and fleshy. Usually, roosters have larger combs than the hen. The exact shape of the comb differs from strawberry to buttercup to V-shape.


Chickens have parts called wattles just under their beaks. The wattles, together with the earlobe and combs, are referred to as caruncles.


Chickens Mammals or Birds

The chicken’s hackles are its neck feathers. They give the rooster a classy and elegant look.


The cape is a soft feather located just before the chicken’s tail. It is soft and is often used for making fishing flies.


Some breeds of rooster have sickles. Sickles are long feathers at the fowl’s tail that look like sickles. 


The fluff comprises soft feathers at the bottom of the chicken. They hide its vents and keep it warm. Of course, you must have noticed that chickens have different kinds of feathers. Each is adapted for a unique function, e.g. while some of their feathers keep them warm, others help them fly.


Chickens have four toes, with each toe ending in a claw. The claws are adapted for scratching the soil in search of food.

Are Chickens Birds?

Are Chickens Birds

Technically speaking, chickens are birds, not mammals or reptiles. As birds, they are further classified as fowls – a group of birds raised for their meat and eggs.

Are Chickens Mammals?

There are some characteristics that separate mammals from birds and reptiles. To decide if the chicken is a mammal, we must examine these peculiar characteristics.

Mode of Giving Birth

For a chicken to be classified as a mammal, it has to birth its young alive. However, chickens lay eggs which now grow into young chicks.

Presence of Mammary Glands

Mammals also have mammary glands that they use to feed their young ones. Since chickens do not have any mammary glands, it is safe to say they are not mammals.

Presence of Hair or Fur

Another differentiating characteristics are the presence of hair or fur. Since chickens have neither, they cannot be classified as mammals.

Are Chickens Reptiles?

Are chickens reptiles? That’s a question we get a lot. Let’s look at the Characteristics of reptiles.


Reptiles have scales on them that protect them from intense water loss. The tough scales also give reptiles the ability to thrive in both land and water. Chickens, on the other hand, have feathers that keep them warm and help them fly.


Are Chickens Mammals

Both birds and reptiles have beaks made primarily of keratin. The beak is perfectly modified for rugged activities as it never stops growing.


Fowls have hollow bones to allow them to fly; reptiles also have hollow bones, but they do not fly. This is because of their skeletal structure.

In summary, since reptiles cannot fly, it makes sense to conclude that chickens are not reptiles. They are more like birds: birds fly, have feathers and have hollow bones.

Why Do People Think Chickens are Mammals?

A lot of people consider chickens as mammals because they are often found on farms with other mammals. The fact that chicken meat is also widely consumed is another reason for the wrong classification.

Another reason is that chickens are sometimes raised as pets, just like cats and dogs. Like many mammals, chickens take care of their young until they can fend for themselves.

Chickens like mammals are also warm-blooded, meaning that they have a fairly constant internal body temperature. Usually, their body temperature is higher than that of their surroundings.

Characteristics of Mammals, Birds, and Reptiles?

Mammals, birds, and reptiles all belong to Kingdom Animalia. It is common to find a bit of an overlap in their features and characteristics. However, it is their differences that help us distinguish them correctly. We have outlined some of the key differences between these groups.


Are Chickens Birds or Reptile

Chickens have feathers. That’s the first sign that they are not mammals because mammals have fur or hair. The chicken feathers also perform different functions from the hair or fur on mammals. They keep the bird warm and give it the ability to fly. However, don’t expect your chicken to fly like a bat.

Egg Tooth

Both chicks and reptiles have egg tooth that tends to fall off once they are out of their shells. The egg tooth is positioned at the front of their beak and helps them break out from their shells. On the other hand, Mammals lack egg teeth because they do not need to crack open any shells.


Animals are either cold or warm-blooded. Mammals and chickens are warm-blooded, while reptiles are cold-blooded. This means that reptiles are more comfortable in cooler environments and have a body temperature depending on their environment.

Milk Production

Reptiles and chickens lack mammary glands and so do not produce milk. This means that, unlike mammals, reptiles and chickens do not nurse their young with milk. 

Fun Facts About Chickens

Chickens are precocial. This means that a few weeks after the chicks are hatched, they can fend for themselves. But the parent hens still lead them to food and water and give them all the care they need.

Chickens generally are raised for their meat and eggs. Their meat is high in protein and has low fat, making it a healthy option. They lay eggs without the rooster’s help.


Chickens are domesticated birds, not reptiles or mammals. However, they share some similarities with mammals and reptiles.  

About Author (Pauline G. Carter)

Pauline G. Carter

Pauline G. Carter is a well-known pet blogger who has written about the world of pets for several years. She is passionate about pets, from cats and dogs to birds, reptiles, and poultry. Her blog, which is updated regularly, is filled with articles and guides on pet care, nutrition, and training. She also shares her experiences and observations on pet ownership, making her blog relatable and informative for pet lovers. She is a true animal advocate and is dedicated to promoting responsible pet ownership. Let’s Go …

Scroll to Top