When it has four limbs, a pair of eyes, a pair of ears, and a well defined set of teeth, it’s most definitely an animal. What’s now the case for an individual that possess beak, a pair of wings and soars majestically through the air for most part of its life? Is it still an animal?
This article discusses whether or not birds are considered members of the animal kingdom.
Is bird an animal?
Yes, birds are animals. They are regarded as animals because they fulfill the necessary criteria that qualify any living organism to be classified as an animal. Within the animal kingdom, birds make up the animal class known as Aves. The other five classes include mammals, reptiles, fish, amphibian and invertebrates.
Why are birds regarded as animals?
There are five different kingdoms of living organisms: Animals, Plantae, Protista, Fungi, Eubacteria and Archaebacteria, among which birds belong to the Animal group.
The classification of organisms into each group is based on some general traits and characteristics that the organisms share.
Animals have many features and traits that helps distinguish them from all other living organisms.
These features on their own cannot serve as the distinguishing traits of members of the animal kingdom from individuals of other kingdoms, but when collected together, they form the fine line that helps biologist to be able to identify animals from members of the rest of the kingdoms. Some of these traits include:
- Animals have eukaryotic cells, meaning that at the very root of their structures are individual cells that have highly specialized structures called organelles and a true nucleus which bounds or surrounds their DNA. The other type of cell structure is known as prokaryotic cell, the cells do not have organelles nor do they have true nucleus encasing the DNA. Aside from animals, plants, protists, and fungi also have eukaryotic cells. The presence of an eukaryotic cell helps distinguish animals from the other two kingdoms remaining of living things.
- Animals have multicellular cells. This means that they consist of more than one cell. Take a good look at your body structure and you’ll confirm this. Plants and fungi too have multicellular cells, but the rest of the kingdoms don’t.
- Animals have highly specialized cells. Their cells come together (multicellular) to develop into different tissues such as the nervous tissues, muscle tissues, connective tissues and epithelial tissues, and eventually organs such as brains, liver, lungs, etc.
- Animals feed on other organism to derive sustenance. This trait helps distinguish animals from most plants and fungi which make their own food.
- Most animals reproduce sexually. Plants, bacteria and fungi can also reproduce sexually.
- Most animals have the ability to move in at least one life cycle stage of theirs. This help differentiate animals from plants and fungi.
- Animals have well developed nervous system. They have brains they can also use to make complex decisions.
These are not all the features that conjure up the fine line between animals and the other kingdoms, there are far too many to start listing here, and birds, just like mammals, insects and fishes, perfectly fulfil most if not all of these criteria. That’s why they are referred to as animals.
Classification of birds
Birds are vertebrate animals (animals with backbones) that soar through the air for most part of their lives. Birds belong to the class of animals known as Aves, which belongs to a bigger group of animals known as Chordate which (further backwards), belong to the kingdom Animalia and ultimately to the Eukaryotic domain.
Sub-class (Main groups)
— Birds are split in nearly 30 different groups some of which include: the albatrosses and petrels, birds of prey, buttonquails, flamingos and game birds (i.e turkeys).
Examples of birds include:
- Secretary bird
- Laughing kookaburra
How are birds different from humans (mammals)?
Several different traits exist which makes birds share a different class from humans and other mammals. Some of these traits on their own, just like with the previous traits justifying the classification of birds into animal kingdom, cannot serve as a distinguishing feature between these two. Some members of the other class group can also have these traits, but the thing to be noted is that the class having that trait as a part of their characteristics, certainly have a majority of their members fulfilling such traits. And when these traits are collected together, they form the basis for separation of bird into different classes from mammals. Some of the most prominent traits that set apart birds from humans include:
- Birds have feathers, mammals have body hairs. Both the feathers in birds and body hairs in mammals serve as a means of thermoregulation, but bird feathers also have additional functionalities such as; to aid flight, to serve as means of communication and camouflage through colors and also to make the animals water resistant and waterproof. Virtually all birds’ possess feathers which is the main distinguishing feature from mammals that do not possess feathers, although some lizard species which are both non mammals and birds can have feathers. So feather is a distinguishing feature of birds from mammals but not from lizards.
- Most birds are able to fly whereas only one mammalian specie, the bats, have been observed to do so, the rest that mimic flying either glide or parachute. Birds aren’t the only members of the animal kingdom that fly however, insects like grasshoppers and butterflies can easily take into the air too. So flying is a trait that distinguishes birds from most mammals but not from insects and other non-avian fliers.
- Birds have toothless beaked jaws whereas most mammals have jaws equipped with teeth and having lips covering the mouth area. The beaks of birds are the equivalent or the same thing as the lips of mammals, but are not mobile unlike in mammals due to the absence of muscles to cause motion. Only a few mammals lack teeth in their mouth, but virtually all birds lack teeth for chewing and grinding so they use their beaks to pieces food and then swallow whole.
- Most birds lay hard shelled eggs from which their embryos develop and hatch out. Mammals on the other hand, mostly give birth to live altricial young after a relatively period of gestation than birds. The exception to this is of course the monotermes mammals which are the platypus and echidna that lay eggs. Both birds and mammals take care of their young after birth unlike reptiles and fishes.
- Birds have wings to fly whereas most mammals have limbs for locomotion which can be greatly reduced or modified as is the case with aquatic species.
- Birds are generally smaller in size compared to mammals. Even so, birds as heavy as 160 kg have been recorded as is the case with ostriches. And likewise, mammals as small 2 grams also exist too, i.e the bumblebee bat.
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Cite this Article ” (APA Format)
Bunu. M. (2020, May 21). Is bird an animal?. Retrieved from http://emborawild.com/is-bird-an-animal/