What is Deuterostome and its characteristics

Deuterostoma is a branch in the animal kingdom that describes a particular pattern of embryonic development. Deuterostoma refers to a type of embryonic development in which the blastopore (the first opening in the embryo) develops into the anus, while the mouth forms from a new formation called the stomodeum.

What’s that

Deuterostoma is an evolutionary classification that includes animals that have a distinctive body structure. Deuterostoma animals have mouths that appear after the heart, in contrast to protostoma animals which have mouths that appear before the heart.

Deuterostomes also have strong evidence of an embryo, where the head of the embryo is made of a layer of rigid cells, while the lungs and urinary tract are formed from a layer of soft cells within the blastula. Examples of deuterostome animals are marine animals such as shrimp and bats, as well as land animals such as goats and giants.


Some of the main characteristics of Deuterostoma are as follows:

  1. Blastopore produces anus: In the early stages of embryo development, the blastula (embryo at the small ball stage) undergoes a gastrulation process in which cell re-alignment occurs and the formation of three germ layers: endoderm, mesoderm, and ectoderm. In deuterostomes, the blastopore develops into the anus, so that the main body cavity is connected to the external environment through this opening.
  2. The mouth is formed from the stomodeum: In contrast, the mouth in deuterostomes develops from the stomodeum, which is an invagination on the surface of the embryo which ultimately forms the mouth structure. This is in contrast to protostomes, another branch of the animal kingdom, where the blastopore develops into a mouth and the anus forms later.


Some groups of animals included in deuterostomes are as follows:

  • Echinoderms: Includes starfish, sea urchins, and sea urchins.
  • Chordata: Includes vertebrates such as fish, amphibians, reptiles, birds, and mammals, as well as invertebrates such as lancets and tunicates.

Deuterostomes have an important role in the evolution and diversity of animal life. The different patterns of embryonic development in deuterostomes provide the basis for anatomical and physiological differences between animal groups belonging to this branch.


Deuterostoma is a major division in the animal kingdom. Here are five questions and answers about Deuterostoma:

1. What is Deuterostome?

Deuterostoma is a taxonomic group that includes several animal phyla, such as Chordata (which includes vertebrates), Echinodermata (which includes starfish and sea urchins), and Hemichordata (which includes acorn worms). Deuterostomes are characterized by their embryonic development, which involves the formation of the anus before the mouth.

2. What is the difference between Deuterostoma and Protostoma?

Deuterostoma and Protostoma are the two main developmental patterns in animals. The main difference lies in the formation of the mouth and anus during embryonic development. In Deuterostomes, the anus forms first, followed by the mouth, while in Protostomes, the mouth forms first, followed by the anus.

3. What are examples of Deuterostomes?

Some examples of Deuterostomes include humans, birds, reptiles, fish, starfish, sea urchins, and acorn worms. This organism exhibits typical embryonic development and other characteristics that define the Deuterostoma group.

4. What is the importance of Deuterostoma?

Deuterostomes represent a diverse group of animals with complex body shapes and specialized adaptations. They have played an important role in the evolution of life on Earth. Vertebrates, a subphylum of Deuterostomes, have evolved into the most diverse and successful group of animals.

5. How do Deuterostomes relate to human evolution?

Humans belong to the phylum Chordata in the Deuterostoma group. Chordata have certain characteristics, such as the notochord (which is the backbone in vertebrates) and the dorsal nerve cord. By studying the evolution and development of Deuterostomia, scientists gain insight into the origins and characteristics of humans and other vertebrates.

These questions and answers provide a basic understanding of Deuterostoma and their significance in the animal kingdom. If you have further questions or need clarification, please ask!