Seymouria was a reptile-like tetrapod from the early Permian of North America and Europe. It was small, only 2 ft (60 cm) long. Seymouria was well adapted to life on land, with many reptilian features–so many, in fact, that it was first thought to be a primitive reptile.

Tradition and Wikipedia reports that “Diadectes is an extinct genus of large, very reptile-like amphibians.” This is an outdated hypothesis that has to go. Wiki further reports, “Diadectes combines a reptile-like skeleton with a more primitive,seymouriamorph-like skull.”

Diadectes was a heavily built animal, 1.5 to 3 m (5 to 10 ft) long, with a thick-boned skull, heavy vertebrae and ribs, massive limb girdles, and short, robust limbs. The nature of the limbs and vertebrae clearly indicates a terrestrial animal.

Seymouria

Some scientists believe that this animal is actually a missing link between amphibians and reptiles. However, like all amphibians, it still would have had to return to water to lays its eggs. Seymouria was a carnivore which would have fed on smaller reptiles and amphibians.

Yes, a lot of amphibians have teeth. However, they do not have the same kind of teeth that we have. They have what are called vomerine teeth that are only located on the upper jaw and are only in the front part of the mouth.

Echidna and Ornithorhynchus are monotremes that lay eggs and only the group of mammals that do so. So, they are called as ‘connecting link’ between reptiles and mammals.

Complete answer Option A: Lungfish Protopterus is a connecting link between fishes and amphibians. It has the characteristics of both the fishes and amphibians in them. It is also considered as the missing link between fish and amphibians.

Australia

Duck-billed platypus (Ornithorhynchus) is a connecting link between reptiles and mammals. It shows reptilian characters in having a large coracoid in pectoral girdle and in laying eggs with yolk and shell.

Archaeopteryx is known as missing/connecting link because it is a fossil and has characters between. A. Fishes and Amphibians.

Platypus lays eggs like amphibians but shows the presence of mammary glands as well. Thus, Duck billed platypus is a connecting link between Amphibia and Mammalia.

The body of Peripatus shows certain structures that are similar to annelids and other structures found in arthropods. Therefore, they are regarded as the connecting link between Annelids and Arthropods. B) Chaetopterus is an annelid commonly known as parchment tube worm.

Both Annelida and Arthropoda are composed of segmented animals. The main difference between Annelid and Arthropoda is that Annelida consists of a hydrostatic skeleton whereas Arthropoda consists of an exoskeleton made up of chitin.

Connecting link is an organism having characteristics of two different group of organisms e.g, duck-billed platypus ( scientific name Ornithorhynchus anatinus) is a connecting link between reptiles and mammals i.e, it has mammary glands to feed its young ones like other mammals e.g human being, cow, buffalo etc., and …

The living animals which possess characters of two different groups of animals are known as connecting links. On the other hand, missing links are those extinct organisms which had the characters of two different groups of animals.

Many of the famous discoveries in human evolution are often termed “missing links”. For example, there were the Peking Man and the Java Man, despite the fact that these fossils are missing. Transitional forms that have not been discovered are also termed missing links; however, there is no singular missing link.

Archaeopteryx is an iconic fossil, often thought of as the ‘missing-link’ between dinosaurs and birds. It was first described in 1861 by the German palaeontologist Hermann von Meyer (1801-1869).

C)The correct answer is C – Ichthyostega is a missing link. It is a missing link between fish and amphibians. Ichthyostega possess…