Amphibians are vertebrate tetrapods (\u201cfour limbs\u201d), and include frogs, salamanders, and caecilians. The term \u201camphibian\u201d loosely translates from the Greek as \u201cdual life,\u201d which is a reference to the metamorphosis that many frogs and salamanders undergo and the unique mix of aquatic and terrestrial phases that are required in their life cycle. In fact, they cannot stray far from water because their reproduction is intimately tied to aqueous environments. Amphibians evolved during the Devonian period and were the earliest terrestrial tetrapods. They represent an evolutionary transition from water to land that occurred over many millions of years. Thus, the Amphibia are the only living true vertebrates that have made a transition from water to land in both their ontogeny (life development) and phylogeny (evolution). They have not changed much in morphology over the past 350 million years!<\/p>\r\nhttps:\/\/www.youtube.com\/embed\/E1h4kgt2520\r\n
Amphibians are vertebrate tetrapods (\u201cfour limbs\u201d), and include frogs, salamanders, and caecilians. The term \u201camphibian\u201d loosely translates from the Greek as \u201cdual life,\u201d which is a reference to the metamorphosis that many frogs and salamanders undergo and the unique mix of aquatic and terrestrial phases that are required in their life cycle. In fact, they cannot stray far from water because their reproduction is intimately tied to aqueous environments. Amphibians evolved during the Devonian period and were the earliest terrestrial tetrapods. They represent an evolutionary transition from water to land that occurred over many millions of years. Thus, the Amphibia are the only living true vertebrates that have made a transition from water to land in both their ontogeny (life development) and phylogeny (evolution). They have not changed much in morphology over the past 350 million years!<\/p>\n