Over the past 300 million years, terrestrial ecosystems on Earth have been dominated by tetrapods: four-limbed terrestrial vertebrates (Zimmer, n.d.). Modern examples of tetrapods include amphibians, mammals, reptiles and birds (Hall, 2015). They first evolved from sarcopterygian fishes about 400 million years ago, in the Devonian (Speer, 1995). In the following period, the Carboniferous, tetrapods diversified, including the distant ancestors of modern groups. Early tetrapods had moist skin and laid their eggs in water, like modern amphibians. (Wilcox, 2012) However, it is important to keep in mind that modern amphibians (also called lissamphibians) are a distinct monophyletic group that excludes these primitive tetrapods (Cannatella, 2012). This article will be an analysis of the rise of tetrapods from the Carboniferous Period, and how they diversified into many new forms. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get the original essay The earliest tetrapods that survived the Devonian extinction quickly diversified into many new forms. Some of them, like Perderpes and other members of Whatcheeriid, were more terrestrial than previous tetrapods (Daeschler, 2011). Others, like Crassigyrinus, became more aquatic, reducing their limbs and looking more eel-like (Naish, 2007). Midway through the Carboniferous, the first members of Temnospondyl appear in the fossil record. Temnospondyls share several characteristics, including their uniquely subdivided vertebrae; Unlike modern amphibians, Temnospondyls possessed a lateral line, which is a pressure-sensitive organ that ran along their sides (often found in fish today) (Schoch, 2007). Scales, claws, and bony skin patches have also been found on some members (Savage, 2012). Some Temnospondyls lived entirely in water, such as Brachiosaurus, which had external gills; others were more terrestrial, like the dissorophoids. Temnospondyls were often much larger than modern amphibians (Huttenlocker, 2007). Many Carboniferous temnospondyls were large, crocodile-like predators, such as the meter-long Cochleosaurus; one of the largest was Dendreropeton acadianum, which measured up to three meters long (Godfrey & Holmes, 1995). The majority of evidence seems to suggest that Temnospondyls are the ancestors of modern amphibians. As other tetrapods diversified, some were on their way to fully adapting to life on land. Today, most land vertebrates are amniotes: animals whose embryos develop inside amniotic sacs contained in eggs (or in the mother's body), which frees them from the need to lay eggs. their eggs in water (Duscheck, nd). Reptiliomorpha is defined as all tetrapods that are more closely related to amniotes (mammals, reptiles, and birds) than to modern amphibians; However, because the classifications of these early tetrapods are not very well agreed upon, it is unclear whether or not certain groups fall into the reptiliomorpha category ("Palaeos Vertebrates Reptiliomorpha: Overview", n;.d.). Regardless, many reptiliomorph groups exhibit amniote-like characteristics, including a deeper skull with eyes on the sides of the head rather than on top; their members were more well