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The white-tailed deer is the state mammal of Ohio. This list of mammals of Ohio includes a total of 70 mammal species recorded in the state of Ohio. [1] Of these, three (the American black bear, Indiana bat, and Allegheny woodrat) are listed as endangered in the state; four (the brown rat, black rat, house mouse, and wild boar) are introduced; three (the gray bat, Mexican free-tailed bat and ...
The trackways are late Middle Devonian in age based on a palynological assemblage from the Valentia Slate Formation and the U-Pb radioisotopic dating of an interstratified air-fall tuff bed to ca. 385 Ma, [3] making these tetrapod trackways some of the earliest recorded, along with traces of early Middle Devonian (Eifelian) age from Poland. [4]
The oldest near-complete tetrapod fossils, Acanthostega and Ichthyostega, date from the second half of the Fammennian. [56] [57] Although both were essentially four-footed fish, Ichthyostega is the earliest known tetrapod that may have had the ability to pull itself onto land and drag itself forward with its forelimbs. There is no evidence that ...
Lepospondyl and tetrapod classification is still controversial, and even recent studies have had doubts about lepospondyl monophyly. For example, a 2007 paper has suggested that adelospondyls are stem-tetrapods close to colosteids [ 5 ] and a 2017 paper on Lethiscus has Aïstopoda in the tetrapod stem based on their primitive braincase. [ 18 ]
It looked much like a stocky version of the great white shark, but was much larger with fossil lengths reaching 20.3 metres (67 ft). [10] Found in all oceans [ 11 ] it was one of the largest and most powerful predators in vertebrate history, [ 10 ] and probably had a profound impact on marine life. [ 12 ]
The evolution of tetrapods began about 400 million years ago in the Devonian Period with the earliest tetrapods evolved from lobe-finned fishes. [1] Tetrapods (under the apomorphy-based definition used on this page) are categorized as animals in the biological superclass Tetrapoda, which includes all living and extinct amphibians, reptiles, birds, and mammals.
As a very basal (primitive) tetrapod, it falls under the traditional class Amphibia in Linnaean taxonomy. Pederpes is an important fossil because it comes from the period known as Romer's gap and provides biologists with rare information about the development of tetrapods in a time when terrestrial life was rare.
Tiktaalik, a tetrapodomorph with wrists, straddles the fish-tetrapod divide. The Stem Tetrapoda are a cladistically defined group, consisting of all animals more closely related to extant four-legged vertebrates than to their closest extant relatives (the lungfish), but excluding the crown group Tetrapoda.