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	Tiktaalik roseae Tiktaalik roseae  (after  )
	Tiktaalik roseae was a lobe-finned fish and tetrapodomorph, or a transitional form between fish and tetrapods, the first land animals. Dating from the Late Devonian period at 356-374 mya, Tiktaalik was discovered in southern Ellesmere Island in Nunavut Territory, in the Arctic region of Canada. Tiktaalik belongs to the class Sarcopterygii (lobe-finned fish), the subclass Tetrapodomorpha, and the order Elpistostegalia, considered more closely related to tetrapods than osteolepiform fishes (Camp and Allison 1961).      Tiktaalik is an Inuktitut word meaning burbot, a freshwater fish related to the true cod. The holotype fossil of the type species T. roseae (NUFV 108) consists of the skull and pectoral (shoulder) region, and the remainder of the skeleton has also been recovered. The pectoral fin of the skeleton is composed of bones homologous to the humerus, ulna, and radius of the tetrapod, followed by a host of smaller bones anchoring the fin rays. The pelvic fin skeleton similarly has femur, tibia, and fibula. The body length is 1-3 m. Its neck and ribs were similar to those of tetrapods, with the ribs being used to support its body and aid in its breathing via lungs (Daeschler et al. 2006).     Tiktaalik was a shallow-water fish which had evolved a shift in propulsion apparatus, from tail fins to pectoral and pelvic fins, and a reliance on lungs rather than gills. Both were adaptations to inland freshwater zones.  Tiktaalik had rows of sharp teeth,  and well developed jaws suitable for catching prey, both indicating a predator fish. Tiktaalik is considered one of the best candidates for the earliest known tetrapod-like fish who was the ancestors of all land animals.     References: Camp, C.L. and H.J. Allison 1961. Bibliography of Fossil Vertebrates, 1949-1953 Geological  Society of America Memoir, Vol 84  Daeschler, E.B., N.H. Shubin, and F.A. Jenkins 2006. A Devonian tetrapod-like fish and the evolution of the tetrapod body plan. Nature 440:757-63
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