Shark (Wikipedia)Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the Batoidea (rays and kin). Some sources extend the term “shark” as an informal category including extinct members of Chondrichthyes (cartilaginous fish) with a shark-like morphology, such as hybodonts. Shark-like chondrichthyans such as Cladoselache and Doliodus first appeared in the Devonian Period (419–359 million years), though some fossilized chondrichthyan-like scales are as old as the Late Ordovician (458–444 million years ago). The earliest confirmed modern sharks (selachimorphs) are known from the Early Jurassic around 200 million years ago, with the oldest known member being Agaleus, though records of true sharks may extend back as far as the Permian.
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Rattlesnake Ridge (Wikipedia)Rattlesnake Ridge, known as daʔšədabš to the Snoqualmie people, is the ridge of Rattlesnake Mountain located south of North Bend, Washington, United States. The western end is near the intersection of State Route 18 and I-90 in Snoqualmie, Washington, and runs southeast about 7 miles (11 km) or 11 miles (18 km) by trail. It is the highest and easternmost of the Issaquah Alps (although Cedar Butte in the gap between Rattlesnake Mountain and the Cascade front at Mount Washington is considered by Harvey Manning to be a quasi-Alp). A maze of abandoned logging roads and constructed trails have been strung together to provide a 10.5-mile (16.9 km) footpath from the Snoqualmie Point trailhead at Exit 27 on I-90 all the way to the Rattlesnake Lake trailhead near Exit 32.
