Jurassic Seas essays

Jurassic Seas essays The sea, being such a rich and vast environment, logically holds a plethora of animals ranging from mammals, reptiles, fish, and so forth. It still remains a place of mystery, danger, and wonder in the modern world today for all those who have ever seen it, though it no longer harbors one of its greatest predators, the ichthyosaurs. In Rulers of the Jurassic Seas, Ryosuke Montani uses personal experience and proven fact to unravel a bit of the mystery surrounding such a creature, explaining its murky origins, its evolution, its swimming style, its decent into the deep, and its ultimate extinction. Primarily, Montani presents information explaining that the ichthyosaurs evolved from not fish, but land-dwelling animals. Their adaptation for water made them quite successful, and able to rule the sea from 245 million to about 90 million years ago approximately the entire time dinosaurs existed on earth. Widely spread out fossils around the world indicate that they migrated extensively, and despite their aquatic appearance, they were most definitely air-breathing reptiles. Montani states that they did not have gills, and their jaw had all the features and traits of that of a reptile. Moreover, they obtained two pairs of limbs, which hinted that perhaps their ancestors once lived on land. All of the stated conclusions were drawn only by the study of one rather late, fish-shaped ichthyosaurs. Their ancestor was built more for land, having stout legs while the later versions obtained flippers, a boneless tail fluke, and a dorsal fin. With the new adaptations and loss of old f eatures, it would have made it difficult to recognize their cousins on land. Due to this lack of evidence, early scientists had no idea as to which vertebrate group they should place the ichthyosaurs. As time progressed, scientists developed new techniques on how to better decipher the relationships among various species. Afterward, most agreed...