The Cretaceous (pronounced /kriːˈteɪʃəs/), Latin language Latin is an Italic language historically spoken in Latium and Ancient Rome. Through the Roman conquest, Latin spread throughout the Mediterranean and a large part of Europe. Romance languages such as Italian, French, Catalan, Romanian, Spanish, and Portuguese are descended from Latin, while many others, especially European languages, including for "chalky Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. It forms under relatively deep marine conditions from the gradual accumulation of minute calcite plates (coccoliths) shed from micro-organisms called coccolithophores. It is common to find flint and chert nodules embedded in chalk. Chalk can also", usually abbreviated K for its German German (Deutsch, [dɔʏtʃ] ) is a West Germanic language, thus related to and classified alongside English and Dutch. It is one of the world's major languages and the most widely spoken mother tongue in the European Union. Around the world, German is spoken by approximately 105 million native speakers and also by about 80 million non-native translation Kreide (chalk), is a geologic period and system The geologic time scale is a chronologic schema relating stratigraphy to time that is used by geologists, paleontologists and other earth scientists to describe the timing and relationships between events that have occurred during the history of the Earth. The table of geologic time spans presented here agrees with the dates and nomenclature from circa 145.5 ± 4 to 65.5 ± 0.3 million years ago (Ma). In the geologic timescale The geologic time scale is a chronologic schema relating stratigraphy to time that is used by geologists, paleontologists and other earth scientists to describe the timing and relationships between events that have occurred during the history of the Earth. The table of geologic time spans presented here agrees with the dates and nomenclature, the Cretaceous follows on the Jurassic The Jurassic is a geologic period and system that extends from about 199.6± 0.6 Ma to 145.5± 4 Ma, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the "Age of Reptiles". The start of the period is marked by the major Triassic– period and is followed by the Paleogene The Paleogene is a geologic period and system that began 65.5 ± 0.3 and ended 23.03 ± 0.05 million years ago and comprises the first part of the Cenozoic era. Lasting 42 million years, the Paleogene is most notable as being the time in which mammals evolved from relatively small, simple forms into a plethora of diverse animals in the wake of the period. It is the youngest period of the Mesozoic The Mesozoic Era is one of three geologic eras of the Phanerozoic eon. The division of time into eras dates back to Giovanni Arduino, in the 18th century, although his original name for the era now called the "Mesozoic" was "Secondary" . Lying between the Paleozoic and the Cenozoic, "Mesozoic" means "middle era An era is a commonly used word for long period of time. When used in science, for example geology, eras denote clearly defined periods of time of arbitrary but well defined length, such as for example the Mesozoic era from 252 Ma–66 Ma, delimited by a start event and an end event. When used in social history, eras may for example denote a period, and at 80 million years long, the longest period of the Phanerozoic The Phanerozoic Eon is the current eon in the geologic timescale, and the one during which abundant animal life has existed. It covers roughly 545 million years and goes back to the time when diverse hard-shelled animals first appeared. Its name derives from the Greek meaning visible life or appear life, referring to the large size of organisms eon. The end of the Cretaceous defines the boundary between the Mesozoic and Cenozoic The Cenozoic Era (pronounced /ˌsiːnɵˈzoʊɪk/, /ˌsɛnəˈzoʊɪk/) (meaning "new life" (Greek καινός (kainos), "new", and ζωή (zoe), "life"), is the most recent of the three classic geological eras and covers the period from 65.5 million years ago to the present. It is marked by the Cretaceous–Tertiary eras The geologic time scale is a chronologic schema relating stratigraphy to time that is used by geologists, paleontologists and other earth scientists to describe the timing and relationships between events that have occurred during the history of the Earth. The table of geologic time spans presented here agrees with the dates and nomenclature. In many foreign languages this period is known as "chalk period".
The Cretaceous was a period with a relatively warm climate Climate encompasses the statistics of temperature, humidity, atmospheric pressure, wind, rainfall, atmospheric particle count and numerous other meteorological elements in a given region over long periods of time. Climate can be contrasted to weather, which is the present condition of these same elements over periods up to two weeks and high eustatic sea level Mean sea level is the average (mean) height of the sea, with reference to a suitable reference surface. Defining the reference level', however, involves complex measurement, and accurately determining MSL can prove difficult. The oceans and seas were populated with now extinct In biology and ecology, extinction is the death of a species or group of taxa. The moment of extinction is generally considered to be the death of the last individual of that species . Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena marine reptiles Marine reptiles are reptiles which have become secondarily adapted for an aquatic or semi-aquatic life in a marine environment, ammonites Ammonites are an extinct group of marine animals of the subclass Ammonoidea in the class Cephalopoda, phylum Mollusca. They are excellent index fossils, and it is often possible to link the rock layer in which they are found to specific geological time periods and rudists Rudists are a group of bizarrely shaped marine heterodont bivalves that arose during the Jurassic, and became so diverse during the Cretaceous that they were major reef-building organisms in the Tethys Ocean; and the land by dinosaurs Dinosaurs were the dominant vertebrate animals of terrestrial ecosystems for over 160 million years, from the late Triassic period (about 230 million years ago) until the end of the Cretaceous period (65 million years ago), when most of them became extinct in the Cretaceous–Tertiary extinction event. The 10000 living species of birds may be. At the same time, new groups of mammals Mammals are a class of vertebrate animals whose females are characterized by the possession of mammary glands while both males and females are characterized by sweat glands, hair, three middle ear bones used in hearing, and a neocortex region in the brain and birds Birds are winged, bipedal, endothermic (warm-blooded), vertebrate animals that lay eggs. There are around 10,000 living species, making them the most numerous tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Birds range in size from the 5 cm (2 in) Bee Hummingbird to the 2.7 m (8 ft 10 in) Ostrich as well as flowering plants The flowering plants or angiosperms are the most widespread group of land plants. The flowering plants and the gymnosperms are the only extant groups of seed plants. The flowering plants are distinguished from other seed plants by a series of apomorphies, or derived characteristics appeared. The Cretaceous ended with one of the largest mass extinctions An extinction event is a sharp decrease in the number of species in a relatively short period of time. Mass extinctions affect most major taxonomic groups present at the time — birds, mammals, reptiles, amphibians, fish, invertebrates and other simpler life forms. They may be caused by one or both of: in Earth history The history of the Earth describes the most important events and fundamental stages in the development of the planet Earth from its formation to the present day during the last 4.54 billion years. Nearly all branches of natural science have contributed to the understanding of the main events of the Earth's past. The Earth is approximately one, the K-T extinction, when many species, including the dinosaurs, pterosaurs Pterosaurs were flying reptiles of the clade or order Pterosauria. They existed from the late Triassic to the end of the Cretaceous Period (220 to 65.5 million years ago). Pterosaurs are the earliest vertebrates known to have evolved powered flight. Their wings were formed by a membrane of skin, muscle, and other tissues stretching from the legs, and large marine reptiles, disappeared.
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Huntington Herald Dispatch
The film is a great chance to get an up-close view into those bizarre prehistoric waters of the late Cretaceous period, when creatures such as the Archelon, ...
dinosaurspictures
ue, 07 Jul 2009 04:11:43 GM
From the last Triassic ahead, the dinosaurs spread at the race of light to after the ruling earthling animals with four legs until their extinction at the come to an end of the . Cretaceous. . Palaeontologists proceed the earliest bones ...
