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Dinosaur Blackout Page 15
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Note: Creta is the Latin word for chalk. The Cretaceous Period is named for the chalky rock from southeastern England that was the first Cretaceous Period sediment studied.
global warming:
Global warming is the term used to describe the increase in the average temperature of the earth’s near-surface air in recent decades and its projected continuation. This is caused by trapping too much of the greenhouse gases in the atmosphere.
greenhouse effect:
The greenhouse effect was first discovered in 1824 by Joseph Fournier and studied more fully in 1896 by Svante Arrhenius. It is the process in which emissions of infrared radiation warm a planet’s surface. Infrared radiation occurs when the sunlight creates energy or heat and it is reflected back into space. The greenhouse effect occurs when some of these emissions are trapped by greenhouse gases.
greenhouse gases:
These are a group of gases in the atmosphere that help stop the sun’s infrared radiation (heat) from escaping into space, which is called the greenhouse effect. Some of these greenhouses gases are necessary to keep the earth warm enough to live on.
There are two major types of greenhouse gases. Those that occur naturally and those which result from gases emitted as a result of human activities. When too much of the man-made greenhouse gases are unable to escape to space, this causes global warming.
iridium:Iridium is a rare element on earth, but is found abundantly in meteors. Deposits of iridium left in craters have helped to identify the gouges as made by meteors hitting the earth.
k-t mass extinction:
K-T stands for Cretaceous-Tertiary. “K” is for Kreide – a German word meaning chalk, the sediment layer from that time. “T” is for Tertiary, the geological period that followed the Cretaceous Period. About 65 million years ago, it is believed that all land animals over 25 kg (55 pounds) went extinct, as well as many smaller organisms. This included the obliteration of the dinosaurs, pterosaurs, large sea creatures like the plesiosaurs and mosasaurs, as well as ammonites, some bird families, and various fishes and other marine species. There are many theories as to why this mass extinction occurred, but many scientists favour the one of an extraterrestrial body, a meteor, or asteroid hitting the earth.
During the K-T extinction, it has been estimated that 80-90% of marine species, about 50% of the marine genera, and about 15% of the marine families went extinct. For land animals, about 85% of the species, about 25% of the families, and about 56% of the genera died out. Larger animals (over about 55 pounds = 25 kg) were all wiped out.
meteorite craters:
There are many meteorite craters all over the earth. Those over 100 km in diameter had significant effects on the extinction of the species. Some of the biggest craters include one in the Yucatan province of Mexico; the Barringer Meteorite Crater near Flagstaff, Arizona, and others in Australia, Europe and North America. In Canada there are several in Quebec and some in Ontario, Nova Scotia, Manitoba, Newfoundland and Saskat-chewan. The most famous in Saskatchewan is the Carswell Crater by Cluff Lake in the northern part of the province.
palentology (PAY-lee-on-TALL-o-gee):
Paleontology is the branch of geology and biology that deals with the prehistoric forms of life through the study of plant and animal fossils.
phytoplankton (FEE-toe-PLANK-ton):
Phytoplankton are minute, free-floating aquatic plants.
photosynthesis (FOE-toe-SIN-the-sis) (photo=light, synthesis=putting together):
In order for plants to make food for themselves, they use a method called photosynthesis. The “green” part of the leaves (chlorophyll) captures light from the sun, using it to form a sugar along with carbon dioxide and water. Plants release oxygen as a by-product of photosynthesis.
tertiary period (TUR-sheer-ee):
The Tertiary Period is the name for a portion of the most recent geological era known as the Cenozoic era, also known as the “Age of Mammals,” which lasted from about 65 to 2 million years ago. The term Tertiary was coined about the middle of the eighteenth century and refers to a particular layer of sedimentary deposits. Many mammals developed during that time, including primitive whales, rodents, pigs, cats, rhinos, and others familiar to us today.
volcanic activity:
Prehistoric volcanoes created dramatic changes in greenhouses gases and global warming of the earth. They raised sea temperatures and killed off many marine species. (See K-T Mass Extinction for details of species that died.) Today they are mostly found in the northern hemisphere, but in prehistoric time they were found in the south. They spewed deadly amounts of ash, pumice and carbon dioxide into the air.
CREATURES MENTIONED IN THE BOOK
ankylosaurs (AN-kye-loh-sawrs):
A group of armoured, plant-eating dinosaurs that existed from the mid-Jurassic to the late Cretaceous Periods. Ankylosaurus was a huge armoured dinosaur, measuring about 7.5–10.7 m long, 1.8 m wide and 1.2 m tall; it weighed roughly 3–4 tonnes. Its entire top side was heavily protected from carnivores with thick, oval plates embedded (fused) in its leathery skin, two rows of spikes along its body, large horns that projected from the back of the head, and a clublike tail. It even had bony plates as protection for its eyes. Only its underbelly was unplated. Flipping it over was the only way to wound it.
basilemys (BAH-zil-emm-ees):
A tortoise-like creature with a shell up to 1.5 metres across. This is the largest known fossil turtle from the Frenchman River Valley.
borealosuchus (BOR-ee-al-o-such-us):
A crocodile in existence in the late Cretaceous Period in Saskatchewan. This crocodile would be little compared to its earlier ancestors, about two to three metres in length. It would be running from a T. rex as opposed to taking it head-on like the larger crocodiles.
champosaurs (CHAMP–oh-SAWRS):
Most of the champosaurs are fairly small, reaching only about 1.5 meters in length, but some specimens over three meters (about 10 feet) in length have been recently found in North Dakota. They had long, narrow jaws with fine, pointed teeth, and closely resemble the modern gavial of India. They may look like crocodiles, but are not closely related to them. Champosaurs fed on fish, snails, mollusks, and turtles. They lived in Saskatchewan from about 75 million years ago to about 55 million years ago.
cimoloptertx (sim-oh-LOP-ter-icks) (“Cretaceous wing”):
An early bird resembling typical shorebirds of today and found in the late Cretaceous Period in Saskatchewan. These birds had long, slender bills and long, strong legs for wading and running. They probably probed in the sand or mud for food.
corythosaurus (co-RITH-oh-SAWR-us) (“Helmet lizard”):
Corythosaurus was a large plant-eating duck-billed dinosaur that probably fed on palm leaves, pine needles, seeds, cycad ferns, twigs, magnolia leaves and fruit. It may have weighed up to 5 tonnes and was about 2 metres tall at the hips and 9 to 10 metres long. (NB: Corythosaurus are known from slightly older sediments.)
dromaeosaurus (DRO-mee-o-SAWR-us) (“fast-running lizard”):
Dromaeosaurus was a small, fast, meat-eating, theropod dinosaur about with sickle-like toe claws, sharp teeth, and big eyes. It lived during the late Cretaceous Period and was about a half a metre tall at the hips and 1.8 m (6 feet) long, weighing roughly 15 kg. Fossils have been found in Alberta, Saskatchewan and Montana. They were very smart, deadly dinosaurs and may have hunted in packs.
edmontosaurus (ed-MON-toh-SAWR-us) (“Edmonton [rock formation] lizard”):
A large, plant-eating member of the duckbill dinosaurs, or hadrosaurs that lived about 73 to 65 million years ago in the Cretaceous Period in western North America. It had hundreds of teeth crowded together in the huge jaw, enabling it to eat tough leaves and other vegetation. This flat-headed duckbill grew to 13 metres and weighed 3.1 tonnes. It may have had anywhere from 800 to 1600 teeth. Edmontosaurus Saskatchewanensis, named in 1926 by Sternberg, is the only identified species of Edmontosaurus so far known from Saskatchewan.
/> garfish (A.S. gar, “spear”):
Garfish is a name commonly given to certain fishes with long, narrow bodies and bony, sharp-toothed beaks. Primarily freshwater fish, today the largest tropical gar reach lengths of 3.7 metres. They are a primitive fish that have existed for millions of years. They have needlelike teeth, a dorsal fin that sits far back on the heavily scaled body. They are able to breathe in stagnant water, and their roe is poisonous to many animals, including humans.
hadrosaurs (HAD-roh-SAWRS)(“bulky lizards”):
Hadrosaurs were a family of duck-billed dinosaurs that ranged from seven to ten metres long and lived in the late Cretaceous Period. They appear to have been highly social creatures, laying eggs in nests communally. Nests with eggs have been found in both Alberta and Montana. The only known hadrosaur in Saskatchewan is the Edmontosaurus Saskatchewanensis (see description above).
hesperonis (HES-per-OR-nis) (“western bird”):
Hesperornithids were a family of large flightless birds that swam in the oceans of the late Cretaceous and preyed on small fish. It has been found in the Upper Cretaceous of Western Kansas and Saskatchewan. It is likely that they swam and fed much like modern penguins. They were also apparently limited to the Northern Hemisphere, much like penguins are limited to the Southern Hemisphere today.
ichthyornis (ik-thee-ORN-is) (meaning “fish bird”):
Ichthyornis were toothed, tern-like birds, with large beaks and heads, dating from the Cretaceous Period. Although only about 20 cm long, they were powerful flyers and the oldest-known birds to a keeled breastbone (sternum) similar to modern birds. It lived in flocks nesting on shorelines, and hunted for fish over the seas. Fossils have been found in Kansas and Texas and Alberta,.
mosasaurs (MOES-ah-SAWRS):
Mosasaurs were a group of giant, lizard-like marine reptiles that extended 12.5 to 17.6 metres long. They were not dinosaurs, but may be related to snakes and monitor lizards. They were powerful swimmers, adapted to living in shallow seas. These carnivores (meat-eaters) still breathed air. A short-lived line of reptiles, they became extinct during the K-T extinction, 65 million years ago.
pteranodons (tair-AH-no-dons):
Pteranodons were large members of the pterosaur family from the Cretaceous Period. They were flying prehistoric reptiles, not dinosaurs, toothless hunters who scooped up fish from the seas. About 1.8 m long, they had a 7.8 m wing-span.
pterodactylus (ter-oh-DAK-til-us) (“winged finger”):
A flying, prehistoric reptile was a member of the pterosaurs group, with a wingspan that spread up to .75 metres. The wing was made up of skin stretched along the body between the hind limb and a very long fourth digit of the forelimb. They lived during the late Jurassic period.
pterosaurs (TER-o-SAWRS) (“winged lizards”):
Flying reptiles that included Pteranodons and Pterodactylus, they were the largest vertebrates ever known to fly. They lived from the Jurassic to the Cretaceous Period.
purgatorius (pur-go-TOR-ee-us):
A small, rodent-sized mammal from the Cretaceous Period, they may have been about ten centimetres long and probably weighed no more than 20 grams. They fed on insects. Some have suggested that this mammal may have been the earliest primate known.
“scotty”:
Scotty is the Tyrannosaurus rex discovered in 1991 near Eastend, Saskatchewan by a schoolteacher. Surrounded by cement-like ironstone and sandstone, it was not unearthed until 1994–95 and was found to be one of the most complete T. rex skeletons of only twelve such discoveries in the world. At this time, the first coprolite – or fossilized dung – that can be attributed to a T. rex was also found.
stegoceras (STEG-oh-CEER-us) (“roofed horn”):
A bipedal, herbivorous, dome-headed, plant-eating dinosaur from the late Cretaceous Period about 76 to 65 million years ago. The Stegoceras was about two metres long and lived in what is now Alberta. Its large head housed a thick skull, a relatively large brain, and large eyes. Its skull was about 8 centimetres thick. Males had thicker domes than females, and older Stegoceras had thicker domes than younger ones. Stegoceras had a fringe of horny knobs along the rear of its skull. It had short forelimbs and a large, stiff tail. Stegoceras grew to be about 2.1 metres long and 1.2 metres tall. This plant-eater weighed roughly 78 kilograms. (Not to be confused with a Stegosaurus [pronounced STEG-oh-SAWR-us], meaning “roof lizard,” a plant-eating dinosaur with armoured plates along its back and tall spikes that lived during the Jurassic Period, about 156 to 150 million years ago.)
stygimoloch (STIJ-eh-MOLL-uk) (“thorny devil” or “demon from the River Styx”):
This unusual-looking plant-eating dinosaur lived in the woodlands. It had a domed head with bumps on its skull, which was rimmed with many bony spikes up to 100 mm long. It was about 3 metres long, and weighed about 50–75 kg. This pachycphalosaurid dinosaur lived during the very late Cretaceous period, about 68 million–65 million years ago. Only parts of Stygimoloch’s skull have been found in Montana and Wyoming and in Alberta. The Stygimoloch was named after the River Styx of Greek mythology and because it was found near Hell Creek.
thescelosaurus (THES-ke-loh-SAWR-us) (“Marvellous lizard”):
This plant-eating dinosaur had a small head, a bulky body that was 3–4 metres long, and less than one metre tall at the hips. A member of the ceratopsian group, it also had a long, pointed tail and shorter arms and could probably run at about 50 km/hr for an extended time. Two partial skeletons have been found in Saskatchewan.
torosaurus (TOR-oh-SAW-rus) (“pierced lizard”):
Torosaurus had a strong toothless beak that was able to handle the toughest vegetation including small branches. A member of the ceratopsian group, it had a fierce appearance due to the two brow horns on its enormous 2.5 metre skull, a short nose horn, and a long-frilled crest. Its powerful legs were shorter at the front and longer at the back, which gave it a very stable posture. Torosaurus could chew well with its cheek teeth. They lived about 70–65 million years ago, and fossils have been found in the United States in Wyoming, Montana, Colorado, South Dakota, New Mexico, Texas, Utah and in Canada in Saskatchewan.
triceratops (tri-SER-uh-tops):
Triceratops was a rhinoceros-like dinosaur with a bony neck frill that lived about 72 to 65 million years ago. From the ceratopsian group, this plant-eater was about 8 metres long, 3 metres tall, and weighed from 6–12 tonnes. A
relatively slow dinosaur, it had had three horns on its head and its parrot-like beak held many cheek teeth and a set of powerful jaws. It had a short, pointed tail, a bulky body, column-like legs with hoof-like claws. Many Triceratops fossils have been found, mostly in the western United States an in western Canada, including Saskatchewan.
troodon (TROH-oh-don):
A very smart, human-sized, meat-eating dinosaur from the late Cretaceous Period. Fossils of Troodon have been found in Montana, Wyoming, Alberta and Saskatchewan. It may have been one of the smartest dinosaurs, because it had a large brain compared to its body size.
tyrannosaurus rex (tye-RAN-oh-SAWR-us recks or Tie-ran-owe-saw-rus-recks) (“tyrant lizard king”):
A huge, meat-eating theropod dinosaur from the late Cretaceous Period. The largest meat-eater that has ever been, it stood 5–7 metres tall on its great clawed feet and had terrible, dagger-like teeth, 15 centimetres long. Tyrannosaurus rex was roughly 5–7 tons in weight. The enormous skull was about 1.5 metres long. The eye sockets in the skull are 10.2 centimetres across; the eyeballs would have been about 7.6 centimetres in diameter.
zapsalis (ZAP-sa-lis) (“through shears”):
A meat-eating dinosaur (a theropod) that lived during the Cretaceous Period. This theropod was found in the Judith River Formation, Montana in 1876. It is only known through its teeth and is currently classified as a troodontid.
OTHER REFERENCES & NOTES
bees:
Over the past few years, Stephen Hasiotic, a Colorado University doctoral student and geology lab instructo
r, has found nests, almost identical to modern honeybee nests, that date back 207 to 220 million years, or about twice as far back as the oldest fossils of flowering plants. This means bees have been around longer than previously thought. The ancient bees could have found sugars and nutrients – which they find today in the nectar of flowers – in coniferous plants or even in animal carcasses.
coprolite:
Coprolite – or fossilized dung – has been found in many areas, but the specimens found in 1994–95 with “Scotty” in the Frenchman River Valley was the first that could be officially be attributed to a T. rex. This was an important discovery as it provides insights into its environment and eating habits.
dragonflies:
Dragonflies, primitive flying insects that can hover in the air, evolved during the Mississippian Period, about 360 to 325 million years ago. Huge dragonflies with wingspans up to 70 centimetres existed during the Mesozoic Era (when the dinosaurs lived).
environmental scientists:
Environmental scientists and hydrologists use their knowledge of the physical makeup and history of the Earth to protect the environment, study the properties of underground and surface waters, locate water and energy resources, predict water-related geologic hazards, and offer environmental site assessments and advice on indoor air quality and hazardous-waste-site remediation. (Taken from: http://www.bls.gov/oco/ocos050.htm)