Troodon

Troodon is a relatively small, bird-like dinosaur from the Late Cretaceous period. Found in 1855, it was the first dinosaurs found in North America. Its species ranged widely, with fossil remains recovered from as far north as Alaska and as far south as Wyoming and even possibly Texas and New Mexico.Troodon formosus (from Greek troo - to wound and odon - tooth) was a small possibly maniraptoran theropod dinosaur whose eating habits are still uncertain. This taxon is commonly recognized during excavation from its distinctive small teeth with large denticles along the trailing margin. While the dinosaurs may have ranged upwards to 6 feet (2 meters) in length, many of them must have been the size of chickens or smaller. The teeth size nearby microsites (localities in which most of the fossils are  small, being less than an inch, or 2 cm in length. These fossils are often teeth) are nearly microscopic, ranging upward to a few mm in length. Why the teeth are so small is difficult to understand, unless they are from very young dinosaurs that might have been feasting on the rotting carcasses of Edmontosaurus.

• Found in: North America

• Anatomy: Relatively large brain, large eyes and stereoscopic vision. Lightly built but agile, could run faster than most other dinosaurs of the time. It had excellent co-ordination and vision.

• Length: 2 m

• Height: 1-1.5 m

• Weight (mass): About 40 kg

• Locomotion: Bipedal

• Food preference: Carnivore (small vertebrates, Lizards, mammals)

• Time period: Cretaceous (76-74 million years ago)

• Type of hip: Lizard hipped

• Dinosaur group: Theropod

• Remains: 1982 scientist in Alberta, Canada uncovered the fossilized brain case.

HETERODONTOSAURIDAE

"Heterodontosaurus ("different-teeth lizard") Heterodontosaurids are known only from Lower Jurassic rocks of southern Africa. They were small dinosaurs with a length of 1 to 1.5 meters that had uniquely shaped cheek teeth, chisel-shaped with tiny cusps restricted to the apex of the crown (unique to all dinosaurs). They also had canine-like teeth in the front part of the mouth that had a different shape than the chisel teeth.

1. Heterodontosaurus was 1.2 meters long, with short forelimbs and long hind limbs (considered to be bipedal).
2. Dental battery set in massive lower jaws and the teeth are usually heavily worn (thus a plant eater).
3. Long tail and short neck (typical of primitive ornithischian)
4. Ossified tendons in the back region (along the vertebrae)
5. Fusion of the fibula and tibia and their fusion to the tarsals, this stabilized the lower leg and ankle for fast running (bird-like feature - example of convergent evolution).
6. Hands stout and flexible (perhaps to grasp vegetation)
7. Large canines (tusk like)- may have been used for defense and display (this may be a sexual dimorphic feature, some heterodontosaurid skulls lack canines). The canines may also have helped to stabe and tear vegetation.


8. Bones found in arid paleoenvironments (deserts and arid alluvial fans).

Description

The Heterodontosaurus was a bipedal/quadrupedal dinosaur. Its diet was low-growing plants. It had three kinds of teeth while most dinosaurs only have one type. The names of the three types are sharp upper front teeth, long canine tusks and high-crowned cheek teeth. It had three toes that faced forward on each foot. They had muscular arms and each hand had three large clawed fingers and two small fingers.

Residence

The Heterodontosaurus was 4 feet (1.2m) long and weighed 5.5 pounds (2.5kg). It lived in South Africa Cape, Province and Lesotho Quthing during the late Triassic and early Jurassic Periods

Male and Female

Adult male Heterodontosaurus have sharp canine like teeth that they most likely used to threaten and/or bite other competing males. Females and young males probably did not have those teeth. Their predators included theropods and crocodilians. While running it was probably on two legs and its tail wagged back and forth furiously unlike later ornithopods whose tail would straight. "

HADROSAURIDAE

The Hadrosauridae are commonly known as the duck-billed dinosaurs. They first appeared in Medial Cretaceous time and were the last group of ornithopods to evolve. There is more known about this family than any other group of dinosaurs. Their fossil record includes many complete skeletons, eggs and nests, footprints, and two mummified individuals with skin intact (there are also other fossilized skin impressions of these dinosaurs).

The hadrosaruids were large ornithopods, with lengths of 7 to 10 meters. They had broad, toothless beaks and intricate dental batteries. The dental batteries consisted of hundreds of teeth with a washboard-like grinding surface and three replacement teeth in each tooth position. As in the hyspsilophodontids, they had kinetic jaws such that the upper jaw moved outward and the lower jaw moved inward during chewing. They could process fibrous vegetation, even twigs.

Two mummified hadrosaurids from Canada have stomachs full of conifer needles and twigs, seeds, and other tough plant material. There is very little variation among hadrosaurid skelet

ons, so identification is based on skull structure. There are two major subfamilies based on skull type, the Hadrosaurinae and the Lambeosaruinae

Hadrosaurinae

The hadrosaurines were the more primitive subfamily with rather flat skull roofs or solid crests on the skull. They were large "Roman-nosed" hadrosaurids with long nasals, which often peaked near the posterior end of the nostrils. Examples are Edmontosaurus and Maisauria.

Lambeosaurinae

These were the "crested" duck-bills. They are distinguished by convoluted tubes and crests on the tops of their skulls. The crests contained modified nasal passages and a nasal cavity that was relocated to a position above the orbits. The crests and tubes changed during the growth of individuals, suggesting that sexual dimorphism may have been present. The Upper Cretaceous genera Parasaurolophus and Corythosaurus are representative examples of lambeosaurines.

Short Description

• Like iguanodontids, hadrosaurids were large, strong, quadrapedal walkers, but also could walk on two legs.


• Mummies from Alberta have flaps of skin between fingers, has been suggested that they may have had webbed hands; however, the shrunk and stretched skin from mummification may only make it appear that way.


• They had a tall, paddle-like tail, perhaps for propelling in water.


• Their skeletons are found in river, lake, swamp, deltaic, and sea depositis. Perhaps they were aquatic dinosaurs. But hadrosaurids were also well suited to living on dry land and thus may have entered the water only for feeding or for defensive purposes.


• Had a very wide geographic distribution, known from North America, Asia, Europe, and South America. But they were most abundant and diverse in Asia and North America.


• The hadrosaurids were the dominant plant eating dinosaurs of the Late Cretaceous and they were among the last dinosaurs to become extinct.

HYPSILOPHODONTIDAE

The hysilophodontidae are the most primitive members of Euornithopoda and are a sister group within this clade to Iguandontia (which encompasses all more derivied euornithopods, including the Iguanodontidae and the Hadrosauridae [duck bills]).

Facts

• The hypsilophodontidae were small (2 to 4 meters), bipedal ornithischians that are known from Middle Jurassic to Upper Jurassic rocks of North America, Europe, Asia, and Australia The best known genus is Hypsilophodon


• Bipedal runner, hind limbs much longer than forelimbs.


• Ankle elongate.


• Long tail - stiffened by ossified tendons.


• Skull resembles that of Heterodontasaurus, but does not have the large canine teeth.


• Large eyes.


• Massive jaws, dental battery of interlocking cheek teeth that wore-down to produce a continuous, inclined cutting edge.


• A joint in the skull allowed the upper jaw to move outward over the lower jaw when chewing (a dynamic skull feature).

Hypsilophodonts are well known from complete skeletons and eggs. They were first known from the Middle Jurassic of China, but reached their peak diversity during Late Jurassic to Early Cretaceous. However, they did range to Late Cretaceous.

Two euornithopods that are very similar to the hypsilophodontids, and that may be very close to the evolutionary ancestral stock that links the hypsilophodontids to the iguanodontids, are Tenontosaurus (Lower Cretaceous of North America) and Dryosaurus (Upper Jurassic of North America and Africa).

Both lack premaxillary teeth and had other characters midway between the two groups (Lucas, 1997). However, some prefer to place these two dinosaurs as primitive members of Iguanodontia (which includes all more derived euornithopods above the hpsilophodontidae).

Iguanodon

Iguanodon is best known from Lower Cretaceous rocks of Bernissart, Belgium (where 31 adult skeletons were found in a coal mine at a depth of 321 meters). It is much larger and more specialized than Camptosaurus

Iguanodon had the following characteristics

• Had very long forelimbs (70 to 80% as long as hind limbs).

• The wrist bones were fused (for stable hand walking).

• Central 3 digits of the hand ended in hooves.

• Large conical thumb spike (perhaps a defensive weapon).

• Extensive boxwork of ossified tendons extending along the back vertebrae from the shoulder region to the middle of the tail.

Iguanodon probably did more quadrapedal walking than Camptosaurus or other small ornithopods. But could probably rear up on hind legs and swing its spike-like thumb for defense.

Description of Iguanodontids

• Iguanodontid snouts were long with many more teeth than in heterodontosaurids or hypsilophodontids.

• The beaks were used to crop vegetation.

• Teeth leaf-shaped with long ridges on their sides and small cusps on the cutting edges (resembling teeth of the living iguanas - thus the name for the family).

• Camptosaurus is the oldest iguanodontid and is best known from Upper Jurassic rocks of North America and Europe.

• The zenith of iguanodontid diversity occurred in Early to Medial Cretaceous time in Europe, North America, Africa, Asia, and Australia.

• Iguanodon, Lower Cretaceous of Europe, is the most typical representative of the Iguanodontidae and is the best known genus (with several complete skeletons known).

• A particularly unusual Lower Cretaceous iguanodontid is Ouranosaurus from Niger, Africa, which had a very distinctive head and long neural spines along the back (see page 212 in Fastovsky and Weishampel, 1996).

• There was a marked decline of iguanodontids in Late Cretaceous due (probably) to the appearance of the hadrosaurids (duck-bills).

Eoraptor dinosaur

The Eoraptor lunensis, a medium-sized carnivore found in the Ischigualasto Formation of northwestern Argentina. The find occurs alongside other early dinosaurs and their kin, such as Herrerasaurus and Pisanosaurus.

Eoraptor lacks the specialized features of any of the major groups of dinosaurs, and is quite similar to what would be expected for dinosaur ancestors. This has led some to conclude that it is not part of the dinosaurs proper, but is a closely related archosaur. Others have pointed to the functionally three-fingered hand as an indication of close ties to theropod dinosaurs.

In any case, the traits of Eoraptor suggest that the first dinosaurs were small, bipedal predators. Taken together, the finds at Ischigualasto demonstrate that dinosaurs had radiated by the Late Triassic.

Eoraptor lunensis is roughly the same age as Herrerasaurus - 232 million years old - yet it already shows specialized features which indicate that it lies several branches up from the base of the dinosaurian family tree.

The exact nature of these features suggest that Eoraptor lies at the base of the great Theropoda lineage - the theropod dinosaurs - which includes many celebrity species, such as Tyrannosaurus rex, Allosaurus, Deinonychus, and Velociraptor. .

The upper Triassic Eoraptor is one of the earliest dinosaurs, close to the common dinosaur ancestor. Sereno considers it a primitive theropod, although others consider it a primitive dinosaur or pre-dinosaur.

Attractive features

Foundation- Patagonia, Argentina, South America

Analysis- It had light, hollow bones, a long head with dozens of small, sharp teeth, and five fingers on its hands (two of the fingers on each hand were very small)

Length-1 meter

Height and weight – mass

Locomotion-Bipedal

Food-carnivore

Time period-228 million years

Dinosaur group-Theropod

Dilong paradoxus

Dilong paradoxus-emperor dragon is a primitive, emu-sized tyrannosaur which was covered in feathers. When it lived 130 million years ago.

Description

Dilong paradoxus had a covering of simple feathers or protofeathers. The feathers were seen in fossilized skin impressions from near the jaw and tail. It possessed three fingers on its hands. Growth ring studies indicate that tyrannosaurs grew very quickly when young, supporting warm-bloodedness Dilong paradoxus is a small tyrannosauroid estimated to be 1.6m in body length. The small size of Dilong paradoxus, in comparison with more derived, large tyrannosauroids, Dilong paradoxus shares numerous derived cranial similarities with other tyrannosauroids .

Dilong paradoxus has a less robust skull, a much larger external naris, an expanded braincase, a lower sagittal crest, and anteroposteriorly longer basicranium and a smaller mylohyoid foramen,and lacks a surangular foramen (Fig. 1a–e). Some of these features might be size related; however, progressively larger size is a phylogenetic trend in tyrannosaurids7,9,11. It is also different from other tyrannosauroids in several unique features.

• Discovered country: china

• Eatable-carnivorous

• Weight-73lb

• Length-5.1 feet

Unaysaurus dinosaurs

• It is the oldest dinosaurs known.

• It was discovered in southern Brazil in the geopark of paleorrota, in 1998.


• It is the first meat eating dinosaurs present in South America before 230-250 millions.


• These are the small theropods divided into prosauropods.


• This dinosaur was strongly connected to Plateosaurus, a slightly later (and much more famous) prosauropod of late Triassic Western Europe.


• It is small and walked on two legs.

• It is about 8 feet long.2 feet tall and weighed 200 pounds.


• The main conveyable characteristics are Small size; probably bipedal posture.


• The fossils of Unaysaurus are well conserved. It consists of complete skull, completed with a lower jaw, and partial skeleton with many bones still linked to each other in their usual positions.


• It is one of the most completed dinosaur skeletons, and the most complete skull, ever improved in Brazil.

Allosaurus Dinosaurs

_The carnivorous dinosaur Allosaurus has been known since the late 1800s. This theropod was first documented in 1869.

• Allosaurus fragilis meaning "fragile, different reptile" lived approximately 145-150 million years ago during the Late Jurassic Period, with a recorded geographic range in Wyoming, Montana, Colorado, New Mexico, South Dakota, Utah, Oklahoma and Portugal (Glut, 1997; Prez-Moreno and Chure, 1999).

• It is known to reach 12 meters in length, 4.5 meters in height, and may have weighed up to 2 tons as an adult.

• A fragilis was one of the top predators of its time and is found primarily in the Morrison Formation.

• It lived on the lowland floodplains of the Western Interior in an environment similar to some of the large plains of Africa today (Russell, 1989).

• Allosaurus was the most common large carnivore of the Late Jurassic in North America.

• Strong forelimbs with sharp claws, powerful hind legs and recurved, dagger-like teeth are evidence that Allosaurus was a formidable predator.

• During the Late Jurassic, herds of plant-eating sauropods (such as Apatosaurus) were constantly on the move in search of food to satisfy their large appetites.

• Predators, such as Allosaurus, may have followed these herds, preying on the young and weak.

• Although it was much smaller than the sauropods, quite possibly Allosaurus hunted in packs to bring down larger prey. Like many meat eaters, it may also have been a scavenger.

Balaur (Romanian for "dragon")

Stocky dragon’ roamed Europe'.

It is a specialized species of carnivorous. The fossils are found an off-shore part of the European archipelago called Hațeg Island.

Description

The bones were smaller and weighted than those dromaeosaurs .The feet of the dromaeosaurs single, large. It also possesses a great number of additional autapomorphies, including a reduced and presumably nonfunctional third manual digit. It is one of the apex predators in its island ecosystem. Because there are no larger teeth found in Romania. It uses double sickle claws for slashing prey. However, the hunting behaviors as well as its typical prey are not known.

Habitat: Eastern Europe

Lived: 70-65 million years ago

Size and Weight: 2 feet long and 25 pounds

Diet: Meat

Camptosaurus

The ornithischian dinosaurs during the Cretaceous evolved into a number of interesting groups. From bipedal ornithischians during the Jurassic, like Camptosaurus, the larger and more nimble ornithopods of the Cretaceous evolved. One of the first dinosaurs to be scientifically described was Iguanodon, a bipedal herbivore thought to have moved about in herds. Iguanodon was between 6 and 10 meters long and weighed around 5 tons.

• The Camptosaurus-meaning bent lizard- Lived during the Jurassic era about 150 million years ago.


• It was medium-sized as far as dinosaurs go, weighing about 1,200 pounds and measuring about 23 feet long from head to tail.


• Its head was elongated with tightly-packed blunt teeth in the back of its jaw-evidence of a plant eater.


• In the family Camptosauridae, the toes and fingers ended with small hooflike claws.


• Some had the beginnings of the spiked thumbs that became better developed in the iguanodontids.


• Their teeth were densely packed. Camptosaurus, “bent lizard”, possessed a sharp, horny, toothless beak.


• Camptosaurus had cheeks much like humans. That is they could hold foodstuff in their mouths and chew it like other herbivores-plant eating.


• The Camptosaurus lived in bulky forests secure to rivers. It possibly lived in herds and this would have given it guard from their main meat eating predators, such as the Allosaurus.


• Camptosaurus fossils have been discovered in western North America, Europe, and Australia.


• A complete skeleton was excavated from Dinosaur National Monument in Utah, and fossil evidence of the dinosaur has also been found in Cañon City.

INTERESTING AND IMPORTANT FACT

The dinosaurs was first described by O.C marsh in 1879, but called the dinosaur a Camptonotus. Later the name was changed to Camptosaurus in 1885.

Sauropoda Dinosaur

Sauropoda is among the most diverse and widespread dinosaur lineages, having attained a near-global distribution by the Middle Jurassic that was built on throughout the Cretaceous. These gigantic herbivores are characterized by numerous skeletal specializations that accrued over a 140 million-year history. This fascinating evolutionary history has fuelled interest for more than a century, yet aspects of sauropod interrelationships remain unresolved.

Sauropods were the largest terrestrial vertebrates –their estimated body mass exceeds that of other large dinosaurs by an order of magnitude. Despite the potential biomechanical constraints at this extreme body size, sauropods were the dominant mega herbivorous group throughout 140 million years of the Mesozoic, constituting approximately one-fourth of known dinosaur genera

Description

Sauropods have a distinct, easily recognizable morphology: a long, slender neck and tail at either end of a large body supported by four columnar limbs. The anatomical details of this architecture are unique to sauropods and have furnished the basic evidence of their monophyly

Size

The most central feature was their size. Even the dwarf sauropods like Europasaurus (perhaps 5 to 6 metres) were counted among the biggest animals in their ecosystem. Their only real competitors in terms of size are the Blue Whale. But, sauropods were mainly land-based animals.

Diet

Sauropods were herbivorous (plant-eating)

Muttaburrasaurus

This was a large Ornithopod dinosaur related to Camptosaurus and Iguanodon. It is Australia's known dinosaur from skeletal leftovers. It lived for the duration of some middle Cretaceous period, about 113-97.5 million years ago

Facts

It was an herbivore, with a big beak and razor sharp teeth for shearing tough vegetation.

Muttaburrasaurus had a huge swelling on its lengthy nose between its eyes and its mouth, a beak, a flattened thumb spike, hoof-like claws, and teeth that worked like shears

The skinny bash on its nose may have been connected with its sense of smell or its ability to make sounds

It walked about on all four feet, although it is believed it could run or rear back to eat on its hind legs

Length - 24 feet (7 m) long

Weight - 1-4 tons

Muttaburrasaurus was an herbivore, but may have also eatern some meat. It had crushing teeth. It may have eaten cycads, ferns, and conifers.

This dinosaur is known from fossil remains from Muttaburra, in central Queensland, from the opal fields of Lightning Ridge in western New South Wales, and possibly from Coober Pedy in South Australia

DROMAEOSAURIDAE

Dromaeosaurids are known throughout the Cretaceous and from North and South America, Europe, Asia, Africa, and Madagascar.

Basal dromaeosaurs (Unenlagiinae and Microraptorinae) include some crow- to turkey-sized taxa: Rahonavis of the Late Cretaceous of Madagascar (and initially thought to be a bird); Microraptor of the Early Cretaceous of China (the first eumaniptoran for which the tail feathers were known); long-snouted Buitreraptor of Late Cretaceous Argentina; and others. Not all of these were small, however. One of the most unusual of these basal dromaeosaurids is giant Austroraptor of the mid Late Cretaceous of Argentina: a long-snouted, short-armed polar bear-sized unenlagiine.

The more derived dromaeosaurids (Saurornitholestinae, Deinonychus, Velociraptorinae, and Dromaeosaurinae) form a group called Eudromaeosauria. These were coyote-to-grizzly bear sized. Well-studied examples include coyote-sized Velociraptor of the Late Cretaceous deserts of Mongolia; wolf-sized Deinonychus of the Early Cretaceous of western North America; lion-sized Achillobator of mid-Late Cretaceous Asia; and grizzly-sized Utahraptor of the Early Cretaceous of western North America, at present the largest known eumaniraptoran.

Dromaeosaurid caudals were more tightly interlocked than in typical theropods, and in microraptorines and eudromaeosaurs extensions from the chevrons and neural arches grew extremely long. The tail was thus an extreme dynamic stabilizer.

Some basal dromaeosaurids had elongate metatarsi (indeed, they have a primitive form of the arctometatarsus), but the majority had relatively short stout metatarsi and tibiae. This suggests that they had sacrificed speed, perhaps for agility (better able to turn quickly while pursuing prey or escaping predators, especially with the help of the stiffened tail). Despite certain books and movies to the contrary, the dromaeosaurids show no signs of being speed specialists.

While the small primitive forms may have eaten small prey (skewering it with the sickle claw in the manner of modern secretary birds, perhaps), the larger forms were predators of dinosaurs. The "Fighting Dinosaurs" specimen of Velociraptor shows it in combat with Protoceratops, the hands used to grasp the head of the herbivore while the sickle claw was ripping into the throat: very similar to the attacks used by large cats. Some (contraversial) evidence suggest that Deinonychus may have attacked the much larger iguanodontian Tenontosaurus in groups (packs or mobs).

Note that the sickle claw may have also been used to climb: either up trees, or up the sides of victims! Additionally, they may have been used to pin smaller prey down on the ground while the jaws and hand claws were used to kill it.

At least some of the early forms may have had limited flight capability: indeed, they show somewhat better flight adaptations than Archaeopteryx! The majority of dromaeosaurids, however, probably lived their lives on the ground (although hiding/sleeping in the trees may have been possible, especially for juveniles).

In the Early Cretaceous dromaeosaurids were major mid-sized predators, and in the deserts of Late Cretaceous Asia they were among the largest carnivorous dinosaurs present. However, with the rise of the tyrannosaurids large-bodied dromaeosaurids disappear in the Northern Hemisphere, and the Late Cretaceous dromaeosaurids of Asia and North America were fairly small animals.

Nudibranch

Phylum:Mollusca Class: Gastropoda

Nudibranchia

Nudibranchs are members of the mollusc family; basically they’re snails without a shell.

Description

Nudibranchs are characterised by soft bodies with bright colours and striking patterns to deter predators. They are often called sea slugs. There are more than 3000 species of nudibranchs worldwide! Adults are from 2 to 60 centimetres in length. Nudibranchs have chemical sensors called rhinophores on their head which they use to smell and taste chemicals in the water to help them find food. Nudibranchs have (head) tentacles, which are receptive to handle, flavor, and smell. Club-shaped rhinophores sense odors.

Habitat

It live at all depths of salt water, but reach their greatest size and variation in warm, shallow waters.

Reproduction

It has a set of reproductive organs for both sexes, but they can infrequently fertilize themselves.It naturally drop their eggs inside a jellylike spira

Nudibranchs are hermaphrodites with a set of male and female reproductive organs.

Diet

Most nudibranchs are carnivores, feeding on sponges, hydroids, bryozoans, other sea slug species, or, occasionally they are cannibalistic and prey on members of their own species. Other groups feed on tunicates, barnacles, or anemones.