Why Were Dinosaurs So Big?

The size and the weight of the dinosaurs are huge and no doubt that there have to be reasons for this. Dinosaurs like brachiosaurus and diplodocus were 50 tons in weights, while the fierce T. Rex was 7 to 8 tons. From the remainsof the dinosaurs, we can say that they were gigantic in size and ever since no other living being of this size has ever existed.

There are some theories which talk about the reasons for the dinosaurs to be huge and hefty. The first theory says that the dinosaurs were huge because of the vegetation during that era. In the Mesozoic era, which started with Triassic era and lasted till the Cretaceous era, 65 million years ago, carbon dioxide in the atmosphere was higher when compared to the present times. As the carbon dioxide levels were high, the vegetation provided all kinds of food to the dinosaurs and this excess of food might have made them huge in size. However, this theory does not seem to be realistic enough.

The second theory claims that the hugeness of the dinosaurs must have been a defense mechanism against the predators. To a certain extent this theory seems acceptable as large herbivores flourished and were nearly not preyed upon by predators.

The third theory makes things complicated. Paleontologists who studied dinosaurs say that they were cold blooded based on two reasons. The first reason is related to the metabolism. If the dinosaurs were warm blooded, they would have had internal combustion and died instantaneously. The second reason that the scientists claim is that no modern-day warm blooded mammal living on land comes anywhere close to the size of a dinosaur. Scientists believed that dinos were cold blooded, but when they were large in size, they could regulate their body temperature. So, basically the size of the dinosaur was supposed to be a by-product of being cold blooded. However, this theory does not sit well with all scientists as many claim that dinos were warm blooded and not cold, as suggested by this theory.

Weapons Used by Dinosaurs

When it came to fighting, dinosaurs did not fight like how it is often depicted on the big screen. The reality was quite different. The fights of the dinosaurs can be divided into predator battle and intra-species fight. In the predator battle, the creatures followed 'kill or be killed" rule. And, the intra-species fight was to attract the opposite sex and fight the rival.

Although the dinosaurs did not have weapons like firearms, they were dependent on their natural weapons to get food or mate.

The dinosaur weapons are divided into offensive and defensive weapons. The offensive weapons were teeth and claws which were used by the carnivorous dinosaurs, who lived on herbivores. The defensive weapons like armor plating and tail were used to by the herbivores to defend themselves from the carnivorous dinosaurs.

The offensive weapons of carnivores were primarily teeth, claws, smell and eyesight, momentum, speed and bad breath.

Teeth were used as offensive weapons by T. Rex and allosaurus, whose teeth were neither big nor sharp. They hunted for their food like the cheetahs of today. And, on the basis on analogy of the carnivorous today, the predators of the Jurassic era must have targeted the neck and the belly of the herbivores.

Some dinosaurs like Baryonyx had strong front, while some dinosaurs like Deinonychus and raptors had single curved claw which was rather lengthy. Some of the dinosaurs like troodon had big eyes to see things at far off places which helped them in hunting for the food. Some were able to smell the herbivores which were at distant places.

Momentum was the weapon of tyrannosaurs which hunted with a force that made it difficult for an herbivore to escape. The speed at which the raptors attacked the herbivores was a weapon also. Paleontologists say that the tyrannosaurs teeth had bacteria which would fatally infect the prey. Once the prey died, the tyrannosaurus would consume the prey.

Are You a Leader Or a Dinosaur?

During my studies at Duquesne University, I recall the age old disputes we had about whether "leaders were born - or made." Our discussions were insightful and always lively. Frequently, our points of view ranged from one end of the spectrum to the other. A large cup of coffee, a note pad, and an open mind were among the things I always brought to class.

Are leaders born with particular genetic traits - or are they shaped by their environment? That's the question. Figuratively speaking, we start-off as "soft clay." And over time, we're shaped and formed by many different experiences. Eventually, we become fixed in place like a piece of hard clay.

But it doesn't stop there - because a person's upbringing has impact, too. Just as a good cook adds different ingredients to prepare a meal, leaders are made the same way. They encounter all kinds of experiences, both good and bad. These events shape them in different ways. Even the customs of a big city can shape a leader. Pittsburgh was once known as the "Steel City." It was like a big dinosaur that could wag its tail and send contenders scampering.

As competition increased, the Steel City lost its swagger. It was cheaper to order steel from Japan versus the plant right across the river. Clearly, the steel industry was changing and Pittsburgh had to change, too. If we didn't, the city would literally become extinct like a dinosaur. Today, Pittsburgh is a symbol of transformation. It's eco-friendly and green, a leader in healthcare and well-known for cutting edge technology.

So what's the connection between the Steel City, dinosaurs, and modern day leadership? Well, the old leadership model was very straight-forward. Managers used to say, "I'm the boss - it's my way or the highway." They were like dinosaurs. But over the last decade, I saw a transformation happen. Our workforce began to change. The demand for leaders increased as our need for managers faded away. A younger more educated generation came on the scene. And the old model of leadership became a thing of the past.

In most organizations, the days of absolute power are long gone. Because the source of power has drastically changed. Companies are smarter, and they recognize the benefits of tapping into their human assets. Organizations have become flatter in order to achieve faster results. In other words, the speed at which you can move a product to market determines success - providing of course, the product is high quality.

Today, leaders have to be visionary and open to new ideas. They also have to understand that good ideas sometimes come from the bottom-up, and not necessarily top-down. It's all about optimizing resources and market differentiation. Leaders need to be resilient. It's critical that they have the ability to bounce back.

Speaking of resilience, I was as pathetic a baseball player as you can imagine. In little league, I once made all three outs in the same inning. We beat the opposing team 45-0. As expected, the coach cut me from the team. I was very disappointed in my performance and kept practicing on my own. Despite being cut from the team, I showed-up everyday to watch them practice.

The head coach said "Isn't that the guy we cut last week?" Yup, the other coach said - that's the fellow. He's here everyday before everyone else. The head coach said, "Really - well if the boy's that persistent, give him a uniform and sit him on the bench." By the end of the summer, I was a star player with a great batting average. Here's my point; if you want to be an effective leader, you have to be able to bounce back.

Sometimes we're victims of our past. I remember another situation, when a guy described how he asked a manager for help on a project. The manager's lip started to quiver, his eyes turned beet red and he yelled "I gave you all the help you're gonna get - now make it happen!" Needless to say, that poor guy was convinced his manager was a born tyrant. It made him cynical. But sadder still, this guy was his mentor. And he had taken on some of the same traits. He had become a tyrant, too.

He was convinced a strong leader had to "knock some heads" to gain respect. A few years later, I saw him on the street. He said "I learned a lesson the hard way. I got fired. My hard-nose attitude got me in trouble." Basically, he tried to hold on to some primitive ways in changing times. More importantly, he tried to hold on to his respect as a leader - but he couldn't.

I said, it's up to you to change that image. Don't become a victim of your past. You can still grow as a leader. Admit your faults and apologize to the people you offended. Don't let the phantoms of your past haunt you. I further explained how leaders ought to be resilient. They need to be able to bounce back. Learn from your mistakes. You don't have to be a manager to be a leader, I said. However, you do have to treat people with respect and speak to them with dignity. Give others the same courtesy that you want. Remember, the dinosaur is extinct... and their ways are, too.

Bottom line; "Leaders are made - not born!" They're shaped by their experiences, both good and bad. They are resilient and able to bounce back. Unlike the dinosaur, effective leaders learn from their mistakes. Stay flexible, be open to change - and be a continuous learner.

Camping With the Dinosaurs in Dinosaur Provincial Park in Alberta

Nestled amongst the sagebrush some 50 km NE of Brooks, Alberta lies a striking example of Mother Natures power as well as one of her best kept secrets (until the last century that is) in the form of one of the worlds richest deposits of dinosaur bones.

Dinosaur Provincial Park campground offers campers the unique experience of going back in time and camping where dinosaurs lived some 75 million years ago.

The park is now home to a wide variety of animals (Coyotes, Porcupines, Pheasants, Pronghorn Antelope, Snakes, Hawks, and Owls) and during your stay you are almost guaranteed to encounter a great many of them.

The park was established in 1966 in order to protect its rich deposits of dinosaur fossils and diverse ecosystems of prairie grasslands, "badlands" and riverside cottonwood trees. In 1979 it became a UNESCO World Heritage Site. So rich is this land in dinosaur fossils, they are to this day being unearthed by the rain which simply washes them out of the banks of the hoodoos or rock formations carved from the land by the wind and rain.

There is a wide variety of interpretive programs, including guided and self guided hikes and two outdoor fossil exhibits available. No trip to Dinosaur Provincial Park would be complete without a visit to the interpretative centre which has been revamped recently and is spectacular! The kids will love it.

The campground itself is located in the river valley on either side of the Little Sandhill Creek that empties into the Red Deer River. Most of the 126 campsites are scattered amongst the Cottonwood trees native to the area, with a few under the area known as the Badlands Slopes or hoodoos that can become excruciatingly hot during the Summer months. About half of the campsites have power. Also available is a 10 unit group campsite facility complete with its own cookhouse.

Because of the low lying location of this campground, in July of 2009 during a torrential downpour the valley was flooded and campers were forced to evacuate. The campground has since been largely rebuilt but the storms effects are still noticeable. After surveying the remaining flood damage one can get a true sense of how powerful the forces that formed this areas rock formations were.

The campground is open year round. Campsites are reserved through either the online reservation system or through their toll free line at 1-877-577-2737 mid May through early September or on a first come first serve basis the remainder of the year. Campground services are limited during the off season.

Camping with the dinosaurs makes this one of our kids' most popular campgrounds. Be sure to add it to your list of must see campgrounds!

Creationism Vs Evolution - Did Dinosaurs Live Among Us?

Young earth creationists believe that the world was created only a few thousand years ago. While many paleontologists argue that carbon dating indicates that life had existed over a million years ago, there is reason to speculate that this is untrue.

If the Earth is merely thousands (and not millions) of years old, what does this mean in regards to the existence of dinosaurs? More specifically, what does this mean in regards to the existence of dinosaurs as it relates to the human species? Could the dinosaurs have lived among us? Some findings suggest this could have been the case.

The term "dinosaur" has only existed since 1842 when it was first coined by English paleontologist Richard Owen, yet their existence had been acknowledged in writing centuries previous to this. Sometime between the 8th and 11th centuries, a poem was written about the Scandinavian king, Beowulf.. In the poem, the writer gives a detailed description about a beast that the king had killed in battle. If you look at the description, it accurately describes the appearance of a Tyrannosaurus Rex. Since paleontology had only existed since the 18th century as a result of Georges Cuvier's work on comparative anatomy, how is it possible that the author could so accurately describe a creature he should know nothing about?

The written word is not the only place where dinosaurs are mentioned. Aboriginal legends have been passed from one generation to another by word of mouth. One such legend exists among the Native American tribes about the "thunderbirds". According to the legend, large bird-like creatures flew around and they would bring thunder with them wherever they went. In South Dakota, the Native American groups have pointed to pteranodon fossils located at the base of the Black Hills and referred to them as thunderbirds. Had pteradons flown past the aboriginals centuries ago, or is this a mere coincidence?

One of the most compelling arguments relates to the processes used among the paleontologists. Arguments have been made that because of carbon-dating, paleontologists can accurately estimate when a species lived and when it no longer existed, however this isn't always the case. It was thought that the Coelacanth had been extinct since the end of the Cretaceous period. However, when the species resurfaced in 1938, many were baffled. If a species thought to have died out millions of years ago could still exist, how could we be so certain that dinosaurs never lived among us?

Tyrannosaurus Rex

Name:
Tyrannosaurus Rex (Greek for "tyrant lizard king"); pronounced tih-RAN-oh-SORE-us REX
Habitat:
Forests and swamps of North America
Historical Period:
Late Cretaceous (70-65 million years ago)
Size and Weight:
About 40 feet long and 7 tons
Diet:
Other dinosaurs
Distinguishing Characteristics:
Large head with numerous teeth; stubby, almost vestigial arms
About Tyrannosaurus Rex:

Tyrannosaurus Rex is by far the most popular of all dinosaurs, spawning a huge number of books, movies, TV shows and video games. What's truly amazing, though, is how much about this carnivore that was once assumed as fact has lately been called into question. (See more facts, figures and news about Tyrannosaurus Rex, as well as a gallery of Tyrannosaurus Rex pictures and 10 Facts About T. Rex.)

For example, one controversy that's currently making the rounds among paleontologists is whether T. Rex was a hunter or scavenger. Some experts think T. Rex feasted on already dead prey, on the premise that it couldn't have been fast enough or smart enough to hunt down other dinosaurs--but it was equipped with features (such as a superior sense of smell) that are found in modern scavengers, like vultures. In another development, it's now believed that T. Rex individuals may have succumbed to trichomonosis, a parasitic disease that affects modern birds, and it's entirely possible that T. Rex juveniles were covered in downy coats of feathers, at least to judge by another genus of tyrannosaur, the Asian Dilong.

Despite how it's depicted in action movies, we don't know for sure how speedy Tyrannosaurus Rex was. Unlike the juggernaut of the Jurassic Park movies, it's possible that this dinosaur lumbered along at a poky 10 miles per hour, max--meaning a hungry female would have found it hard to outrun a kid on a bicycle! (For the record, other theropods of the late Cretaceous period, notably the ornithomimids, were capable of sprinting at a zippy 50 miles per hour or so.)

Shonisaurus

Name:
Shonisaurus (Greek for "Shoshone mountain reptile"); pronounced show-nih-SORE-us
Habitat:
Oceans worldwide
Historical Period:
Late Triassic (225-208 million years ago)
Size and Weight:
About 50 feet long and 30 tons
Diet:
Fish, squid and cephalopods
Distinguishing Characteristics:
Large, thick trunk; large eyes; sharp teeth
About Shonisaurus:

Shonisaurus was among the strangest of all ichthyosaurs ("fish lizards"), looking a bit like a cross between a dolphin and a whale with its thick, round body, long, narrow front and rear flippers, pointed mouth with teeth only on the front end, and double-pronged tail. At upwards of 50 feet long and 30 tons, this was one of the biggest animals on the planet during the late Triassic period, matched in size only by the giant marine reptiles and fish that lived tens of millions of years later, notably Liopleurodon and Leedsichthys.

Like other ichthyosaurs, Shonisaurus is believed to have evolved from land-dwelling lizards that returned to an aquatic lifestyle during the early Triassic period. That makes this family of marine reptiles roughly analogous to modern dolphins and whales, which also evolved from smaller, land-dwelling ancestors. (By the way, Shonisaurus is the state fossil of land-locked Nevada, which was submerged beneath a shallow body of water during much of the Mesozoic Era.)

Moschops

Name:
Moschops (Greek for "calf face"); pronounced MOE-shops
Habitat:
Forests of South Africa
Historical Period:
Late Permian (255 million years ago)
Size and Weight:
About 16 feet long and one ton
Diet:
Plants
Distinguishing Characteristics:
Thick skull; short tail; front legs longer than hind legs
About Moschops:

Moschops is a case study in how evolution produces roughly the same forms to occupy the same ecological niches. Although it was a therapsid (mammal-like reptile) rather than a true dinosaur, Moschops was markedly similar to later ornithopods and hadrosaurs like Iguanodon and Maiasaura: thick-set, medium-sized, and built close to the ground, the better to browse on low-lying vegetation. In an important sense, though, Moschops was the less "evolved" reptile, since it had a classic, splay-footed reptilian posture and (if it was possible) an even tinier brain. (By the way, the family of mammal-like reptiles to which Moschops belong went on to spawn the earliest true mammals during the Triassic period.

It may seem hard to believe, but Moschops was the star of a short-lived kids' TV show back in 1983, though it's unclear whether the producers knew that it technically wasn't a dinosaur. Granted, that wasn't the only scientific inaccuracy: for example, Moschops shared a cave with his best friend, an Allosaurus, and his grandfather was a Diplodocus. Perhaps it was a good thing that Moschops only lasted for 13 episodes before fading into pop-culture obscurity.

Quetzalcoatlus

Name:
Quetzalcoatlus (named after the Aztec god Quetzalcoatl); pronounced KWET-zal-co-AT-lus
Habitat:
Skies of North America
Historical Period:
Late Cretaceous (80-65 million years ago)
Size and Weight:
Wingspan of 30 feet and 200 pounds
Diet:
Fish and meat
Distinguishing Characteristics:
Large size; narrow wings; long, pointed beak
About Quetzalcoatlus:

Almost certainly the largest creature--whether bird, insect, mammal or reptile--ever to take to the air, Quetzalcoatlus did credit to the fearsome Aztec god after which it was named. The most impressive species of this giant pterosaur attained wingspans of over 30 feet, and must have been greatly feared by terrestrial critters when they soared down from the sky in search of food. Right? Well, maybe not: a recent analyis of Quetzalcoatlus' anatomy hints that this pterosaur may have led a completely terrestrial existence, stalking its prey on two legs like the contemporary raptors and tyrannosaurs of the late Cretaceous period. (See a gallery of Quetzalcoatlus pictures.)

The fact is, paleontologists are still trying to piece together exactly how Quetzalcoatlus lived. It's generally agreed that, if this reptile indeed flew, it glided rather than flapped its wings, which given its size and presumed cold-blooded metabolism would likely have been an anatomical impossibility. Even less certain is how Quetzaloatlus fed; it may have scavenged already-dead carcasses like a vulture, gobbled down fish like a stork, or plucked out unfortunate fish, plesiosaurs and mosasaurs as it skimmed close to the North American shoreline.

As big as it was, Quetzalcoatlus wasn't the only plus-sized pterosaur of the Mesozoic Era, though it vastly outweighed its nearest relatives. The next biggest pterosaur on the block was probably Ornithocheirus, and a pair of genera from South America, Tapejara and Tupuxuara, also cut impressive profiles (and were probably brightly colored as well; we know virtually nothing about how Quetzalcoatlus might have looked at the height of the mating season).

Spinosaurus

Name:
Spinosaurus (Greek for "spine lizard"); pronounced SPINE-oh-SORE-us
Habitat:
Swamps of North Africa
Historical Period:
Middle Cretaceous (95 million years ago)
Size and Weight:
About 50 feet long and 7 tons
Diet:
Meat and fish
Distinguishing Characteristics:
Long, spiky protuberances from vertebrae supporting a "sail" of skin
About Spinosaurus:

If it weren't for one tell-all feature, Spinosaurus might have been indistinguishable from any other large theropod stalking the swamps of the Cretaceous period. That feature, of course, was the extensive, fin-shaped sail on its back, a thin flap of skin supported by sharp needles of bone that protruded from Spinosaurus' vertebrae. (See more facts, figures and news about Spinosaurus, 10 Facts About Spinosaurus and a gallery of Spinosaurus pictures.)

Why did Spinosaurus have this strange-looking sail? The most likely explanation is that this structure evolved for cooling purposes in the hot northern African climate in which Spinosaurus lived (a bit like the big, floppy ears of African elephants). It may also, as a byproduct, have been a sexually selected characteristic--perhaps male Spinosaurus with bigger sails had more success mating with females.

By the way, paleontologists now believe that Spinosaurus was the largest carnivore that ever lived--outclassing even Tyrannosaurus Rex by one or two tons. Fortunately--or unfortunately, if you happen to be a movie producer--these two dinosaurs didn't share the same time or territory, T. Rex living tens of millions of years later in North, rather than South, America.

Albertosaurus

Name:
Albertosaurus (Greek for "Alberta lizard"); pronounced al-BERT-oh-SORE-us
Habitat:
Forests of western North America
Historical Epoch:
Late Cretaceous (75 million years ago)
Size and Weight:
About 30 feet long and 3 tons
Diet:
Herbivorous dinosaurs
Distinguishing Characteristics:
Large head with numerous teeth; powerful hind legs; short arms
About Albertosaurus:

As carnivorous dinosaurs go, Albertosaurus is fairly well known, with multiple, more-or-less complete fossils of this famous tyrannosaur having been dug up in North America (many in the Canadian province of Alberta, after which the genus is named).

For all intents and purposes, Albertosaurus can be considered a slightly smaller version of Tyrannosaurus Rex, "only" about three tons (compared to more than twice that for the largest T. Rex individuals) but every bit as dangerous. This tyrannosaur made its living by hunting the numerous herbivorous dinosaurs of the late Cretaceous period, probably making a specialty out of slow-witted hadrosaurs.

Scarily, paleontologists have found traces of evidence that Albertosaurus may have hunted in packs. If this is true, then it's likely that not even the armored, full-grown herbivores of Cretaceous North America (such as Triceratops) were truly safe from being turned into a quick lunch.

Colepiocephale

Name:
Colepiocephale (Greek for "knucklehead"); pronounced co-LEE-pee-oh-SEF-ah-lee
Habitat:
Woodlands of North America
Historical Period:
Late Cretaceous (75-70 million years ago)
Size and Weight:
About 3 feet long and 10-15 pounds
Diet:
Plants
Distinguishing Characteristics:
Small size; flat, sloped skull
About Colepiocephale:

There's one thing you can say about the paleontologist who discovered Colepiocephale: he or she had a good sense of humor. In true Three Stooges style, this tiny herbivore's name is Greek for "knucklehead," as befits your typical pachycephalosaur (or bone-headed dinosaur).

Its odd name aside, Colepiocephale is important for being one of the earliest boneheads discovered to date in North America (Asian pachycephalosaurs, such as Goyocephale, appear to have predated their American cousins by a few million years). Colepiocephale also had an unusual skull compared to other dinosaurs of its kind; it wasn't domed or especially thick, but flat, sloped and roughly triangular.

Titanophoneus

Name:
Titanophoneus (Greek for "titanic murderer"); pronounced tie-TAN-oh-PHONE-ee-us
Habitat:
Woodlands of central Asia
Historical Period:
Late Permian (255-250 million years ago)
Size and Weight:
About 8 feet long and 200 pounds
Diet:
Meat
Distinguishing Characteristics:
Long tail and head; short, sprawling legs
About Titanophoneus:

As therapsids, or mammal-like reptiles, go, Titanophoneus has been a bit oversold by paleontologists. True, this "titanic murderer" was probably dangerous to other therapsids of the late Permian period, but it must have been positively harmless compared to the bigger raptors and tyrannosaurs that lived almost 200 million years later.

Probably the most advanced feature of Titanophoneus was its teeth: two dagger-like canines in front, accompanied by sharp incisors and flat molars in back for grinding up flesh. As with other mammal-like reptiles--which went on to spawn the first true mammals of the late Triassic period--it's possible that Titanophoneus was covered in fur and had a warm-blooded metabolism, though we may never know for sure.

Micropachycephalosaurus

Name:
Micropachycephalosaurus (Greek for "tiny thick-headed lizard"); pronounced MY-cro-PACK-ee-SEFF-ah-low-SORE-us
Habitat:
Woodlands of Asia
Historical Period:
Late Cretaceous (80-70 million years ago)
Size and Weight:
About 2 feet long and 5-10 pounds
Diet:
Plants
Distinguishing Characteristics:
Small size; thick skull
About Micropachycephalosaurus:

The name Micropachycephalosaurus may seem like a mouthful, but it's not so bad if you break it down into its constituent Greek words: micro, pachy, cephalo, saurus. That translates into "tiny thick-headed lizard," and fittingly, Micropachycephalosaurus is the smallest of all the known pachycephalosaurs (otherwise known as boneheads). For the record, the dinosaur with the shortest name--Mei--was also bite-sized; make of that what you will!

Because Micropachycephalosaurus has been reconstructed from incomplete remains dug up in China, the possibility looms that this genus may one day be "downgraded"--that is, paleontologists will agree that it's another type of pachycephalosaur entirely (recently, experts figured out that the shape of pachycephalosaur skulls changed as these dinosaurs aged, makes classification mistakes all the more likely). If that happens, some other multisyllabic dinosaur (possibly Brachytrachelopan) will rise up to assume the "world's longest name" title.

Irritator

Name:
Irritator; pronounced IH-rih-tay-tore
Habitat:
Lakesides of South America
Historical Period:
Middle Cretaceous (100 million years ago)
Size and Weight:
About 25 feet long and one ton
Diet:
Meat
Distinguishing Characteristics:
Long, narrow skull; spines along back
About Irritator:

As spinosaurs--large, carnivorous dinosaurs with crocodile-like heads and jaws--go, Irritator wasn't any more "irritating" than any other genus. Rather, this predator acquired its name because its only existing skull had been touched up with plaster by an overeager fossil hunter, requiring paleontologist Dave Martill to spend long, tedious hours undoing the damage.

As you may already have guessed, Irritator was closely related to its fellow South American theropod Spinosaurus, the biggest carnivorous dinosaur that ever lived--and it may yet wind up being assigned as a species of yet another South American spinosaur, Angaturama. By the way, the last name of the only known species of Irritator is "challengeri," after the lead character in Sir Arthur Conan Doyle's novel The Lost World.

Gigantoraptor

Name:
Gigantoraptor (Greek for "giant thief"); pronounced gee-GAN-toe-rap-tore
Habitat:
Plains of Central Asia
Historical Period:
Late Cretaceous (85 million years ago)
Size and Weight:
About 25 feet long and 2 tons
Diet:
Probably omnivorous
Distinguishing Characteristics:
Large size; probably feathers
About Gigantoraptor:
Despite its scary name, it's important to realize that Gigantoraptor wasn't technically a true raptor, like Deinonychus, Velociraptor or the equally huge Utahraptor. Rather, this large, feathered theropod was a close relative of Oviraptor, and the largest such "dino-bird" yet discovered. Gigantoraptor was "diagnosed" based on a single, incomplete skeleton found in Mongolia in 2005, so further discoveries may shed some much-needed light on its lifestyle (such as whether it contented itself with a herbivorous diet, like other oviraptors, or occasionally supplemented its leafy greens by hunting smaller dinosaurs).

How Dinosaurs Are Named

Most of the time, paleontology is an anonymous and not terribly exciting occupation--the typical PhD candidate spends most of her day laboriously removing encrusted dirt from newly discovered fossils. The one chance a researcher really gets to shine is when he or she discovers--and gets to name--a new type of dinosaur.

There are all sorts of ways to name a dinosaur. Some of the most famous dinos are named after prominent anatomical features (e.g., Triceratops, which means "three-horned head") while other are named according to their supposed behavior (the most famous example is Oviraptor, which means "egg thief"). A bit less imaginatively, some dinosaurs are named after the places their fossils were unearthed--witness the Canadian Edmontosaurus.
Generally, dinosaurs are referred to by their genus--the next step up the taxonomic tree from an individual species. For example, the dinosaur commonly known as Ceratosaurus comes in four different flavors: nasicornus, dentisulcatus, ingens and roechlingi. Most people can get by with just saying "Ceratosaurus," but scientists refer more precisely to the spcies Ceratosaurus ingens (the whole name is italicized, with only the genus name capitalized).
"Deprecated" Dinosaurs
According to the arcane (but eminently fair) rules of paleontology, a dinosaur's first official name is the one that counts. That is, if a paleontologist digs up a unique dinosaur in South America, his name is the one that sticks, even if an identical species is found and named a week later (before the first researcher had a chance to publicize his discovery).

Occasionally, this strict rule can lead to some confusion. The most famous example is Apatosaurus, which is now the "correct" name for the sauropod once known as Brontosaurus. It turns out that the same famous paleontologist who discovered (and named) the bones of Apatosaurus later discovered (and named) the bones of what he thought was an entirely different dinosaur. When it turned out that Brontosaurus was the same animal as Apatosaurus, official rights reverted back to the original name, leaving Brontosaurus as what paleontologists call a "deprecated" genus.
"People"-saurs

Surprisingly, fairly few dinosaurs are named after people, perhaps because paleontology tends to be a group effort. Some legendary practitioners, though, have been honored in dinosaur form: for example, Othnielia is named after the famous paleontologist Othniel C. Marsh (the same scientist who caused the whole Apatosaurus/Brontosaurus blowup), while the dino dubbed Drinker wasn't a primitive alcoholic, but named after the 19th-century fossil hunter Edward Drinker Cope.

Perhaps the most widely publicized people-saur of modern times is Leaellynosaura, which was discovered by a married pair of paleontologists in Australia in 1989. They decided to name this small, gentle herbivore after their young daughter, the first time a child has ever been honored in dinosaur form!

Sauropods: The Biggest Dinosaurs

Sauropod Paleontology

It's one of the paradoxes of modern paleontology that the largest animals that ever lived left the most incomplete skeletons. While bite-sized dinosaurs like Microraptor tend to fossilize all in one piece, complete sauropod skeletons are rare on the ground. Further complicating matters, sauropod fossils are often found without their heads, because of an anatomical quirk in how these dinosaurs' skulls were attached to their necks (so their skeletons are easily "disarticulated," as the term goes.

The jigsaw-puzzle-like nature of sauropod fossils has tempted paleontologists into a fair number of blind alleys. Often, a gigantic tibia will be advertised as belonging to an entirely new genus of sauropod, until it's discovered (based on more complete analysis) to belong to a plain old Cetiosaurus. (This is the reason the sauropod once known as Brontosaurus is today called Apatosaurus: Apatosaurus was named first, and the dinosaur subsquently called Brontosaurus turned out to be a, well, you know.) Even today, some sauropods linger under a cloud of suspicion; many experts believe Seismosaurus was really an unusually big Diplodocus, and proposed genera like Ultrasauros have been discredited altogether.

This confusion about sauropod fossils has also resulted in some famous confusion about sauropod behavior. When the first sauropod bones were discovered, well over one hundred years ago, paleontologists believed they belonged to ancient whales--and for a few decades, it was fashionable to picture Brachiosaurus as a semi-aquatic creature that roved lake bottoms and stuck its head out of the surface to breathe!

Here's an alphabetical list of the 20 most notable sauropod genera; just click on the links for more details.

Apatosaurus The dinosaur formerly known as Brontosaurus.

Argentinosaurus Possibly the largest herbivore that ever lived.

Barapasaurus Probably the first of the giant sauropods.

Barosaurus An enormous plant-eater with a tiny head.

Brachiosaurus A giant, gentle, long-necked plant-eater.

Brachytrachelopan This sauropod had an unusually short neck.

Camarasaurus The most common sauropod of Jurassic North America.

Cetiosaurus Guess which creature this "whale lizard" was once mistaken for?

Diplodocus "Thin at one end, much thicker in the middle, and thin again at the far end."

Europasaurus The smallest sauropod ever discovered.

Mamenchisaurus The longest-necked dinosaur that ever lived.

Paralititan This huge sauropod was discovered recently in Egypt.

Rapetosaurus The only sauropod ever to be discovered on modern-day Madagascar.

Saltasaurus The first armored sauropod ever to be discovered.

Sauroposeidon One of the tallest dinosaurs ever to walk the earth.

Seismosaurus It was huge, to be sure--but might it have been a species of Diplodocus?

Shunosaurus Anatomically speaking, probably the best known of all the sauropods.

Supersaurus No, it didn't wear a cape--but this giant dino was still impressive.

Titanosaurus This sauropod may--or may not--have been a unique member of its genus.

Vulcanodon An early sauropod of the Jurassic period.

Sauropods: The Biggest Dinosaurs that Ever Lived

Think of the word "dinosaur," and two images are likely to come to mind: a snarling Velociraptor hunting for grub, or a giant, gentle, long-necked Brachiosaurus lazily plucking the leaves off trees. In many ways, the sauropods (of which Brachiosaurus was a prominent example) are more fascinating than bipedal predators like T. Rex or Velociraptor. By far the largest creatures ever to roam the earth, sauropods branched into numerous genera and species over the course of 100 million years, and their remains have been dug up on every continent, including Antarctica. (See a gallery of sauropod pictures.)

So what, exactly, is a sauropod? Some technical details aside, paleontologists use the term to describe large, four-legged, plant-eating dinosaurs with bulky bodies, long necks and tails, and tiny heads with small brains (in fact, sauropods are believed to have been the dumbest of all the dinosaurs, with the smallest "encephalization quotient"). The name "sauropod" itself is Greek for "lizard foot," which oddly enough was among these dinosaurs' least distinctive traits!

As with any broad definition, though, there are some important "buts" and "howevers." Not all sauropods had long necks (witness the oddly truncated Brachytrachelopan), and not all were the size of houses (one recent discovery, Europasaurus, seems to have only been about the size of a large ox). On the whole, though, most classical sauropods--familiar beasts like Diplodocus and Apatosaurus (the dinosaur previously known as Brontosaurus)--follow the sauropod body plan to the letter.
Sauropod Evolution

According to current knowledge, the first true sauropods (such as Vulcanodon and Barapasaurus) arose about 200 million years ago, in the early to middle Jurassic. The exact evolutionary relationships are unclear, but it's possible that these huge herbivores were directly descended from smaller "prosauropods" like Anchisaurus and Massospondylus.

The sauropods reached the peak of their eminence toward the end of the Jurassic period, 150 million years ago. Fully grown adults had a relatively easy ride, since they were virtually immune to predation (although it's possible that packs of Allosaurus might have ganged up on an adult Diplodocus), and the steamy, vegetation-choked jungles covering most of the Jurassic continents provided a constant supply of food.

The Cretaceous period saw a slow slide in sauropods' fortunes; by the time the dinosaurs went extinct 65 million years ago, only the titanosaurs (such as Titanosaurus and Rapetosaurus) were left. Frustratingly, while paleontologists have identified dozens of genera of titanosaur, the lack of fully articulated fossils and the rarity of intact skulls means that much about these beasts is still shrouded in mystery. We do know, however, that many titanosaurs had rudimentary armor plating--clearly an evolutionary adaptation to predation by carnivores.
Sauropod Behavior and Physiology

As befitted their size, sauropods were eating machines: an adult had to scarf down hundreds of pounds of plants and leaves every day. Depending on their diets, sauropods came equipped with two basic kinds of teeth: either flat and spoon-shaped (as in Camarasaurus and Brachiosaurus), or thin and peglike (as in Diplodocus). Presumably, the spoon-toothed sauropods subsisted on tougher vegetation that required more powerful grinding and chewing.

Reasoning by analogy with modern giraffes, most paleontologists believe sauropods evolved their ultra-long necks in order to reach high leaves. However, this raises as many questions as it answers, since pumping blood to a height of 40 or 50 feet would strain even the most robust heart. One maverick has suggested that the necks of some sauropods contained strings of "auxiliary" hearts, but lacking solid fossil evidence, few experts are convinced.

This brings us to the question of whether sauropods were warm-blooded. Generally, even the most ardent advocates of warm-blooded dinosaurs back off when it comes to sauropods, since simulations show that these oversized animals would have baked themselves from the inside, like potatoes, if they generated too much metabolic energy. Today, the prevalence of opinion is that sauropods were cold-blooded homeotherms--that is, they managed to maintain a near-constant body temperature because they warmed up very slowly and cooled off equally slowly.

Next Page: Sauropod Paleontology, and a List of Major genera

Titanosaurs - The Last of the Sauropods

By the beginning of the Cretaceous period, about 140 million years ago, gigantic herbivores like Diplodocus and Brachiosaurus were on the decline. However, this didn't mean that sauropods as a whole were destined for early extinction; an offshoot of these huge, four-footed plant-eaters, known as titanosaurs, continued to prosper right up to the K/T Extinction 65 million years ago. (See a gallery of titanosaur pictures.)

The problem with titanosaurs--from a paleontologist's point of view--is that their fossils tend to be scattered and incomplete, much more so than for any other family of dinosaurs. Very few articulated skeletons of titanosaurs have been found, and virtually no intact skulls, so reconstructing what these beasts looked like has required a lot of guesswork. Fortunately, their close similarity to earlier sauropods, their wide geographic distribution (titanosaur bones have been found on every continent except Australia), and their extensive number of genera (possible as many as 100) has made it possible to hazard some reasonable theories.
Titanosaur Characteristics

As stated above, titanosaurs were very similar in build to earlier sauropods: they were quadrupedal, long-necked and long-tailed, and tended toward enormous sizes (one of the biggest titanosaurs, Argentinosaurus, may have reached lengths of 100 feet, though genera like Saltasaurus were considerably smaller). What set titanosaurs apart from the pack were subtle anatomical differences involving their skulls and bones, and, most famously, their rudimentary armor: it's believed that most, if not all, titanosaurs had tough, bony plates covering their bodies.

This last feature raises an interesting question: could it be that earlier sauropods perished at the end of the Jurassic period because their juveniles were preyed on by carnivorous dinosaurs? If so, the development of titanosaur armor (even though it wasn't nearly as ornate or dangerous as the armor found on ankylosaurs) might have been a key evolutionary adaptation that allowed these gentle herbivores to survive.
Titanosaur Habitats & Behavior

Despite their limited fossil remains, titanosaurs were clearly some of the most successful dinosaurs ever to walk the earth. In the Cretaceous period, most other types of dinosaurs were restricted to certain geographic areas--pachycephalosaurs in North America and Asia, for example--but titanosaurs attained worldwide distribution. There may, however, have been stretches of millions of years when titanosaurs were clustered on the southern supercontinent Gondwana (which is where Gondwanatitan gets its name); more titanosaurs have been discovered in South America than on any other continent.

Paleontologists know about as much about the everyday behavior of titanosaurs as they do about the everyday behavior of sauropods in general--which is to say, not a whole lot. There's evidence that some titanosaur genera may have roamed in herds of dozens or hundreds of adults and juveniles, and the discovery of nesting grounds (complete with fossilized eggs) hints that females may have laid their eggs in groups, to better protect their young.
Titanosaur Classification

Moreso than with other types of dinosaurs, the classification of titanosaurs is a matter of ongoing dispute: some paleontologists think "titanosaur" isn't a very useful designation, and prefer to refer to smaller, anatomically similar, and more manageable groups like "saltasauridae" or "nemegtosauridae."

The doubtful status of titanosaurs is best exemplified by its eponymous genus, Titanosaurus. Over the years, Titanosaurus has become a kind of wastebasket genus to which poorly understood fossil remains have been assigned (meaning that many of the species assigned to this genus may not actually belong there!).

Classification controversies aside, here's a list of the most notable titanosaur genera; just click on the links for more information.

Aegyptosaurus Guess what country this dinosaur was found in?

Alamosaurus No, it wasn't named after the Alamo, but it should have been.

Ampelosaurus One of the best-known of the armored titanosaurs.

Andesaurus This titanosaur rivaled Argentinosaurus in size.

Antarctosaurus Despite its name, this titanosaur may or may not have lived in Antarctica.

Bonitasaura This titanosaur wasn't as beautiful as its name implies.

Epachthosaurus This "heavy lizard" was relatively primitive for its time and place.

Futalognkosaurus It sounds like a hot dog, but it was one of the biggest dinosaurs that ever lived.

Gondwanatitan Yet another titanosaur from South America.

Hypselosaurus This titanosaur's eggs were a foot in diameter.

Isisaurus Otherwise known as the Indian Statistical Institute Lizard.

Nemegtosaurus This titanosaur has been recreated from a single, incomplete skull.

Paralititan This huge sauropod was discovered recently in Egypt.

Quaesitosaurus This titanosaur may have had unusually sharp hearing.

Rapetosaurus The only sauropod ever to be discovered on modern-day Madagascar.

Saltasaurus The first armored sauropod ever to be discovered.

Titanosaurus This sauropod may--or may not--have been a unique member of its genus.

Argentinosaurus

Name:
Argentinosaurus (Greek for "Argentina lizard"); pronounced ARE-jen-teen-oh-SORE-us
Habitat:
Forests of South America
Historical Period:
Middle Cretaceous (100-90 million years ago)
Size and Weight:
Up to 130 feet long and 110 tons
Diet:
Plants
Distinguishing Characteristics:
Enormous size; long neck; relatively small head
About Argentinosaurus:

As you may have guessed from its name, the remains of Argentinosaurus were dug up in present-day Argentina, in South America. To date, researchers haven't found an entire skeleton, but what they have found--four-foot long vertebrae and five-foot-long tibiae--indicate that Argentinosaurus was a truly titanic sauropod (hence its classification in some circles as a titanosaur). See more facts, figures and news about Argentinosaurus and a gallery of Argentinosaurus pictures

Interestingly, the remains of Argentinosaurus were dug up near the fossils of another huge dinosaur--the carnivorous theropod Giganotosaurus. This has led paleontologists (and TV producers) to speculate that packs of Giganotosaurus may have hunted down full-grown Argentinosaurus adults--a chase that would have been deadly for any smaller creatures that happened to get in the way!