Sunday, October 14, 2012

How Much Time Should I Invest In Studying Organic Chemistry?

As an organic chemistry tutor, one of the questions often asked by my students is as follows:

How much time should I invest in my Organic Chemistry studies?

And while the answer will be different for every single student, I do have a 'ballpark' figure. If you are taking organic chemistry for the first time, in the Spring or Fall semester, you should expect and aim to invest a minimum of 10 study hours per week.

NO LESS

Organic chemistry is not easy, and I have a series of recommended steps to help you understand and properly master the information. But if you approach this course as you did any other course, perhaps with the intention of studying just 2 hours a week think again. If you are the type of student who only studies the night before an exam.

THINK AGAIN

Organic chemistry is a difficult course containing many vital concepts and foundation topics that have to be studied and mastered slowly over time. The concepts are all connected, which means you will be constantly building upon the foundation of the material you have studied beforehand.

But TEN hours a week, is there even enough material for so much study?

Of course there is the first and most important study step; reading the book prior to attending lecture. If you attempt to understand the information by hearing it for the first time in lecture you will be lost within five minutes.

Instead, I recommend that you expose yourself to the material prior to attending the lecture. You may not understand much of what you are reading, but at least you will have this initial exposure.

Once your professor begins explaining concepts, hopefully the information will start falling into place.

Now that you have attended the lecture, you are likely still confused about some of the topics, and so it is time to read the textbook AGAIN.

This time however, don't just skim the information. Instead you should take the time to read through each paragraph carefully. Ensure that you understand every topic mentioned, and that you are able to follow every practice example given.

Most textbooks will include a practice problem or two after each concept taught. Test yourself by doing this problem. If you get it correct, AND understand every aspect of the question, then you can move on. If you are not fully confident with the material so far, go back and review again.

This initial chapter study process should take you a few hours minimum.

The next step is to do the practice problems at the end of the chapter to ensure that you are able to apply what you have studied to different formats of the question.

Rinse and Repeat (meaning do this all over again. Read, practice, end of chapter problems)

Sometimes your textbook is not enough, that's where external resources come in handy. Some of these include Organic Chemistry Tutorial Videos practice quizzes and more.

Or go the full mile and hire an organic chemistry tutor to help you break down and understand the concepts in depth as you are learning them in class.

Sunday, October 7, 2012

Ark Of The Covenant Mystery Solved By Investigative Dowsing

The ability to dowse is a God given gift. It is generally accepted that we were endowed with the dowsing ability to insure man's survival. Simply giving us the ability to find water was enough to justify affording man this important tool.

Because dowsing has unlimited uses, and there are two basic forms of dowsing, it is well suited to answer questions like what happened to the Ark of the Covenant, the Holy Stone Tablets it contained, and resolve other Biblical and Archeological mysteries.

One form of dowsing allows us to ask any question that can be answered with a yes, no, or a true or false answer. Because so much has been written by scholars about such subjects as the Ark of the Covenant, a skilled dowser only needs to pose questions around each theory or supposition that has been put forth to determine if any factual truths emerge. Once a truth is uncovered within the theories and suppositions of scholars, the questions can be bracketed down to hone in on important smaller details. With enough clues, and by formulating the proper questions, a dowser can paint an accurate picture of what transpired in any time frame.

Another form of dowsing is known as map dowsing. Map dowsing can be used to find any material object as long as enough information is available to initiate a search for the location of the object on a map. It is often used to locate water, oil and gas deposits, missing persons, lost buried or hidden treasures, prehistoric river beds and shore lines, earthquake faults, sunken treasure ships, and lost items, just to name a few.

Where is the Ark of The Covenant?

Dowsing Research Results:

The original Ark of the Covenant no longer exists. During the Babylonian invasion in 586 BC, while Jerusalem was plundered, the Ark was found by the invading soldiers, stripped of its gold, and discarded along with the Holy Stone Tablets it contained.

After five years passed, the Babylonian hierarchy, apparently concerned about the destruction of the original Ark, commissioned a replica of the Ark to be made. It is this replica of the Ark of the Covenant that eventually found its way to the Church of Saint Mary of Zion in Axum, Ethiopia.

What Happened to The Holy Stone Tablets in The Ark of the Covenant?

Dowsing Research Results:

Four days after the desecration of the Ark took place, the tablets were recovered from the ruins of the temple, and were taken on a journey across the desert. Unfortunately, they never reached their destination. They are buried under eighteen feet of windblown sand one hundred and twenty miles South East of Jerusalem. Indications are that the individual transporting the tablets, and his camel, perished from lack of water, or befell some other misfortune. In any case, the tablets could possibly be found and recovered using a modern, sophisticated ground-penetrating radar system. In order to determine who actually recovered and saved the tablets from destruction, a dowser would only need to have a list of potential names to dowse from.

In Conclusion:

I don't know what caused me to deviate from my normal dowsing activities to invest time in this project, as I have never had any curiosity or interest in subjects of this nature. I can only attribute my involvement to unsolicited Divine Inspiration.

"ABOUT THE AUTHOR": Jerry Nokes with over thirty-five years of dowsing experience, through constant practice and a dedication to perfection, is responsible for discovering previously unknown innovations relating to the science of map dowsing.

Tuesday, October 2, 2012

The Life Cycle of the Red Fire Ant

Anyone who has spent significant time in the southern United States has come into contact or been warned about the fire ant. These little creatures bite and leave an itchy and uncomfortable mark where the bite occurred. These ants are widespread and native to the United States. They occupy much of the southern United States from Florida, up to the Carolinas, and then all the way west to California.

The life cycle of the fire ant is similar to most other ants. The life cycle of these insects follows the pattern of egg, larva, pupae, and finally the adult ant. While individual ant life cycle is an interesting point, there is a broader issue of the life cycle of the colony. Ants operate as a collective and therefore the life cycle of their colony is an interesting study.

There are multiple types of ants within a colony that all serve different functions. The most notable of the types of ants in a colony is the queen. The queen is the largest ant in the colony and their primary function is breeding. The queen can produce up to 3,500 eggs in a day and survive around 6 or 7 years. This means that a single queen fire ant can produce over 8 million eggs in here lifetime.

Queen ants are able to produce so many offspring that they may fill a nest. Queens have been observed leaving the nest with a set of workers in order to form new colonies. The queen's natural instinct is to expand and this helps to facilitate that instinct. These new colonies are usually very close to the first one and can lead to quite the issue if these colonies are around a person's yard.

Males or drones serve only one purpose in an ant colony, which is mating with the queen. The drone ants have a short lifespan, typically around 4 or 5 days. The drone ants have wings, similar to queen ants, but the difference is that these wings are permanent.

The third type of ant in a colony is the worker ant. These ants are sterile females and have a myriad of functions within the colony. The workers serve as the defense against predators and build the nests. Most of the ants people meet are worker ants that are out in search of food or supplies used for maintaining the nests. The workers are able to build very intricate nests that have many different areas for adult ants and nursery-type areas for ants that are not adults yet. The average lifespan of the worker ants is around five weeks.

While fire ants are a serious pest issue in the south, they can easily be dealt with. Due to their prevalence, many pest control companies are experts at seeking out the issues with fire ants and dealing with them accordingly. Additionally, fire ants are not deadly unless the human has an allergy present, although the stings are very uncomfortable. If you feel as though you have a serious issue with fire ants, contact your local pest control company immediately.

Monday, October 1, 2012

Halogenation of Alkenes

While studying alkene reaction mechanisms in organic chemistry, you are very likely to come across the halogenation mechanism.

This mechanism is different from the standard alkene addition reactions given the unique nature of the halogen bridge formed as an intermediate of this reactions

Which Molecules Are Involved in Halogenation of Alkenes
Halogenation of alkenes involves the addition of a dihalide onto a carbon to carbon double bound. Dihalides are molecules composed of two atoms of the same halogen bound to each other including fluorine, chlorine, bromine, and iodine.

How Do These Molecules Reaction
The carbons involved in the doubled bound alkene are sp2 hybridized, meaning trigonal planar or flat. The double bond resides in the overlapping 'p' orbital which sits well above and well below the flat molecule. Having the electrons stick out so much from the molcule allows them to attack a nearby molecule as desired

A dihalogen is composed of two equal electronegative atoms. While the bond between them is a non-polar bond, meaning there is equal sharing of electrons, there does exist the phenomenon of induced polarity which makes the molecule temporarily polar

The concept of induced polarity occurs when a negative group such as the pi electrons get too close the halogen molecule. The pi electrons temporarily repel the electrons of the closer halogen onto it's bound partner, making it temporarily partial positive, and the other atom partial negative.

This brief change in polarity induces enough of a partial charge to cause the pi electrons on the alkene to break out of their double bond and attack the halogen.
The bond between the two halides collpase as a result and break onto the second halogen leaving it as a negative ion in solution

The Halogen Bridge
After the pi bond breaks, one of the original attacking carbons will be bound to the halogen, and the second one will have a positive charge due to the loss of the pi bond.
The halogen, while neutral and happy to be bound to the carbon, is still an electronegative atom and will reach out with one lone pair of electrons to attack the positive neighboring carbocation

This second attack by the halogen leaves the atom bound to both carbons. Of the 8 original halide electrons, 4 are now involved in bonding, 4 are found as 2 lone pairs, and the resulting atom has a positive charge. This phenomenon is called a halogen bridge and is not very stable. Some of the negativity is passed onto the connected carbon atoms making them both partially positive

Attacking the Carbon-Halogen Bridge
The free negative halide in solution, which came from the original dihalide molecule is attracted to the partially positive carbon atoms. The halogen bridge sitting on one side of the molecule completely crowds that area and thus prevents the second halide from attacking from the same side.

Instead, the negative halide is forced to attack the partially positive carbons from the opposite side as the halogen bridge. This attack on the carbon atom breaks the halogen bridge by kicking the electrons off the attacked carbon and onto the first halogen atom.

Charge of the Final Product
Having a negative halogen attacking a positive carbon-halogen group cancels out all the charges yielding a neutral final product. This type of reaction is considered an 'anti' reaction given that the second group attacked from the opposite side as the first group.

Structure of the Final Product
The final product is an alkane with two halogen atoms bound to neighboring carbons. These former sp2 carbons are now sp3 hybridized, each is bound to four groups, and has a tetrahedral conformation

Monday, September 24, 2012

Flight Dynamics of Giant Pterosaurs Explained

Researchers Propose that Quetzalcoatlus Used Cretaceous Runways to Take Off and Land

Scientists from the Museum of Texas Tech University have used computer modelling to assess how the last of the Pterosaurs (flying reptiles) took to the air. Pterosaurs, evolved during the Triassic and they went onto dominate the skies for much of the Mesozoic, until the emergence of the Aves (birds). The very last types of flying reptile were giants, creatures like Hatzegopteryx thambema from Europe and Quetzalcoatlus northropi whose fossils have been found in the Big Bend National Park of Texas. These Pterosaurs were members of the Azhdarchidae and some of these animals were the largest flying creatures known to science with wingspans in excess of ten metres reported. Quetzalcoatlus, for example, had a wingspan greater than that of an American F-16 jet fighter. Seeing this huge animal, many times bigger than the largest birds today, soaring overhead would have been a truly memorable sight. However, how such large and heavy creatures took to the air has puzzled palaeontologists ever since the first fossils of these giant Pterosaurs were discovered.

Creating a Model of Flying Reptile Flight

One University of Texas academic, Sankar Chatterjee (Horn Professor of Geosciences and Curator of the Palaeontology Department at the University's Museum), has suggested that these enormous creatures needed down-sloping runways to enable them to take off. The scientist presented a paper detailing his work on the aerodynamics of Azhdarchidae Pterosaurs at the recent annual meeting of the Geological Society of America in Charlotte (North Carolina).

After a careful, three-dimensional study of Azhdarchid fossils, Professor Chatterjee and his colleagues developed a computer simulation that showed how such an ungainly looking animal would have used a run up in order to gain momentum before finally being able to achieve lift off. Landing would also have been very tricky for these animals, which some palaeontologists estimate may have weighed more than two hundred kilogrammes. When coming into land, the large wings would have acted like giant air brakes, and the Pterosaur would effectively "stall" before touchdown with its hind legs contacting the ground first and then the front of the body and the large head would pitch forward and a quadrupedal stance would be adopted as the flying reptile came to a halt.

Commenting on his research, Professor Chatterjee stated that Azhdarchid Pterosaurs had a similar lifestyle to the modern-day frigate bird or albatross. They could spend a long time in the air with the minimum of effort. However, when it comes to landing and taking off, Pterosaurs would have been very awkward and ungainly. Launching from a cliff top would have been ideal, but where fossils of the Quetzalcoatlus have been found in Texas, these represent non-marine sediments, there were no sea cliffs for these creatures to use. To become airborne a Quetzalcoatlus would have to find a sloping area such as a river bank, a downward slope of just ten degrees would have been adequate. By running, first on all fours and then on two legs, speed could be built up and enough momentum generated to take off. These Pterosaurs needed plenty of room, they needed an area to taxi.

Did Flying Reptiles "Vault" into the Air?

In 2010, a study published in the open access and on line journal "Public Library of Science" proposed that the largest of the Pterosaurs launched themselves into the air by using their strong leg and arm muscles to "vault" upwards. This work was conducted by researchers based at the University of Portsmouth (England). Professor Chatterjee and his colleagues do not agree with these earlier findings. They postulate that such a method of taking to the air may be proven in small bats, but when it comes to a two hundred kilogramme Pterosaur with a wingspan in excess of ten metres; this method of becoming airborne is simply not viable.

Relying on Thermals to Stay Aloft

The Texas based team report that once animals got to a certain size they would not have had the strength and power required to vault into the air. They contend that the only way these large flying reptiles could get airborne would be by taking a long run up, preferably into the wind along a downward sloping bank or similar stretch of ground. Starting on all fours, the animal would quickly switch to a bipedal stance and build up running speed, then just like a modern-day hang glider, it would launch itself into the air, pick up a thermal and rapidly gain height.

Reaching Air Speeds of Over Thirty-Five Miles per Hour

The computer model suggests that these animals could not beat their wings very rapidly. With a high-aspect-ratio wing, similar to that observed today with modern petrels and albatrosses, the Azhdarchid Pterosaurs would rely on thermals and air currents to keep them aloft with the minimum of effort. The animals would have been vulnerable and ungainly on the ground but once in the air they could soar for hours. Professor Chatterjee and his team have suggested that such creatures could attain air speeds in excess of 36 mph (58 kmh).

These enormous creatures, some of which stood taller than a giraffe, were aerial masters, the very last of their kind. Pterosaurs died out at the end of the Cretaceous some sixty-five million years ago. All we have now are their amazing fossils that can be studied so that we can understand how these creatures were able to fly.

Everything Dinosaur is a company run by parents, teachers and real dinosaur experts. It specialises in developing educational dinosaur toys, models, clothing and games and strives to help young people learn more about science through their fascination with prehistoric animals. Many of the items featured on the Everything Dinosaur website Everything Dinosaur have been designed and tested by the teachers and real dinosaur experts in the company.

Our aim is to help young people learn more about Earth sciences through their fascination with dinosaurs and other prehistoric animals. Team members are happy to provide advice and support supplying free quizzes, drawing materials, puzzles, games even recipes for dinosaur themed biscuits and birthday cakes. With something like 900 products on line including dinosaur party supplies, Everything Dinosaur has built up a strong reputation assisting parents, guardians and fellow teachers, helping young people to learn more about science through creative play.

Monday, September 17, 2012

Predator/Prey Relationships in Miocene Spain

Joint American and Spanish Team Study Teeth to find out what Sabre-Toothed Cats Ate

A ratio of Carbon 12 to Carbon 13 isotopes preserved in the fossilised teeth of apex predators and herbivores that lived over nine million years ago has provided a joint American and Spanish research team with an insight into how food chains worked in the latter part of the Miocene epoch. The study, the academic paper having been published in the scientific journal "The Proceedings of the Royal Society of Biology", focused on the diets of the top, predatory mammals and attempted to establish how large carnivores such as Sabre-Toothed Cats and Bear Dogs (Amphicyonids) were able to live in the same habitats without necessarily competing for the same food resources.

Miocene Fossil Locations of Central Spain

Palaeontologists from the Museo Nacional de Ciencias Naturales (Madrid) and the University of Michigan (United States) studied the fossilised teeth of specimens of animals that had been found at a number of fossil dig sites at Cerro de los Batallones, just 25 miles south-west of Madrid. A substantial number of vertebrate skeletons have been discovered in this area, two dig sites are particularly rich in predator fossil bones. Scientists suspect these sites represent "natural predator traps", a herbivore may have become stuck fast in mud and this then attracted a number of carnivores and scavengers to the location hoping to feed on the hapless plant-eater. The meat-eaters soon became stuck too, and the rising pile of corpses would have attracted more and more predators, thus the number of carnivore fossil specimens found at such sites are far in excess of the number of herbivore fossil specimens found. Fossils found include those of hyenas, martens and skunks.

Two Types Sabre-Toothed Cat Studied

The researchers studied two species of Sabre-Tooth Cat, Promegantereon ogygia, about the size of an African Leopard (Panthero pardus pardus) and the much larger and heavier Machairodus aphanistus, which was about the size of an extant African Lion (Panthero leo). It is quite common to hear people describe Sabre-Toothed Cats as "Sabre-Toothed Tigers", this is an inaccurate description, as although Sabre-Tooths do belong to the same taxonomic family as today's "Big Cats" - Felidae, Sabre-Tooth Cats are not closely related to Tigers.

The Fearsome Bear Dogs

The other type of apex predator the research team studied was the Bear Dog known as Magericyon anceps. Bear Dogs are neither Bears or Dogs but seem to be distantly related to both types of carnivore, sharing a common Vulpavine ancestor. M. anceps was a particularly large and powerful example of the Mid to Late Miocene Bear Dogs, large specimens could weigh over 200 kilogrammes and would have stood over a metre high at the shoulder.

Apex Predators Co-existing

The study of the tooth isotopes revealed that the Sabre-Toothed Cats shared the same woodland habitat. The smaller Sabre-Tooth Cat species probably used the abundant cover to avoid encounters with M. aphanistus. Sabre-Toothed Cats have a different build when compared to modern cats. They are not built for speed but have immensely strong front legs and shoulders. Scientists have speculated that Sabre-Toothed Cats specialised in being ambush predators rather than pursuit predators, chasing after their prey. The woodland habitat would have been ideal for ambushing herbivores.

Sabre-Toothed Cats - Likely Ambush Hunters

Both species of Sabre-Toothed Cat showed no statistical differences in the ratio of Carbon 12 to Carbon 13 in their teeth samples. This means that they probably fed on similar prey animals that lived in the woodlands, but their body sizes probably meant that they targeted different sized prey. They may also have avoided direct competition by hunting at different times of the day. It has been speculated that Promegantereon ogygia may have hunted after dusk, or spent more time in the trees, so as to avoid the attentions of larger types of Sabre-Tooth Cat in the area. It seems that the members of the Machairodontinae living in the area that was to become central Spain preferred to eat primitive horses, animals that were not yet the highly efficient runners seen on race tracks today.

Bear Dogs "Top Dog" on the Open Plains

The tests on the Bear Dog teeth showed a different ratio, indicating that a different type of prey was preferred by these carnivores. The Bear Dogs hunted animals that lived in more open, grassland habitats, they seem to have been better suited to pursuit predation, tackling herbivores that lived in open areas such as antelopes.

It seems that nine million years ago, a number of mammalian apex predators were able to co-exist in this part of Europe as they seem to have specialised in hunting different types of prey animal.

Providing an Insight into an Ancient Miocene Ecosystem

Commenting on the study one of the researchers stated that such investigations using isotope analysis of fossil teeth provided an insight into the diets of long extinct creatures. This in turn gave the palaeontologists an understanding of an ancient, long extinct ecosystem.

Everything Dinosaur is a company run by parents, teachers and real dinosaur experts. It specialises in developing educational dinosaur toys, models, clothing and games and strives to help young people learn more about science through their fascination with prehistoric animals. Many of the items featured on the Everything Dinosaur website Everything Dinosaur have been designed and tested by the teachers and real dinosaur experts in the company.

To learn more about the products and services we offer at Everything Dinosaur click on our website links.

Our aim is to help young people learn more about Earth sciences through their fascination with dinosaurs and other prehistoric animals. Team members are happy to provide advice and support supplying free quizzes, drawing materials, puzzles, games even recipes for dinosaur themed biscuits and birthday cakes. With something like 900 products on line including dinosaur party supplies, Everything Dinosaur has built up a strong reputation assisting parents, guardians and fellow teachers, helping young people to learn more about science through creative play.

Monday, September 10, 2012

New Super Predator from Africa - Sauroniops pachytholus

Sauroniops pachytholus - Palaeontologists turn to Tolkien to Name a New Dinosaur

A new super-sized meat-eating dinosaur has been named by a team of scientists after the evil Eye of Sauron from the Lord of the Rings books written by J. R. R. Tolkien. The inspiration for naming a new genus of organism can come from many things, but since this new predatory dinosaur is only known from a fragment of skull bone that was positioned directly above the eye socket (orbit) the name Sauroniops pachytholus seems entirely appropriate. The name means "thick domed eye of Sauron", in reference to the bump and thickened portion of the skull fragment studied.

The Kem Kem Formation of Morocco and Algeria represents a series of strata laid down in the Cretaceous (Albian to Cenomanian faunal stages), approximately 95 to 100 million years ago. The majority of the deposits represent an inter-tidal, estuarine environment, with wide lagoons, and broad, flat flood plains crossed by many rivers further inland. The environment supported and extensive and diverse flora and fauna, so rich in fact that this area probably supported the largest number of apex predators in any known Mesozoic habitat. A number of meat-eating dinosaurs have been associated with the Kem Kem Formation, most named from fragmentary fossil material just like Sauroniops. The list of predators reads like a "who's who" of Theropod dinosaurs - Carcharodontosaurus, Deltadromeus, Spinosaurus, Rugops and now the 13 metre long Sauroniops joins their ranks.

A Range of Theropods in the Fossil Record of Morocco

Palaeontologists had long suspected that there were other Theropod dinosaurs awaiting discovery from the sedimentary rocks of this region. The strata from south-west Morocco for example, had yielded a large number of fossilised Theropod teeth, these had yet to be assigned to any particular genus. One of the problems with the strata in this part of the world is that the fossils found within them are extremely fragmentary in nature. The action of river water and the tides has jumbled up and dis-articulated any fossil bones and teeth that have survived, the fossiliferous deposits have been described by palaeontologists as if all the fossils had been put into a blender, the blender turned on and the resulting mix re-deposited.

Identifying the New Dinosauria Genus

The age of the fossil bearing rocks of south-eastern Morocco is disputed, in the case of this new dinosaur genus, the exact age of the fossils appertaining to Sauroniops is further complicated as it is difficult to pinpoint exactly where this fossil material was found. A private collector purchased the fossil bone from a local fossil trader in Morocco, the trader stated that the fossil was purchased himself from local fossil hunters near to the small village of Taouz, which itself is located in a mountainous region close to the border with Algeria. The private collector later donated this specimen to a Museum located at Montevarchi in central Italy (Tuscany).

Small Piece of Skull Bone to Study

With just an isolated fragment of skull material measuring 18.5 centimetres in length to work with, a team of Italian scientists compared the shape and structure of this part of the skull (left frontal bone) with those of other meat-eating dinosaurs known from the Kem Kem Formation and concluded that this fragment (assigned the identification code of MPM 2594) was indeed attributable to a new type of carnivorous dinosaur. An academic paper has just been published in the scientific journal Acta Palaeontologica Polonica, some five years after the fossil was acquired by the private collector.

The "Eye of Sauron"

Based on comparisons with the skulls of other Theropods, the palaeontologists have estimated that Sauroniops may have been up to thirteen metres in length, establishing "the eye of Sauron" as one of the apex predators known from this part of the world. One of the lead authors of the scientific paper, Andrea Cau commented that with the frontal bone to study, the only part of this dinosaur known, it seemed appropriate to name the fearsome creature after the evil eye of Sauron from the J. R. R. Tolkien novels.

Given the paucity of the fossil material, it is extremely difficult to assign any further characteristics to this new dinosaur species, however, S. pachytholus has been tentatively assigned to the Carcharodontosauridae and placed close to Eocarcharia, which itself has been described from a maxilla and a parietal bone (skull bones found in the Sahara).

Evidence of Intra-specific Contests Amongst Theropods

The bump and raised portion of the skull has been seen in other Carcharodontids as well as Abelisaurids. The scientists have speculated that these animals had crests over their eyes which indicated that they were mature, breeding adults. These bumps and crests may have been brightly coloured and acted as signalling devices in non-verbal communication between members of the same species. It has even been suggested that these thickened portions of the skull evolved as a result of intra-specific competition. Animals of the same species competing with each other to win mates, social status, fight over the carcases of other dinosaurs and so on. Perhaps the Carcharodontids and their relatives were "head bumpers".

A Number of Predatory Dinosaurs in the Area

The palaeontologists have concluded that the environment in this part of north Africa during the Cretaceous must have been particularly favourable to herbivorous dinosaurs and other creatures that would have made up the food chain. It would have needed to be to support the number of large, predatory dinosaurs now known from this part of the world.