Fire Ecology of Australian Eucalypts
Eucalypts belong to the myrtle family (Myrtaceae), which are evergreen ‘tropical’ rainforest trees (Bowman 2000). Three genera are considered eucalypts: Eucalyptus, Angophora, and Corymbia. Roughly 600+ species of eucalypts exist today, and nearly all are endemic to Australia (farrer.riv.csu.edu.au). Although eucalypts began as members of the rainforest, the pressures of poor soil, increasing aridity and most importantly recurrent fires pushed them out of the rainforests and on to become the dominant species in a harsh land. Today, fire promoting traits such as volatile leaf oils, copious litter production, and highly flammable bark allow eucalypts to out-compete rainforest species for prime sites.
Geologic and Vegetative History of Australia
Before 250 mya, all continents were connected into a super-continent now called Pangaea. About 250 mya, Pangaea split into two continents—Laurasia (North America, Asia, and Europe) became the northern continent and Gondwana (South America, Africa, India, Antarctica, and Australia) the southern continent. At around 145 mya, the angiosperms arose in the center of Gondwana and spread outward. The continent of Gondwana began fragmenting around 120 mya, with the break-off of India; Australia began its northward trek about 45 mya.
At the time of its departure, a Gondwanic rainforest dominated by araucarias (early gymnosperms) and Nothofagus (southern beeches) covered Australia; the forests also contained members of the Myrtaceae family, from which the eucalypts arose about 34 mya. Soil cores from this period show very high counts in Nothofagus pollen, and very low levels of charcoal (Kershaw et al. 2002). While the presence of fire was felt in the ancient rainforest, its affects were relatively minor and infrequently felt. This forest covered most of Australia until the mid-Oligocene, roughly 28 mya.
The rainforest may have endured if the climate of Australia had not undergone dramatic climate changes during this time. As the continent moved towards the northeast at a rate of 6-7 cm yr-1, it grew increasingly more arid. A quiet geologic history resulted in a lack of tall mountain ranges, and the continent could not capture the moisture of incoming oceanic winds. Dry climate began to take its toll upon the Gondwana rainforest; soil cores from the mid-Oligocene to the mid-Miocene show a gradual decrease in Nothofagus pollen, and a gradual increase in Myrtaceae pollen counts. This is most likely explained as a move towards a warmer or more seasonal rainforest, due to the lack of grass species in Australia and low charcoal levels (Kershaw et al.
Millions of people all over the United States choose motorcycles over automobiles for the thrill, speed, and high performance capabilities. On the other hand, motorcycles are not at all the safest way of transportation. Motorcycles do not provide the passenger with the outer protection that cars provide, therefore, when one crashes, the results are usually much more serious. Injuries to the head are responsible for 76% of fatalities when dealing with motorcycle crashes many of which could have been prevented had the rider been wearing a helmet. For this reason, many states have adopted the motorcycle helmet law. The law states that every passengers must wear a helmet at all times when riding on a motorcycle. This law has created a great deal of controversy. One side supports the law, believing that it protects motorcyclists from danger and saves the economy a great deal of money. The other side argues that the law is unconstitutional and it violates our right to freedom. However, statistics show overwhelming support in favor of the motorcycle helmet law. Although wearing helmets cannot prevent motorcycle crashes, they can greatly reduce the number of deaths caused by head injury as well as lowering taxes, insurance rates, and health care costs. Therefore, the helmet law should be put into effect in every state across the United States.
About 200 million years ago there was one big continent called Pangaea. They believed that, this landmass began to separate. They believed that the Atlantic Ocean formed, dividing Africa and Eurasia from the Americas. Over the next several million years plants and animals changed and made to separate biological worlds. It wasn’t until Christopher Columbus and his crew sailed to the Americas in October 1492, they started interacting with each other.
ideas and perceptions of one will inevitably affect the other. These cultures had 600 years to interact with each other until the Normans came A.D. 1066, and the mix of the Celts’ Christianity and the Anglo-Saxon’s pagan belief system intermingled to create many interesting literary works. Perhaps most notable of these is Beowulf. With its blended Christian/pagan mythos and epic fight scenes, it has been a topic of discussion for centuries. Beowulf’s most impressive feat, however, is its ability to incorporate two very distinct ideologies without distorting either too heavily. From its gripping start to its morose ending, Beowulf maintains a consistent tone that balances Christianity with the Germanic heroic code.
The landmasses are divided into seven continents. They are Africa, Antarctica, Asia, Australia, North America, South America and Europe. But before there were seven it was said to be just one giant landmass called Pangaea. Supposedly this super continent began to break up about 225-200 million years ago, eventually coming into the position the continents are today.
Pangaea or Pangea is the name given to the supercontinent that existed during the Paleozoic and Mesozoic eras, before the process of plate tectonics separated each of the component continents into their current configuration. The movement of Earth’s tectonic plates formed Pangaea and ultimately broke it apart.
This breaking up of the mega continent of Pangaea allowed for more diversification of plant species and as the continents continued to break apart, plant life became even more diversified. As the continents shifted and moved from one area of the ocean to another the climates began to change drastically which allowed for plant and dinosaur species both to begin adapting to suit their new ecosystems. All the water that was produced by the split of Pangaea gave the previously hot and dry climate a more humid and drippy subtropical weather. Dry deserts took on a greener look. Before the Mesozoic Era, livings things were confined to only surviving in the oceans. It was not until the Jurassic Period that livings things evolved the capability of living on the land rather than just the ocean. Towards the beginning of the Jurassic, plant life evolved from Bryophytes, the low-growin...
Beowulf is considered one of the greatest epic hero poems of world literature. Although it is considered an ‘epic poem’ there are more characteristics of anglo-saxon hero criteria than epic hero criteria. To be an anglo-saxon hero there must be traces of loyalty/honesty, bravery/courage, generosity, and friendship. Beowulf meets all of the characteristics previously listed throughout the story, making him more of an anglo-saxon hero rather than an epic hero. E. Talbot Donaldson makes a remark on Beowulf saying “Courage is the instrument by which the hero realizes himself.” Beowulf is not necessarily a stereotypical hero, but his loyalty and courage make him stand out from the others in the reading.
Beowulf, written between the 8th and 10th centuries, is an epic poem set in southern Sweden. The poem illustrates the Anglo-Saxon’s strong belief in the heroic code. The loyalty between the warrior and his king bound the culture together. The warrior was the ultimate hero who represented strength and courage. Beowulf, the hero in the poem, illustrates the Germanic principles of the heroic code. Through the battles and character interactions, Beowulf converges loyalty, strength, courage and forgiveness into the hero archetype.
Retrieved on line July 7, 2005, from http://www.fs.fed.us/rm/pubs/rmrs_gtr42_2.html Audesirk, T. (2003). Life on the Earth. In (Ed.) :. ), (3rd ed. , pp. 581-620.
Thesis: Politicians are proposing sweeping changes in bills, which have caused great controversy, in efforts to correct the problems that the Forest Service has
Anglo Saxon’s history is well known for their loyalty, courage and bravery. Beowulf our protagonist is symbolized as a hero, who represents the Anglo Saxons at the time. Beowulf earns his fame and respect through battling creatures nobody else would want to face. These creatures symbolize the evil that lurks beyond the dark. Beowulf’s intense battle with these creatures’ symbolizes the epic battle of good versus evil. In the end good triumphs over evil but one cannot avoid death. Beowulf’s death can be symbolized as the death of the Anglo Saxons. Beowulf’s battle through the poem reflects the kind of culture that the Anglo Saxons had. The youth of a warrior to his maturity then the last fight which results in death. Beowulf wanted to be remembered and be told in stories that are passed on from generation to generation after his death. These story tellers relate to the Anglo Saxons time when they told stories about their great heroes.
Beowulf is an epic poem that, above all, gives the reader an idea of a time long past; a time when the most important values were courage and integrity. The only factors that could bestow shower fame upon a person were heroic deeds and family lineage. Beowulf, as the paradigm of pagan heroes, exhibited his desire to amass fame and fortune; the only way to do so was to avenge the death of others. This theme of retribution that is ever present throughout the poem seems to color the identities of its characters.
Thesis: Forests provide the earth with a regulated climate, strong biodiversity, and good nutrient rich soil for plants to strive on.
Tharaud, Barry. “Anglo-Saxon Language and Traditions in Beowulf.” In Readings on Beowulf, edited by Stephen P. Thompson. San Diego: Greenhaven Press,1998.
Today, when people want to cross over the ocean and get to another continent, they have to take plane for eight or more hours or ship for few days. However, if people were born millions of years ago, they might easily cross a boundary of tow continents by accident. Because according to the continental drift theory, ages ago, the continents today were a completed one piece and called Pangaea. (Sandner, 506-507)