Kingdom: Animalia

                                                           Phylum: Chordata

                                                              Class: Mammalia

                                                                  Order: Diprotodontia

                                                                       Family: Macropodidae

                                                                           Genus: Macropus

                                                                                Species: rufus

Many of us have seen a kangaroo on television or possibly at the zoo, but most of us have not experienced them running in the wild. Perhaps that is because Macropus rufus, commonly known as the red kangaroo, ranges throughout the grass and scrublands of central Australia. Male M. rufus have red-brown fur fading to bluff below and on limbs, while the smaller females tend to have blue-grey fur with a brown tinge. Being the largest among the Macropus species, M. rufus contain long, pointed ears with a squared off muzzle. They also contain two muscular hind limbs, allowing them to jump a near 30 feet! Their long tail provides this species stability when standing upright, essentially creating a tripod effect.

M. rufus gain their capability to reproduce around the age of 18 months. This particular species is a marsupial animal that reproduces sexually. Once a female’s egg has been fertilized it takes about 33 days for the neonate to emerge into the mother’s pouch; this emergence takes only about 3 minutes. The M. rufus neonate is hairless, blind, and only mere centimeters long. Although its hind-legs are not quite yet developed, its forearms do the climbing through the mother’s thick abdominal fur. Once in the pouch the neonate begins feeding, at this time the mother’s reproduction cycle begins again. However this time when the egg is fertilized, the development is halted. After 235 days of the joey prodigiously growing, it will make its last trip out of the mother’s pouch. At this time the newly fertilized neonate will crawl into its mother’s pouch and begin feeding, starting the reproduction cycle all over again.<iframe title="YouTube video player" width="853" height="510" src="http://www.youtube.com/embed/fPIpJMnuvpA" frameborder="0" allowfullscreen></iframe><iframe title="YouTube video player" width="853" height="510" src="http://www.youtube.com/embed/4DZnx1mGyq4" frameborder="0" allowfullscreen></iframe>

Cronin, L. 2008. Cronin’s Key Guide Australian Mammals. Sydney: Allen & Unwin.

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Red Kangaroo (Macropus Rufus)

Kangaroo survival in Australia - BBC wildlife

Have you ever gone out and picked fresh mushrooms to use for dinner? Many of us do not, however, in Europe many families take day trips to the fields to pick their fresh mushrooms. Although it is an every day occurrence in Europe, not just anyone can go out and pick mushrooms; it is extremely important that one is thoroughly educated on the many mushroom types. Clitocybe dealbata is one type of mushroom that can be easily found in the fields, however, C. dealbata is not the mushroom one is hoping to stumble across.

C. dealbata is a small, funnel shaped toadstool. Its buff-coloured appearance is also croweded with white adnate gills. C. dealbata’s stipe has a pink-ochre flesh. C. dealbata can easily be mistaken for Marasmius oreades. Although taxonomically appearing to be a typical edible mushroom, C. dealbata is not.

C. dealbata contains a deadly toxic, known as muscarine. Muscarine, when ingested, closely resembles the function of the natural neurotransmitter acetylcholine in part of the human nervous system. If muscarine is ingested it will immediately attack the Central Nervous System. This in return causes involuntary actions to occur such as excess salivation, lactation, vomiting, diarrhea, tears and perspiration. Many also experience a rise in blood pressure and difficulty breathing. Ingesting C. dealbata is obviously not a pleasant experience, therefore, it is extremely important to know the many different types of mushrooms before eating.

http://www.youtube.com/watch?v=I_rRgWewVN8

http://www.youtube.com/watch?v=6m4QQ_n6bq0&feature=related

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Literature Cited

Beug, M. Poisonous and Hallucinogenic Mushrooms. Unpublished manuscript, The Evergreen State College, Olympia, Washington. Retrieved From http://academic.evergreen.edu/projects/mushrooms/phm/s37.htm

Bacteria cause most dental problems

      Are your teeth being attacked by terrorists? Whether you realize it or not, your teeth, in fact, are. Streptococcus mutans in many ways is a terrorist to our teeth. S. mutans can, most commonly, be recognized as plaque on the surface of teeth. This particular bacterium metabolizes sucrose producing polysaccharides, so the bacteria can cohere to one another. Once S. mutans secures itself to the tooth's surface, acids are secreted. This acid causes the breakdown of tooth enamel, which is ultimately the host of S. mutans. Breaking down tooth enamel causes dental carries, which is a prevalent disease among mankind.

       Most all of us at some point in our lives have experienced dental caries. One may wonder why dental caries are so common? Simply, S. mutans feeds off of sucrose, which is found in our life-sustaining substance, food. In order to prevent dental caries, it is necessary to brush our teeth after each meal. Although this statement may seem cliché, it is the single most effective way to rid the mouth of as much sucrose as possible. So, brush, brush, brush, so S. mutans is no longer a terrorist in your mouth! 

How often do you hear someone say Salmonella typhi has given me Typhoid fever? Truly, we do not; Typhoid fever is a rare occurrence in our society. However, in many third world countries, S. typhi effects nearly 17 million people a year, posing major life-threatening concerns. S. typhi is transported from infected individuals to healthy ones via fecal-oral route. When infected individuals defecate, they shed S. typhi. S. typhi produces and secretes a protein, invasin. Invasin causes the non-phagocytic cells to take up the bacterium. Invasin also causes the inactivation of the oxidative burst of leukocytes, preventing our innate immune responses.

Many un-established countries do not properly dispose of human feces, nor do they have sanitary water sources. Since, some countries do not properly dispose of human feces, the S. typhi infested feces comes in contact with their water system, which the healthy individuals drink. Once the healthy individuals drink the S. typhi tainted water, they become infected, resulting immediately in Typhoid fever. Typhoid fever suddenly onsets fever. Along with fever, infected individuals experience severe nausea, headaches and loss of appetite. This bacteria will also cause the spleen to become enlarged, meningitis to develop, and may cause malaise.

The key to avoiding being infected by S. typhi is to avoid fecal contaminated water. In order to control transmission, proper hygiene, waste management, and water purification must be maintained. The United States and like countries have immunizations to prevent the harmful effects of S. typhi, however, these third world countries that lack water purification, proper fecal disposal and hygiene, also lack immunizations. Typhoid fever, when left untreated, does in most all cases result in death. 


Literature Cited
Intestinal bug. (2008). Unpublished manuscript, Medical Center, University of Maryland, Maryland. Retrieved from http://www.umm.edu/news/releases/bug.htm

Many of us can recall a time seeing a ladybug on the ground, picking it up, just to watch it fly away. Although we can all relate to such an experience, we may have not all realized the significance ladybugs have on the environment. There are many species in the ladybug family, Coccinellidae. One specific ladybug is the Coccinella septempunctata Linnaeus, also known as the seven spotted lady beetle. These Coccinella septempunctata have oval shaped bodies, containing wings. Being brightly colored, C. septempunctata also have chewing mandibles to inhibit their predator behavior. C. septempunctata prey and feed primarily on aphids. C. septempunctata contribute to the environment by ridding it of overpopulated pests. Although C. septempunctata help to rid the environment of pests, it has pests of its own. The most common parasitoid of C. septempuntata is the Perilitus coccinellae, braconid wasp. C. septempunctata, also, have many defense mechanisms, interesting brooding behavior and habitats.

Defense Mechanisms

Accounting for their lack of size, C. septempunctata are brightly colored. These bright colors repel predators in fear that they are poisonous. C. septempunctata also have innate defense mechanisms. A C. septempunctata is capable of secreting a noxious fluid from its tibio-femoral articulations, or leg joints. This noxious fluid, hemolymph, is the C. septempunctata’s most efficient way to repel predators. This yellow hemolymph has such a repulsive smell that it causes predators not to approach the species.

Brooding Mechanism

Larger than males, adult female C. septempunctata lay their eggs in clusters. Eggs are most commonly laid on plants in the vicinity of aphids. The eggs then progress to the larvae stage. C. septempunctata larvae have a spotted, spiked, yellow and blue alligator appearance. Even at the larvae stage C. septempunctata are predators.  Although the larvae have an intimidating appearance, they are harmless.  After feeding on insects for several weeks, the larvae will pupate on a leaf. The new adult C. septempunctata will remain in the birthing location until pests become scarce.  Through the course of a year, C. septempunctata will go through several generations. Winter months slow the reproduction process, due to adult hibernation. 

Ecology

The C. septempunctata is native to Europe, and was introduced to Florida to help manage the population of aphids. This species typically resides in areas that are high in aphids because that is, after all, the main food supply of C. septempunctata.

Biological Control

Although minute in appearance, C. septempunctata are, interestingly, very useful in biological control. C. septempunctata are beneficial because they are predators of pests. Many gardeners spray pesticide on the eggs and larvae of the C. septempunctata thinking that it is a pest, however, ridding the garden of C. septempunctata only causes more pests to arise. While C. septempunctata control the population of many pests, they are also controlling the spread of disease.

Manipulative, augmentative, and inoculative biological control is being used on C. septempunctata to preserve and establish populations of C. septempunctata. Making conditions as favorable as possible for C. septempunctata, manipulative biological control is used. Augmentative biological control is also used to preserve C. septempunctata by purchasing C. septempunctata from commercial producers. C. septempunctata are purchased to augment the already present C. septempunctata. Lastly, placing C. septempunctata in areas that do not already contain C. semptempunctata is used to establish a population. This process is referred to as inoculative biological control.  

Bessin, R. (2007). Ladybugs. Unpublished manuscript, Department of Entomology, University of Kentucky, Kentucky. Retrieved from http://www.ca.uky.edu/entomology/entfacts/ef105.asp

Frank, J. (n.d.). Ladybugs of florida, coleoptera: coccinellidae1. Unpublished manuscript, Department of Agriculture, University of Florida, Gainseville, Florida. Retrieved from http://edis.ifas.ufl.edu/in327