Chapter 6 of Diseases and Human Evolution discussed schistosomes, or parasitic worms. I didn’t know snails were a vector of these types of parasites. The most important evolutionary mechanism that stood out to me was that Schistosomiasis haematobium mostly infects children. Because high levels of the eggs become displaced, the parasite continues to cause havoc in the body, causing the bladder to be unable to contract and expand, and can ultimately cause bladder cancer. This is the evolutionary mechanism. Even though you are expected to have resistance to reinfection, even though you don’t experience any symptoms, the eggs and flukes continue to live in your body with the potential to cause problems years down the line. Dormancy as a whole is something many parasites share, and it is a mechanism that allows them to continue to reproduce and thrive. …show more content…
While it infects men and children more than women, it has evolved a mechanism to increase its infection rates: the ability to pass through the placenta and infect an unborn child. This evolutionary mechanism allows the parasite to spread to as many people as possible. I think the trend that men are more commonly infected than women is a great example of the extended evolutionary synthesis idea that niche construction will be systematically biased towards an environment that is well suited to their phenotype. The trypanosome that causes Chagas prefer to invade muscle tissue, and commonly men have greater muscle mass than women. Therefore, the trypanosome tends to show more infection in men because they have their ideal
Australopithecus afarensis who existed 3.5 million years ago and a 4.4 million year old skeleton of an Ardipithecus ramidus are the closest science has come to discovering the human lineage. Shattered Ancestry an article written by Katherine Harmon discusses the remains of two hominids found within Ethiopia. These skeletal remains have created a huge controversy within the topic of evolution questioning many assumptions that have been made referencing the human lineage. The skeleton of the Australopithecus afarensis was named Lucy and was discovered in 1974. The evidence of her walking upright on her two feet essentially guaranteed her a spot in the human lineage line. Lucy was a chimplike ape that was said to walk upright making scientists believe the human ancestry was simple. The complete skeleton found in Ethiopia of an Ardipithecus ramidus named Ardi completely changed all assumptions made from scientists about the complexity of the human lineage. These remains have encouraged researches that the human line is not the only lineage to have evolved but the chimpanzee line has undergone drastic changes as well. There are many traits that researchers have always directly linked to the human lineage however since these discoveries occurred researchers are reconsidering. The recent discoveries that have shattered what has always suggested what linked a species to the human lineage have changed the certainty of whether it is possible to confidently identify the human’s last common ancestor. Majority of scientist had forgotten that there would have been many hominid species living together at one time. New theories have been suggested since scientists revealed that the foot of a hominid found called the Burtele site was found ju...
the definition of parasite, is something that hurts. for ever. this parasite, was a landmine. I had good medical attention. But once i returned home, I finally left. I wanted to leave. there were rockets, raining down in every place i looked. those rockets stole my family. we couldn't stay. so we fled. the last time i had a true education, was when i entered high school. between 2nd grade and 9th the education i had in my birth place, that wasn't any kind of education. i wanted more. and there was nothing there for me to want
Schistosomiasis is a parasite. This parasite is a worm that you get through contaminated water. Urine and feces usually contaminate the water. The worm goes in to your body and migrates to the bladder, rectum, liver, lungs, spleen, intestines and some veins. After the worm migrates to these places this is where it matures and lays its eggs. The disease has the ability to lay two thousand to three thousand eggs per day and can live for twenty years. There are five different kind of Schistosomiasis that effect humans, these different kinds are; S. mansoni, S. Heamatobium, S. japonicum, S. intercalatum and S. mekongi. There are also other kinds of Schistosomiasis that occasionally infect humans, there are; S. bovis, S. mathei, and some avian schistosomes.
According to the CDC website, there are 55,400 people diagnosed with Syphilis every year and 322 reported cases of congenital Syphilis in 2012 (6). Treponema pallidum 3 Mechanism of Pathogenesis Treponema pallidum is transmitted sexually through oral, anal, vaginal intercourse and from mom to baby during pregnancy or during birth (1). The human host is the only natural known for Treponema pallidum, but testing can be done on rabbits for primary and secondary infections (8). Once this pathogen enters the body it starts to multiply causing inflammatory responses and the development of chronic sores (8). How Treponema pallidum causes disease is by resisting ingestion by macrophages, causing the antigens to bypass opsonization, which leads to the infection of syphilis (8).
The objective of the host is to "escape" from the pathogen. This can be done through the use of the immune system or by quickly dying. When a host dies with the pathogen still inside the pathogen dies as well. Resistance to invaders evolved as a result of the development of the mechanism of immunity. The development of immunity depends on the recognition of differences in chemical structures of substances.
Human characteristics have evolved all throughout history and have been manipulated on a global scale through the use of science and technology. Genetic modification is one such process in which contemporary biotechnology techniques are employed to develop specific human characteristics. Despite this, there are a countless number of negative issues related with genetic modification including discrimination, ethical issues and corruption. Hence, genetic modification should not be used to enhance human characteristics.
Darwinian medicine is a radical approach that considers why evolution has not “freed” humans from disease. Traditional medicine, for example, would examine who contracted a cold, why, and how to treat the symptoms. Evolutionary medicine examines the interplay between virulence, transmission, natural selection, and evolution in an attempt to understand why anyone would catch a cold.
This paper tells about different methods as to which parasites enter the body. Each parasite is unique as to what problems they cause or diseases they carry. Some of these parasites can prove fatal unless treated, and if they are not treated carefully, they could still complicate an individual’s health. This paper also includes the places these parasites thrive and as to how to treat these parasites. Although most of these parasites are treatable, the treatment required is completely dependent upon what stage the parasites have progressed to. Some parasites are accompanied by a disease and are therefore not the primary health risk of getting infected. Nevertheless, if left untreated all of these parasites can host the body for large periods of time, which can lead to prolonged illness. Most of these parasites are found in third world countries, but under the right conditions can be found in the United States of America.
There is little at face value that would alert an educated individual to the severity and the danger of Syphilis – the bacterium which causes syphilis, Treponema pallidum, appears as nothing more than a simple bacterium. The bacterium is spiral in shape, and is classified as Gram Negative (meaning that the bacterium lacks a thick layer of peptidoglycan in its cell wall). Syphilis infects it's victims through a limited number of ways – the most common way, however, is by entrance through chafed, cracked skin and through mucous membranes. Because of this, Syphilis is so effectively transmitted through sexual contact and sexual activity that it is primarily known as a Sexually Transmitted Infection (STI). However, Syphilis does not limit itself to only the aforementioned modes of transportation. The disease is also effectively transmitted through blood transfusions, not to mention the passing of Syphilis from mother to child in the womb during pregnancy (CDC 2007).
This disease may be on the brink of being eradicated entirely but that doesn’t stop it from being one of the grossest things that anyone has ever seen. The parasite enters the body via unsafe drinking water. When people drink water infected with water fleas that have have been hosting the larvae of the parasite. There are no symptoms, to begin with, but about one year later, blisters on the feet or legs begin to develop and then the adult fully developed worm crawls out of the host body over a period of a few weeks. It’s said that the pain is intense and can incapacitate a person for weeks at a time. The pain can also continue for months after the infection. The parasite needs to infect a person at least once a year in order to continue. There were an estimated 3.5 million cases in 1986 but the disease has been greatly reduced over time and only 22 cases were reported in 2015. This disease will probably be the first parasitic disease to be completely eradicated in humans.
In class we watch a clip called “Journey of Man” and basically the all over view of this movie was about a man named Spencer Wells and his team of scientist researching for approximately 15 years of investigating to find out our family history. They believe that they have discover some life changing information. They had this discovery for a while now but that needed time to gather up all of the facts from their research. This information that they have could transform our view on the world. They have revealed some type of time machine that has allow them to see back in ancient history. For that past ten years this man and his team have been using this time machine to gather all types of different information about the past history. This information came for just once source, blood. Many people views it as and gift from the past, but to scientist it carries the past and has a unique story behind it. A time machine hidden within us.
Are we still evolving? How do humans and apes share a common ancestor? Modern human species or Homo sapiens have shown great similarities in the physical and genetic makeup to another group primates species, the apes. Both organisms share a common ancestor dating back eight to six million years ago. Evolution means change over time. Human evolution is the process by which humans have emerged from apelike ancestors. Through sequences of mutations, genetic drift, migration, and natural selection and technology we are able to observe the amazing amount of similarities and diversity of humans to other living organisms. Humans have roamed the earth for about six million years. At least, that is from when the oldest human ancestor was discovered.
one in which the host animal can live for a long enough time for the parasite to
Evolution is the complexity of processes by which living organisms established on earth and have been expanded and modified through theorized changes in form and function. Human evolution is the biological and cultural development of the species Homo sapiens sapiens, or human beings. Humans evolved from apes because of their similarities. This can be shown in the evidence that humans had a decrease in the size of the face and teeth that evolved. Early humans are classified in ten different types of families.