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Ecology investigates the interactions between organisms and their environment. One branch of ecology looks more specifically how the environment can lead to physiological effects in individuals and populations of species. Physiological ecology studies organisms coping with environmental variation. A particular species cannot live everywhere due to energy resource limitations, physiological tolerance limitations, and interactions between resources and tolerance. These determine effects on growth, survival, and reproduction. For example, Quaking aspen (populus tremuloides) is a broadly tolerant species with northern range limits including frost effects (permafrost) and a southern range limit of drought effects. Specific physiological functions are inhibited by drought and frost. Species ranges reflect environmental constraints on energy gain and physiological tolerance. Populations respond to environmental variation through adaptation (natural selection). Populations differ across a species range. Genetic variation allows for many traits, an when new conditions occur, certain mutations may be beneficial for that species. Individuals respond to environmental variation through acclimation. They adjust their phenotype to reduce effects of environmental change.

Viruses demonstrate properties of life and properties of non-life, which makes them difficult to categorize as living or nonliving. However, they belong to both categories that ultimately places viruses in a distinct category. Living properties of viruses include having genetic material (DNA, RNA), being able to reproduce with a host cell, and capable to evolve through mutations. On the other hand, viruses associate in the nonliving group because they lack a metabolism or organelles, cannot maintain homeostasis, and do not grow and develop, which all living cells can accomplish. A virsus' most signitficant feature is the incapability to multiply without host cells. These host cells are crucial for viruses because they reproduce by attaching themselves to a specific host cell and injecting its genetic material into it. Soon after, the host cell lyses and the replicated viruses are released to proceed the same cycle, resulting in greater viral genetic material in its environment.

Traditionally, the methods used to test a mother’s growing fetus for abnormalities are highly invasive and pose a serious risk to the developing child. Due to advances in genetics in recent years, newer far less invasive procedures are now available to expecting mothers that offer equally valid, and in some cases, possibly more reliable results without the need to put the child at risk. Non-invasive prenatal screening involves taking a simple blood sample from a mother who is at least 10 weeks along in her gestation period. The blood is centrifuged to separate the blood plasma from the denser red blood cells, and what's left is a solution containing just cell-free DNA (cfDNA) fragments from both the fetus and the mother. The majority of the cfDNA will be from the mother, but for reliable results in this test, a percentage of just 4% fetal DNA is adequate. The analysis is done by looking at the proportions of fragments found from each of the child’s 23 chromosomes and looking for higher or lower than expected proportions of certain chromosomal fragments that could indicate a trisomy or chromosomal deletion. For example, finding a higher proportion of cell-free DNA (cfDNA) fragments from chromosome 21 of the fetus suggests the child is at a higher risk of being born with Down Syndrome. All this has only recently become possible thanks to advances in the speed and efficiency at which genetic sequencing can be performed. The samples of multiple patients may be sequenced at once leading to a much faster and cost-efficient way of analyzing DNA.

Acute flaccid myelitis (AFM) is a disease that nearly resembles polio in which the disease includes cold like symptoms followed by loss of muscle control and paralysis of arms or legs. Approximately sixty-two cases have been reported around the States in about twenty-two states. Scientists have slowly, but surely narrowed down suspects in which this disease could be caused by. The enterovirus D68 (EV-D68) was narrowed down to be a possible suspect. Although the evidence doesn’t completely make this assumption conclusive EV-D68 is suspected by many scientists. This enterovirus spreads through saliva and mucus and causes similar cold like symptoms and sudden loss of muscle control. Kenneth Tyler of the University of Colorado (CU) School of Medicine in Aurora reported that several strains of EV-D68 could cause paralysis in mice. EV-D68 seemed to attack nerve cells directly causing this loss of control. If the enterovirus is indeed causing the paralysis, scientists are still unsure exactly of why it is only doing so in few cases. Although there is no vaccine against EV-D68, a possible vaccine developed in China had shown positive results in mice. 

The two pieces of literature are drastically different. “Describing and quantifying interspecific interactions: a commentary on recent approaches” is a piece which argues why certain approaches to interspecific interactions are better than others using the evidence of several studies and experiments, while “Neighbor Relations within a Community of Epiphytic Lichens and Bryophytes” is a report of the study conducted by the writers John and Dale. These are two distinct types of scientific writing; one is analyzing the works of others and determining something from that while the other piece tells of its own study. Therefore, aspects of each paper are different.

I recently watched both the movie Outbreak and the movie Contagion. Both movies were incredibly entertaining. Outbreak focused on a virus that the military weaponized and covered up. They released the virus in an African village to watch the effects they then destroyed the village to make sure no one would know that the virus existed. The military failed to contain the virus and it got out and lived within a population of monkeys. This population was discovered by scientists and later brought back to the United States. Someone trying to make money from the virus smuggled one of the mokeys out of a lab and the virus mutated and became airborne once it got transferred to a human host. So then it gets out and an entire town gets infected and quarantined. They eventually make a vaccine and the townspeople are saved. Contagion is a little bit more extreme. It follows a virus that was brought from china back to the States and all over the world. It managed to infect 1 in 12 people around the world killing a vast majority of them. The movie focuses on how society would essentially crumble while everyone worries about getting infected with an incredibly infectious pathogen. At the end of the movie it shows a cut scene of how the outbreak started. Bats harboring a virus transferred it to pigs. The pigs then were slaughtered and sent out to be eaten. The chef preparing the pig at a bar in China didn’t wash his hands and was interrupted in the middle of preparing it. The chef then walks out and shakes hands with a girl who later touches her face, then comes in contact with many people traveling to many parts of the globe. It is incredible how fast a competent pathogen can spread when the perfect storm of scenarios happen.

After reading the chapters in Writing in Biological Sciences by Angelika Hofmann as well as The One Right Way to Talk Science by Jay Lemke, I learned and was surprised by a few things. I found it interesting in the reading by Lemke that he seemed to oppose the use of formality in scientific writing, or rather, encouraged the fact that science is a very “human” activity. Lemke lists even the ways that scientific writing can be too correct and too serious, which ultimately drives the attention of the reader away. He says that “these rules are a recipe for dull, alienating language. They mainly serve to create a strong contrast between the language of human experience and the language of science” (Lemke 134). I found this quote to be particular interesting because from I have always been taught in school about scientific writing, it should be as formal and serious and complexly worded as possible. However even I feel at times, even reading the scientific review article (from this week’s readings), Describing and quantifying interspecific interactions: a commentary on recent approaches by Peter A Abrams, that it fit this serious and “alienated” language description exactly as Lemke describes in his chapter. I felt that the constant use of complex wording actually made it harder to follow (without having to re-read a few times) in certain paragraphs because it was so serious. Another point I learned came from Hofmann, where she provides the difference between a scientific research paper and a lab report. Previously I had considered them to be found within the same category because they both include introduction, methods, results, and conclusion sections, however there is a difference. Both are based upon original sources of data, however lab reports focus on one particular study while research papers investigate a whole “family” of related experiments performed perhaps over a period of time. As she continues her description of lab report tips, I liked how Hofmann gives samples of good and bad types of titles (even a title page), tables, abstracts, and provides structure formats for introductions and the big picture.

Due to the neuroendocrine nature of pancreatic cancer, the researchers are interested in developing an early screening technique involving hormonal and molecular biomarkers through routine blood tests. PanNETs (pancreatic neuroendocrine tumors) are classified into functional tumors, which have symptoms related to excessive hormone secretion, and non-functional tumors, which do not secrete hormones and therefore do not exhibit associated symptoms. In functional tumors, measurement of hormones such as pancreatic polypeptide, gastrin, proinsulin, insulin, glucagon, and vasoactive intestinal peptide can determine if cancerous cells are involved in hypersecretion (Ro et al., 2013). Up to 60% of PanNETs are non-functional, which may pose a challenge to the researchers. However, 85% of PanNETs have an elevated blood marker, which may allow for further research and scrutiny of biomarkers to accomplish this goal (Jensen et al., 2009).

Work in pairs. Each pair should follow a link, briefly discuss, and be prepared to report on the reliability, validity, and trustworthiness of the site. How do you assess these characteristics?

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Birds are bipedal vertebrates that evolved from theropod dinosaurs or reptiles. They are from a new class of vertebrates known as Aves which includes all birds. They have feathers and wings. The main function of their feathers is to maintain body temperature and their wings are used for flight. To maintain balance, birds placed their body in the center of the earth so it can be over and between their feet. When landing, they come closer to the ground and slowly rises to minimize the impact. 

Most birds are arboreal, in other words, tree-dwelling species. They grip on tree branches to keep their body upright and to prevent them from falling. Birds do not have claws, but instead, they have 3 digits or toes that they used to climb up trees. They also don't have teeth but instead, they have gizzards that help them digest hard nuts shell, seeds, and insects. Birds are the only species of its kind to reproduce externally. Most birds provide parental care until the eggs hatch after that the babies are on their own. They use their acute senses to help them navigate and communicate, also, they can hear sounds and see a wide range of colors more than humans. Their brain is about six to eleven time larger than reptiles and has lateralization that resembles primate brain.