Oxadiazoles: an anti-adaptive

http://www.sciencedaily.com/releases/2014/03/140307165953.htm
(highlight and right click to go to website)

summary(summarized by the university of Notre Dame on march 7th 2014): A new class of antibiotics to fight bacteria such as methicillin-resistant Staphylococcus aureus and other drug-resistant bacteria that threaten public health has been discovered by a team of chemists. The new class, called oxadiazoles, was discovered in silico (by computer) screening and has shown promise in the treatment of MRSA in mouse models of infection. MRSA has become a global public-health problem since the 1960s because of its resistance to antibiotics. In the United States alone, 278,000 people are hospitalized and 19,000 die each year from infections caused by MRSA. Only three drugs currently are effective treatments, and resistance to each of those drugs already exists.

Relevance: This article is relevant to our study of the resistance of antibiotics to the medicines of today. MRSA is a bacteria that has adapted to many of the antibiotics that we commonly use to treat bacteria, such as penicillin. What is interesting about this new class of antibiotics is that it does not kill the bacteria, but "reverses" the adaptations to common drugs so that other drugs can treat is. It is also relevant because this new class of antibiotics is not just an antibiotic, but also is an anti-adaptive(I made that word up) 

Ancient Legged Fish

Doran Teverovsky
Mr. Mathieu
Period 2

Michelle Lograta
January 15, 2013
http://www.gmanetwork.com/news/story/343973/scitech/science/ancient-legged-fish-provides-missing-link-in-limb-evolution

Summary:
   Recently, a new fossil has been found in Canada of a type of fish, about 375 million years old, that had legs, and could possibly walk on land and water. This nine foot long fish also provided challenging to classify because it blurred the line between crocodile and fish. While this fish, named the Tiktaalik roseae, had a similar rib cage and lung structure to a crocodile, it also had gills and scales leading scientists to name it as a fish. This fish has given scientist much more conclusive proof that rear appendages evolved in water then gradually went to land. The massive pelvis of this fish was what gave it away is a walker. The pelvis was open, and was shaped for legs and possibly even a fin as well.

Connection:
    This recent fish find relates to evolution, classification, and phylogeny. Before, we were guessing as to where legs evolved, with this fish, we can much more easily place mammals and fish on the same phylogeny because of this ancestor. Also, this connects to classifying organisms, and how difficult it can be for scientists. Because this animal had such crocidillian, and fish like characteristics, people had to pool all of there resources to decide what to call the animal. This animal is a great example of how one thong leads to another in evolution, and how the slightest advantage, by getting on land first, leads to adaptive radiation in the extreme.

Human-Pathogen Coevolution

Helicobacter pylori strains that share ancestry with their human hosts are less likely to cause severe disease 

Author: Jef Akst

Source: http://www.the-scientist.com/?articles.view/articleNo/38845/title/Human-Pathogen-Coevolution/


Summary:

Helicobacter pylori is a bacterium that colonizes in the gut mucosa in nearly half the human population, causing gastric inflammation and sometimes stomach cancer. This is one of the second-leading causes of death by cancer in the world! The study of this bacterium shows that patients who contain this strain possess fewer severity of diseases compared to the distinct ancestor who had the bacterium in their body. Scientists and doctors say that this issue should be seen with both the host and microbe, or population and pathogen. After collecting samples from a Columbian Hospital with gastric cancer patients, doctors found out that the severity of the H. pylori is less severe compared to the distinct ancestors due to the evolutionary adaptation and change of humans. The idea was that if one coevolved with the bacterium, the strain becomes les and less virulent.


Connection:

This article talks about the idea of evolution and how coevolution or convergent evolution is something species, including bacterium, undergo. In this article, it shows how the bacterium Helicobacter pylori underwent coevolution with humans in different environments, causing the severity of its affects to be dampened. Another connection to the evolution unit is the idea of adaptive radiation. Due to humans adapting in various environmental conditions, humans on the African coast had a less virulent strain of the bacterium similar to humans living in the mountains. As a result, the bacterium adapted and varied itself to the environment as it was in the host, causing the severity to decrease.

Scientists discover chemical modification in human malaria parasite DNA

Katie Liu

Published: 11 Dec. 2013

Link:http://www.biologynews.net/archives/2013/12/11/scientists_discover_chemical_modification_in_human_malaria_parasite_dna.html?

The Plasmodium parasite, which causes malaria, is mutating to resist some of the most effective drugs against it. However, recent studies have shown low levels of DNA methylation in its genome could be a possible way to eliminate the parasite. The low levels are important to the survival of the parasite. DNA methylation is a biochemical process regulating how genes are expressed, which plays an important role in diseases. In humans, DNA methylation is very important. Abnormal DNA methylation has been linked to many diseases such as cancers and neurological disorders. Until now, it was unsure if Plasmodium contained methylation, but research has confirmed its low level presence in the parasite. The DNA methylation in Plasmodium is different from the ones in humans. Due to this difference, if a way can be found to shut down the methylation enzyme, then it could kill the parasite in sick people. Despite this, more research still needs to be done about Plasmodium.

This relates to what we've learned during our evolution unit. The reason why the parasite was becoming resistant to many drugs was due to the fact that it was mutating and therefore was able to have some members of its population resistant to the malaria cures. We also learned how animals also adapted to their environments similarly to the Plasmodium through adaptation and natural selection. This connects to what we've learned in our evolution unit. We’ve also learned about DNA and gene expression during our molecular biology unit, which relates back to the DNA methylation in the article.

Adelie Peguins and Emperor Penguins

Have A 100% Success Rate for Feeding 

in Recent Studies

http://video.nationalgeographic.com/video/news/animals-news/adelie-penguins-cameras-vin/

Summary written by Marshall Grant

            Today, scientists from all around the world travel to the thick depths of the Antarctic to study the behaviors of the many species of animals it is home to. We know a lot about the surface interaction of penguins as part of a flock on land through camera study and in-field analysis, but never did scientists ever try to study the interaction of penguins on other organisms in the freezing antarctic waters, until now. Many recent SCUBA divers have filmed the breath taking movements of penguins under ice caps. Though many species of penguin are endangered, the question rises about their success rate while fishing.

           A recent study carried out by a Japanese Research Team, have tagged and applied small long range cameras on the back of Adelie Penguins to count and gather data on feeding rates for the penguin species. The same process was carried out by an American Research Team on Emperor penguins to gather their success data. The results pooled by both teams was astonishing. Adelie Penguins were able to capture 2 krill organisms per second and 14 fish organisms every 20 seconds without failing to capture or miss its prey on the approach. The same held true for the Emperor Penguin where it went 100% catch rate in 3 hour feeding period.

         Why is this important? Further study is providing us with a better understanding of the feeding behaviors of these agile birds of the Antarctic. It also generates a greater question towards the important of conservation of fish and krill species in order to preserve the Penguin population, as they play a vital role in the ecosystem of the Southern Ocean.

Connection:

Since the topic we cover is animals, a penguin fits the category. In biology class, we are better understanding how animals came to being, and the adaptations that help them accomplish such in certain environments  The Penguins of the Southern Ocean are a perfect example of how big our ocean is and how little we have explored from it. Learning more from Penguins and creatures of our world's oceans will better help us as a society preserve and protect the resources and species of this great planet of ours. Further research on animals like the Penguins and what we study in biology class will open new doors to evolution, research, discovery, and innovation.

How the Ocean Loses Nitrogen

How the Ocean Loses Nitrogen: Scientists Identify Key Factor That Controls Nitrogen Availibilty In the Ocean

Feb. 24, 2013
Tim Kalvelage
http://www.sciencedaily.com/releases/2013/02/130224142723.htm

Summary: 
Recently a group of scientists from Institute for Marine Microbiology in Bremen and also some from the company GEOMAR went to the South Pacific Ocean and they found some interesting data. They concluded that decaying algae controls nitrogen loss from the ocean. The ocean is rapidly filling with more nitrogen then normal. This means there is less oxygen and the nitrogen gas from the ocean is then escaping into the atmosphere which can contribute to global warming. Also, the lack of oxygen and increase of nitrogen in the ocean could change what lives in the ocean. We could see in the coming years, the increase in populations of organisms which live in the none/minimal oxygen zones of the ocean. Anaerobic bacteria converts the fixed nitrogen in the ocean to nitrogen gas which is released into the atmosphere by processes such as denitrification and anammox. 

Connection: This discovery connects to our study of microbes and also the nitrogen cycle. Microbes in the water fix the nitrogen. Then, anaerobic bacteria take the fixed nitrogen and convert it into nitrogen gas which can then exit the ocean and be released into the atmosphere. The ocean is a one of the major nitrogen holders which we talked about earlier in the year. Once the nitrogen is released into the atmosphere it could contribute to our problem of global warming. Also, this story connects to adaption because the sea organisms will have to adapt to a changing ocean environment. There will probably be an increase of anaerobic organisms in the ocean as more nitrogen fills the ocean.

Wrinkled Fingers are a Evolutionary Advantage

http://www.news.com.au/lifestyle/home-garden/why-do-fingers-wrinkle-in-water/story-fneuz5ql-1226550179190

Summary: Scientists are now researching the possibility that the fact that our fingers wrinkle up when they get wet could be an evolutionary advantage. Wrinkled fingers make it easier to pick up wet objects which could have allowed some humans to easily pick up food that was located in the water. They experimented with people who had submerged their hands in warm water for thirty minutes and those whose hands were completely dry. They found that wrinkly fingers did not help to pick up dry objects, wetter objects could be picked up much faster.

Connection: Our fingers wrinkling in water is an evolutionary change. It relates well to the evolution unit and easily shows how something seemly useless can be used in many different ways. Scientists have not mentioned where or when they think this evolution occurred but it has become a trait of all humans.

Snakehead Fish Destroying Ecosytems in U.S.

R. Kayne
(No date of publication given)
http://www.wisegeek.com/what-is-a-snakehead-fish.htm

Summary: Recent studies show that a new species of fish introduced into America's ecosystems is dominating the food chain in the water (and sometimes on land) and rapidly increasing in population size. These fish are called snakeheads. Snakeheads look a lot like eels with a head that looks like a snake. These fish can also breath air and can live on land for a short period of time. Snakeheads are huge predators and eat small mammals and fish its size. It has been said that in Asia a snakehead even ate a human. These fish came from Africa and Asia and have been supposedly introduced to U.S. waters by being freed from food markets. Snakeheads are starting to dominate U.S. waters because they are extremly adaptable and reproduce rapidly. Also, snakeheads don't have any natural predators in the U.S. so the population easily grows. This invasive species threatens to wipe out other fish populations in the U.S. and needs to be controlled. Some forms of control include: fishing competitions to catch the most snakeheads and cooking contests involving the snakeheads.

Connection: Snakeheads are a perfect of an invasive species which has been released into the U.S. and has terrorized its surroundings creating an imbalance in the ecosystem. The snakeheads also relate to our talk of evolution because they adapt from generation to generation to survive in all different types of water in America. This species is like any other invasive species, perhaps Purple Loosestrife, which outcompetes other plants and increases in population rapidly.

Are Humans Still Evolving?

Jack Foster P3

Darwin published his book The Origin of Species in 1859 and ever since then it has been a well accepted fact that natural selection of animals causes certain species to evolve and adapt based on their environment. Many people know and understand this but are humans exempt from evolving? Have in a way beaten the system where are mortality rate has skyrocketed so high that even those with non ideal genes can still survive and live despite not being able to many centuries ago? Although in short the answer is yes we are still changing one example is how many years ago almost all humans would be lactose intolerant after infancy. Now a days it is the opposite being that the majority of people can digest lactose. Many populations used dairy farming as a main source of nutrients so over time people have apapted and changed due to their environment. Also many medical and technological advances have let us saved the lives of those that would've been deemed lost in the past. This trumps natural selection and lets everyone get a fair share of life rather than just the most fit. Although this doesn't completely cancel out natural selection as many dominant traits that are deadly can destroy a population because it i s very likely that it will be passed on but those who are homozygous recessive will still be able to thrive. Many have come to believe that humans will not adapt based on how the world changes but rather how we change the world. There are no other species exactly like humans that have the power to change the earth as we know it. This could either lead to our own demise or give us hope to change ourselves for the better in future years.



Bootle, Olly. "Are Humans Still Evolving by Darwin's Natural Selection?" BBC News. BBC, 03 Jan. 2012. Web. 09 Jan. 2013.
http://www.bbc.co.uk/news/science-environment-12535647

Odd, Ancient Bird Had Sharp Teeth

By Tia Ghose
Published January 7, 2013
http://news.discovery.com/animals/odd-ancient-bird-had-sharp-teeth-130107.html

Summary:  A fossil skeleton of a bird called Sulcavis geeorum was found in China.  This bird lived 125 million years ago and had strange teeth.  Scientists think that the bird used its teeth to eat hard shelled insects, crabs, or snails.  Birds no longer have teeth, however they do carry the genes for teeth.  Some believe that birds evolved to having beaks because they are lighter and therefore easier to fly with.  This toothed bird looks very similar to the modern-day songbird, the only difference being that songbirds do not have teeth.  A lot of fossils have been found from the time period of the toothed bird over the past 15 years.  Scientists hopefully will continue to find more so they can get more information about the Sulcavis geeorum. 

Connection:  This article connects to our study of evolution.  This specie of birds has evolved from having teeth to beaks.  This is partly because birds eat different things now but also because beaks are easier to fly with.  Birds have adapted to their surroundings.  There are now different things for them to eat and they have different predators and organisms living around them.  This specie was able to change through natural selection.  The birds with the beaks and no teeth were better suited to their environment and were able to survive and reproduce. This article also relates to genetics.  Birds may not show the trait of teeth but they do carry the gene for them.      

Giant Galapagos tortoise species may not be extinct

Jack Billings
http://usatoday30.usatoday.com/news/world/environment/story/2012-01-06/galapagos-turtles-extinct/52467768/1
Published: Monday January 9, 2012
Source: USA Today
Author: Elizabeth Weise

Summary:
When Darwin visited the Galapagos islands in 1835, one of the animals that helped him develop his theory of evolution was the tortoise. One species he described was the Chelonoidis elephantopus which lived on Floreana Island and was thought to have gone extinct within 10 years of Darwin’s expedition due to whalers who hunted them for food. Recently, researchers did DNA testing on 1,600 tortoises on Isabela Island, and found 84 which were direct offspring of the Chelonoidis elephantopus among the Chelonoidis becki natives. They did DNA testing on the shells of tortoises in museums (where the only known Chelonoidis elephantopus were) to confirm that the 84 tortoises were in fact descendants of the Chelonoidis elephantopus. Because the length of these giant tortoises lives, these individuals could be the grand kids or even direct offspring of some the the tortoises Darwin saw on his expedition. This discovery wasn't made until now because Isabela Island was never settled by humans for its lack of fresh water and because of the difficulty of getting blood samples from these 400 pound tortoises. No pure-bred Chelonoidis elephantopus tortoises were found, but scientists plant to create a breeding program to back-cross the hybrids to make a population closer to full-blooded Floreanas that could be used to repopulate Floreana Island.

Relevance:
This connects to our units on heredity, molecular genetics, and the evolution of life. The article relates to heredity because it discusses selectively breeding the tortoises to obtain the pure-bred forms of the Chelonoidis elephantopus tortoises (which have bred with the native Isabela Island species). It relates to molecular genetics because the researchers had to use DNA testing to determine what species were on Isabela Island. It relates to evolution because (much like Darwin’s finches) these tortoises probably have a common ancestor from which they have adapted to their new, isolated environments. These isolated environments have cause them to evolve through genetic drift and natural selection. Gene flow is also shown when the two species of tortoises cross-breed on Isabela Island.