Landfillharmonic! This is recycling!!!

This is absolutely amazing!!

What's in your eye? Is that a fibula?!?

Scientists have determined that a California women has bone fragments growing in her eye because her plastic surgeon used abdominal stem cells...

"Surgeons isolated mesenchymal stem cells from her abdominal fat—cells that can become bone, cartilage, and fat, among other types of tissue—before injecting them into the skin around her eyes."

Read the article and comment in several ways. Biology students can comment upon how this reflects differentiation as one of the characteristics of living things. AP Biology and anatomy students can reflect upon how the use of calcium hydroxylapatite might have affected the mesenchyme cells. Research and see if this causes an epigenetic change.

Winthrop coach Pat Kelsey

This has nothing to do with science, but it caught my attention the other day. I truly believe what he is saying, and love the passion with which he says it!

Sex ratios, hormones, and livestock farms

This Scientific American article reviews research conducted that identified  that streams near livestock confinement farms have varied sex ratios (not 50/50).

"Purdue University researchers raised fathead minnow embryos in water taken from two Indiana streams that are contaminated with natural and synthetic hormones from manure spread on fields. The embryos turned out 60 percent male; fish typically are born with roughly equal numbers of males and females."

What do you think about their research? What can be done about this? Does this affect your?

The area with the most biodiversity - How are we doing?

The following video clips shows footage from what scientists believe are the areas of the world with the most biodiversity. With our recent visit from Wayne Talbot, how do think we're doing with biodiversity around us? What can we do to improve?

How old are you?

Scientists have many ways of finding out how old organisms are. One of the most interesting is radiocarbon dating. This is shown in the following Instant Egghead video clip from Scientific American. After watching the video comment upon what you think about the dating method and whether it's reliable.

Cancer, chemotherapy, and mitosis

In biology we're learning about chromosomes, the cell cycle, and mitosis. This video ties them all in together and expands it to include the very serious topic of cancer. Give it a watch and comment on how cancer ties in with Ch 8.

Microchimera - a little bit of others in us!

Scientists have known for some time that there are human chimeras. Humans that contain DNA from other humans (undeveloped twins usually). The name chimera comes from a mythological creature seen above.

Now scientists have discovered several cases of microchimerism, a situation in which individual cells (genetic chimeras usually have entire tissues composed of different sourced DNA) from other sources are found in the body. The most common situation of microchimerism seems to occur between mother and child.

What does this say about epigenetics and our immune system? Identify what you think about the possible links between Alzheimers and these foreign cells.

Happy Thanksgiving!

Another Instant Egghead from Scientific American.

What science that we've covered did you find in this video clip?

Keep those drugs out of the waterways

It is well known (especially thanks to the P2D2 program) that there are too many drugs in the nation's waterways. This article highlights the effects those drugs are having on fish.

Note, as you read this article that the research is based on drugs that have already passed through the systems of humans and entered the waterways through the sewage treatment systems. It's possible that might be the next step for the P2D2 program.

Anatomy and AP Bio students, look at this quote from the article and comment upon it.

To find out more, Rearick compared gene expression in estradiol-exposed and unexposed fish. He found a significant increase in the expression of genes for the neurotransmitter dopamine in estradiol-exposed fish, suggesting that something might be occurring in their developing brains.
Klaper took a similar approach in her investigation of fluoxetine effects in fathead minnows, finding a cascade of gene-expression changes in the male minnows' brains as the dose increased. "I'm in the process now of trying to figure out the [physiological] pathways these might be involved in," she said.

Biology students, read the article and comment upon the scientific method being used, the ecology being studied, and how the effect of drugs on fish affects humans

More about antibiotic resistance

I have had several posts before about antibiotic resistance and now there's more research into it. This time the research focuses on the urine of cattle. That's right, bovine pee! Read the article and see what kind of research these scientists are doing?

What's your opinion of having 80% of all antibiotics in the United States being given to livestock?  Comment on the research and what they could do to expand. What else could they study to learn more about antibiotic resistant bacteria?

Otzi the Sardinian?

from: http://www.livescience.com/24666-otzi-iceman-mummy-life-death.html

The mummified remains found in the Alps of a man named Otzi has been a staple of science books for many years now. Scientists have used a variety of forensic and archeological tools to reconstruct his life. Scientists have now identified which Europeans he is most closely related to according to his DNA sequence and it is the people of Sardinia, shown in the map below. Read through the articles and and come up with a list of the forensic tools used to identify parts of Otzi's life.

from : http://en.wikipedia.org/wiki/Sardinia

Giant Roman!

National Geographic recently published an article identifying that the bones of person with gigantism had been discovered. The person was between 198 and 204 cm tall. This would have put them more than 30 cm tall than the average Roman citizen.

"To find out if the skeleton had gigantism, the team examined the bones and found evidence of skull damage consistent with a pituitary tumor, which disrupts the pituitary gland, causing it to overproduce human growth hormone.
Other findings—such as disproportionately long limbs and evidence that the bones were still growing even in early adulthood—support the gigantism diagnosis, according to the study, published October 2 in the Journal of Clinical Endocrinology and Metabolism."

Using the bold print from the article copied above, identify what the scientists were looking for in the bones that they used as evidence for gigantism.

It isn't terribly strange to have a person that is 200 cm tall at this point in time? What changes have occurred that caused changes in height? 

Why do paper cuts hurt so much?

In a video clip taken from Scientific American's Instant Egghead, we can learn why papercuts hurt so much.

Maybe I'll take the train...

This Discover magazine article identifies that a pandemic could spread very easily through airports. They used computer modeling of millions of flight itineraries and crunched the numbers. The listed the top/worst 10 airports. Most of the worst carried a large number of international passengers, since that would spread disease most easily.

The 1918 flu pandemic was also spread by mass transit, although it was certainly a slower version. There were more cases of the flu also rail lines at that time.

If an infectious disease were to suddenly break out, what could be done to stop or slow it using this information?

It's all in your mind.

There have been several studies conducted about the effect of wind generators. With the close proximity of the wind farms in the area, there have been some in the area to bring up these symptoms. This article identifies the lack of scientific basis for many of these claims and goes so far as to identify that most of them are of a psychological root, not physiological

What do you think? Do you agree that most of these symptoms are psychological or could there be a possible physiological mechanism for them?

Greatest American Hero!

Several years ago when I was teaching General Science I came across some video footage (actually a music video by a group called Boards of Canada, and only the first two minutes are of any consequence) of Joseph Kittinger's record setting skydive. Note that as he falls the sky is actually mostly black, not the blue that we're used to! He is actually falling at a speed close to the speed of sound, although he felt no wind due to the fact that there's almost no atmosphere where he was at.



.

I was so taken by the bravery shown by this man that I looked up a little more about him. His story is incredible. He not only was a test pilot, and was a part of the first testing for the space program (that's where is skydive jump came in), he also fought three tours in Vietnam and flew 483 missions. He was captured and spent 11 months as a POW.

His name is back in the news as his freefall record is about to be broken (Update: it was shattered on October, 14, 2012) by Felix Baumgartner. You can read about Joseph Kittinger and his record setting skydive in a National Geographic article.  Some more pictures of him in preparation and as he fell can be found here.

Read the articles and comment about what science gained from his experience. Also comment upon what science is learning from Felix Baumgartner's freefall.

Stopping influenza epidemics?

Each year the flu kills approximately 36,000 people (mostly elderly) and accounts for an unbelievable amount of work and school absences. In 1918-1919 a flu pandemic (and epidemic of global scale) traveled the world and killed an estimated 50 million people.

 

Obviously the influenza virus is an important one for scientists to work on limiting its effect. Scientists and medical professionals have focused on making sure the elderly have been given their yearly flu shots (not a vaccine, but as good as can be done with a virus as variable as the flu virus). 

A new look at the problem identifies that the elderly, while most often affected, are not the main problem in spreading the epidemics. Children and schools are and should be the target says new research based on computer models.

Computer-modeling studies suggest that immunizing 20 percent of children in a community is more effective at protecting those older than 65 than immunizing 90 percent of the elderly. Another study suggests that immunizing 70 percent of schoolchildren may protect an entire community (including the elderly) from flu. Schools are virus exchange systems, and children are “super-spreaders”—they “shed” more of the virus for longer periods than adults.

Read the whole article. What do you think? Should we have school wide vaccinations? Are there any ethical issues associated with this? 

Got gas?

I've always wanted to have a million dollar idea, or even a billion dollar idea. I think this Cuban farmer has a great idea to gather the methane that comes from his pigs' feces for use in his house and his neighbors' houses. If someone were to take this one the large scale of the confinement farms in the United States, it definitely could be a billion dollar idea!

Lions, tigers, mitochondria, oh my!!!!

I came across this article I found on Discover.com about the endosymbiont hypothesis. Scientists believe that this may be occurring as we in real time (so to speak with a Green Alga (eukaryote) and nitrogen fixing bacterium.

 

Check out these links for endosymbiont hypothesis

• IUPUI
• Evidence
• Lynn Margulis

Chromosomes, Genes, DNA

Scientific American has another excellent Instant Egghead, this time about the organization that occurs within our genetic structure. It is a great review for all my students.

Brain Freeze

When you get a brain freeze, where does the pain come from? These scientists think they have discovered it!


Comment on this by identifying whether you would volunteer for this research (all the slushies you want!) and to tie it in to the curriculum, what does this have to do with homeostasis?

GM labeling

This is a topic that has been covered in the last year, and will be covered again this year! Should food products that contain genetically modified ingredients be labeled as such. As it is right now, there is no labeling except the voluntary labeling by companies that want to identify that their products are GM free (see an example of Silk Soy Milk, NonGMO project).

There's a ballot initiative in California (Proposition 37) which would require all GM foods or foods with GM ingredients to be labeled as such.

"Labelling would certainly have far-reaching consequences: around 94% of the soya beans and 88% of the maize (corn) grown in the United States is genetically engineered to resist herbicides, insect pests or both, according to the US Department of Agriculture. The plan could affect tens of thousands of brand-name products, and food manufacturers."

Large agribusiness companies and some food manufacturers have put forth money in the fight against the labeling initiative. 

What do you think? How would you vote if you were a California resident? How will this affect you? 

The Jack Youngblood of the 400m??

I have mentioned in anatomy class many times that the fibula is a non-weight bearing bone. Jack Youngblood played the entire 1979 playoffs including the Super Bowl and the useless Pro Bowl on a broken left fibula. I cannot imagine the pain involved with this.

Manteo Mitchell of the USA 4 x 400 team may have surpassed this amazing feat in the 2012 London Olympics. While Jack Youngblood was able to be taped and probably take painkillers in preparation for the games, Manteo broke his leg during the race. He completed his leg (another 200 m) on the broken fibula. He's amazing!!! 

Ecology of rotting logs

I enjoy walks through woods, and strangely enough rotting logs have always fascinated me. I have loved to walk up them like a balance beam, kick the fungi growing on them, and occasionally just break them! This Discover blog post identifies the ecology of the rotting logs. Look for mutualism, commensalism, and competition in here. It also does a nice job of tying the fungi in with the coal that was common in this area. It's a pretty neat article.

As I camp I also notice that many campsites have identified that fallen wood shouldn't be burned because it's important for the health of the forest. It allows the forest to regenerate itself.

The Dating Game - Increasing chemical reactions?!!

I have to start off with a hat tip to Mr. Barlow's Blog (an excellent educator blog with lots of great stuff!). I have his blog on my RSS feed and he has some awesome stuff, including this video!

This video from TedED is a great recap of speeding up chemical reactions.

Off topic - Is algebra necessary?

This editorial by Andrew Hacker written for the New York Times has sparked something that I have wondered over the last few years. It seems as though we push algebra even into the elementary levels before students are ready. Plus we force many of our students to take math that they will never even remotely use in their adult life. I'm not against adding rigor for our students, but shouldn't it be appropriate for the student?

Colleges use math as a bar for students to hurdle, one that might be too high for some.

"California’s two university systems, for instance, consider applications only from students who have taken three years of mathematics and in that way exclude many applicants who might excel in fields like art or history. Community college students face an equally prohibitive mathematics wall. A study of two-year schools found that fewer than a quarter of their entrants passed the algebra classes they were required to take."

It's possible to take these students and give them the math that they need, based on the job they will take after high school/college. This is a great example. 

"Even in jobs that rely on so-called STEM credentials — science, technology, engineering, math — considerable training occurs after hiring, including the kinds of computations that will be required. Toyota, for example, recently chose to locate a plant in a remote Mississippi county, even though its schools are far from stellar. It works with a nearby community college, which has tailored classes in “machine tool mathematics.”   

"...But a definitive analysis by the Georgetown Center on Education and the Workforce forecasts that in the decade ahead a mere 5 percent of entry-level workers will need to be proficient in algebra or above.

On the flip side, since elementary teaching has done away with much of the 'drill and kill' assignments, students have no basis upon which to fall back when doing algebra. I encounter high students on a daily basis in which multiplication and division are as foreign a concept as calculus. These students cannot complete an algebra problem because they never learned the basic skills. The problem is NOT algebra! 

Update
There have been a few responses to the editorial in the New York Times since then. This is from a blogger for Scientific American and I think she makes a great point here:

"Mathematicians are recruited by hedge funds, consulting firms, and technology companies not because they already know how to balance portfolios, what the best corporate strategies are, or how to optimize user interfaces, but because their mathematics degrees indicate experience and acuity at problem solving (bold added). It’s easier for companies to teach someone with a strong mathematics background how to do their specific work than to teach someone who knows the company business how to solve problems. And, like it or not, algebra is one of the first places students start to learn these problem solving skills." 

Update 2

One more blog post from Scientific American. It has a great quote from a Japanese educator as they made a shift away from math in the mid-1990's. 

"This kind of experiment has already been done. We need only look to our Eastern neighbor, Japan, for a glimpse of the kind of future this could bring. Caltech string theorist Hirosi Ooguri minced no words when he reacted to Hacker’s article on Facebook:

“This is extremely dangerous, and we should not just laugh at it. A similar argument led the Japanese Government to reduce elementary, junior high, and high school math education significantly during the 1990′s. In the past few years, the Government realized the mistake and is trying to reverse it. Unfortunately, a generation of children missed opportunities to get decent education in mathematics, and I am afraid that its negative effects will be felt for many years to come.” (Ooguri graciously granted permission to quote him).

He is referring to the yutori kyoiku (“room to grow”) educational policy that dramatically altered the elementary, junior high and high school curricula in Japan. It sounds great on paper: convinced that traditional rote memorization is insufficient in a 21st century world, Japanese students now were encouraged to develop individuality and initiative, and foster critical thinking and problem solving. The number of classroom hours was reduced, and so was the amount of required math. “Japanese had good basic study skills, so the idea was to add the more individualistic things that westerners have on top of that,” psychologist and author Hideki Wada told the Financial Times."

 

Let me know what you think.

Live to 100?

My paternal grandma lived to be 98, while my maternal grandparents lived to be over 90 before they passed. After watching this video, I think I might have a chance to live quite a long time! I did find this too though! "Findings based on millions of deaths suggest that shorter, smaller bodies have lower death rates and fewer diet-related chronic diseases, especially past middle age. Shorter people also appear to have longer average lifespans." UGH!

Plant Defense

We're all familiar with plant defenses such as thorns and toxins. I had a nasty case of poison ivy two years ago that I don't wish to repeat. This article identifies how barley fights off fungus using a protein in the cell that causes cell death. It's a fascinating situation of cell communication and programmed cell death to 'starve' the fungus.

21st Century Skills

Do you feel like this school (or any school) is getting you ready for your future? This article from CNN addresses the 21st century skills necessary for students to get a job.

Do you agree? Disagree? How well do you think you are being prepared for the future?

Discuss.

Does diet soda cause a bigger waist size?

This MSNBC article has this quote

In one study, people who drank two or more diet sodas a day had five times the increase in waist circumference over a 10-year period compared to people who didn't drink any diet soda. 

The research is also referenced here:

For one study, researchers at the center followed 474 diet soda drinkers, 65 to 74 years of age, for almost 10 years. They found that diet soda drinkers' waists grew 70 percent more than non-drinkers. Specifically, drinking two or more diet sodas a day busted belt sizes five times more than people who avoided the stuff entirely.

What about this study?

The other study may hold the answer. In it, researchers divided mice into two groups, one of which ate food laced with the popular sweetener aspartame. After three months, the mice eating aspartame-chow had higher blood sugar levels than the mice eating normal food. The authors said in a written statement their findings could "contribute to the associations observed between diet soda consumption and the risk of diabetes in humans."



What do you think of this? What other reasons could  cause this? Make sure you read through the entire article and identify the good and bad about the research. 

Update - New article from NBCnews.com

Knuckleball

I love knuckleball pitchers. The knuckleball was one of the first pitches my dad showed me how to throw, and it was one of the first I showed my son. I always thought that it would have been a good vehicle to getting into the pros! Seeing the success of R.A. Dickey has me thinking I should start practicing it again, who knows? Here's a little about the physics of knuckleballs and why they are so unpredictable. I'm not familiar with the pitcher in the clip below, but he has some nasty movement on his knuckleball.

Diet soda's affect on the brain

Diet soda has an effect on the brain's calorie counting region. This Science News article gives a synopsis of research conducted on both humans and rats.

What do you think of this research?

Science by Disney

This YouTube clip about animal pollinators is very interesting. It also happens to come from Disney!

It's good to be dirty?

There are quite a few scientists that have supported the hygiene hypothesis in one way or another. This is another article that identifies that a perfectly clean and bacteria free life style is actually not the most healthy situation. other article

"That finding is a new twist on the hygiene hypothesis, the idea that contact with bacteria early in life is crucial for the development of the human immune system. Skin microbes tied to the diversity of the natural environment seem to teach the body to calm allergic responses, researchers report online the week of May 7 in the Proceedings of the National Academy of Sciences."

The other article also identifies that the recent increase in allergies in children may be due to the lack of biodiversity in the microfauna.


What do you think of these hypotheses?

Can organic farming feed 7 billion people?

This blog post/article from Scientific American identifies the benefits and negatives of organic farming vs. conventional farming.

It is identified that organic farming produces lower yields ..."organic agriculture delivers just 5 percent less yield in rain-watered legume crops, such as alfalfa or beans, and in perennial crops, such as fruit trees. But when it comes to major cereal crops, such as corn or wheat, and vegetables, such as broccoli, conventional methods delivered more than 25 percent more yield."

Is it worth it to have lower yields if it comes with a better environment? Does organic farming improve the environment? What are your opinions?


"Conventional farming requires knowledge of how to manage what farmers know as inputs—synthetic fertilizer, chemical pesticides and the like—as well as fields laid out precisely via global-positioning systems. Organic farmers, on the other hand, must learn to manage an entire ecosystem geared to producing food—controlling pests through biological means, using the waste from animals to fertilize fields and even growing one crop amidst another." 


Are modern farmers, or those who will work in the agriculture industry prepared to move to a more organic approach?

Killing Nemo?

I often joke with my students how much of their scientific knowledge (right and wrong) is based in the Disney movies. This article from Scientific American identifies how salt water aquaria are actually contributing to the decline of coral reefs and the first that live there. Many people that maintain salt water tanks think of themselves as helping to save species from coral reefs, but much like the dentist from Finding Nemo, may actually be doing more harm than good.

What do you think? What can scientists do? What can you do?

Caffeine's effect on work ethic

Science News has an article about how rats are affected by caffeine. Scientists divided them into worker rats and slacker rats based on their characteristics. Slacker rats are affected quite differently than worker rats. Read and comment!

Pop = bone loss, flame retardant chemicals, hormone interference. Really?

The Today Health website has an interesting post about 5 reasons that you shouldn't drink a lot of pop, or soda if you're from farther north. Some of the reasons are chemicals that interfere with hormones in your body, accelerated bone loss, chemicals that have flame retardant properties, and some potential (in lab animals) cancer causing chemicals.

Read the article and let me know what you think and whether these risks are the result of people finding fault in minor matters or whether you think pop is a health risk. What studies could be done to find answers more conclusively?

Tumors evolve?

Scientists have determined that there is a significant amount of mutations within the cells of a tumor. They have determined that different parts of tumors are significantly different from each other. This could be very helpful in finding different treatments and hopefully more of a chance for cures.

So many things to comment upon. Have at it!

Marijuana affects memory!

Any student that has ever been in a health class knows that marijuana affects memory. Scientists have determined that the memory loss has less to do with the affect of the THC on the neurons than it does on the neuroglia. Those 'helper' cells have THC receptors and they are certainly affected.

AP Biology and anatomy students, this article is especially pertinent to you as we covered both the receptor molecules and cell signalling in AP Biology and neuroglia was a topic covered in anatomy.

Can PE change my DNA?

While exercise cannot change the DNA a person has, it certainly can have an effect upon what genes are turned on and off. Researchers have found that exercise has an epigenetic effect upon the DNA. Click here for the abstract of the research. Scientific American has a podcast about the same thing

AP Biology students can take this information and expand upon it based on what we learned in class. Biology students should think about how this can be used and what might occur with it in the future.

Exercise yields more mitochondria in the brain?

Researchers have long known that exercise is good for more than just muscular and cardiovascular health. It also can make a person's brain function better. Using mice as subjects they followed this hypothesis. 

Some questions to ponder as you comment: Why are the mitochondria so important in this research? How can the tell the mitochondrial DNA and nuclear DNA apart? How is this an example of homeostasis? How could this information be used to improve school performance?

Fungus eats plastic!

Yale researchers identified a fungus with a rainforest habitat that has enzymes that are able to breakdown polyurethanes, the main component of plastic. As it is right now, nothing else is able to do this work and much of what fills our landfills are plastic or plastic based products. This fungus is also anaerobic, so it would be able to do its work in the low oxygen conditions of landfills.

What do you think of this? How should scientists procede? Are there any dangers associated with moving too quickly with research of this kind (thinking of biotechnology and genetic engineering)?

Frostbite on Piddy Pads?

Why is it that dogs don't get frostbite on the pads of their feet? That's pretty tough skin, but in the cold arctic winter, or even the relatively mild winters of the Midwest, dogs don't get frostbite or even suffer much if any damage to their pads when outside. Researchers have some up with a reason why they can MAINTAIN HOMEOSTASIS in the exposed regions of their pads. It has to do with a phenomenon called countercurrent exchange. This is something that is relatively common in different animals for heat exchange (like the dog's pads).

Read the article and comment upon the research and what you think they'll find if they look in other species (think both cold climate and hot climate species). Also identify some other ways that organisms use countercurrent exchange. One more, see if humans have used this in any inventions and comment upon that.

Illness - Taking one for the Team!

This Discover magazine blog post explains why humans (and other vertebrates) are not affected the same way by the same virus. I have often wondered why some people would get very sick from a virus that hardly affects someone else. My dad would often say 'because we're from hearty stock', but I didn't really believe it. This article explains it much better!


What this study found was that viruses tend to evolve so that they target mice with specific sets of MHC proteins. Once a virus had evolved to wreak havoc in mice with one set of MHC proteins—possibly by changing its own molecules just enough to avoid notice by those particular proteins, or some other work-around—it had a really hard time infecting mice with a different set of proteins, which, of course, could still sniff it out just fine.

Have you experienced this? What does this reinforce about what you learned earlier this year about viruses and how they infect cells? How can scientists use this to improve medicines?

GMO Debate

Take some time and read and look through the Livebinder composed for this (I'll try to add new sites as we find them). Determine your opinion of the use of GMOs for several situations.

• Agricultural use for animal feed or ethanol
• Agricultural use for human consumption
• Medical uses (pharmaceutical and gene therapy)

There are a few other articles to look at as well: Super strong silk from GM silkworms, Monsanto quits selling GM corn in France, Glyphosate's affect on soil, Round up Ready lawns.

Teaching method

The second semester of AP Biology I have attempted to use a different method of material delivery (based on this Discovery Magazine article, and also the material in this earlier post). My attempt has been to lecture very little, provide the resources and materials so students can research their own information, and to provide rigorous and relevant assignments so students can investigate the content. I have tried to make myself available to answer questions in class while students are working.

Now it's your turn to teach me. What were the positives of this approach?
What were the negatives of this approach?
How would you improve the assignments?
Have you done your part in preparing for class?
Would this be a method in which you would like this class to continue?

I truly appreciate your comments on this, if you would like to keep them anonymous I certainly understand it as I hope you'll be free in pointing out where I can improve. I hope that as you comment you will also look at the other comments your classmates have added and reflect upon them (even disagree if you must) and add that information as well.

This one hits close to home!

National Geographic has an article entitled "Raiding the Bread Basket". It's about how agriculture has affected the Mississippi River Basin.

You wake up to cereal made from midwestern corn. You slip on cotton clothes, get into a vehicle fueled partly by ethanol and dine later on chicken and rice—all made possible by crops from the Mississippi River Basin, a vast area that stretches from Montana to New York and drains all or parts of 31 states.

All told, it's among the most productive farming regions in the world. Trouble is, fertilizer that flows from fields (and cities) takes a toll on local waters and eventually reaches the Mississippi River and the economically important fisheries of the Gulf of Mexico...

Read it and tell me what you think, especially about their ideas for change.

Make sure you identify the crop rotation strategies we covered in 1st semester!

When is an identical twin, not identical?

Epigenetics is an expansion of the classic Mendelian genetics. I have taught that identical twins have the same DNA, and they do, but it doesn't always express itself in the same way. This article is a good beginning to the idea of epigenetics. Scientists have researched...

a series of experiments that caused nematodes raised under the same environmental conditions to experience dramatically different lifespans. Some individuals were exceptionally long-lived, and their descendants, through three generations, also enjoyed long lives. Clearly, the longevity advantage was inherited. And yet, the worms, both short- and long-lived, were genetically identical.

Science News says... longevity may be because they inherited epigenetic marks — chemical tags on their DNA or DNA-associated proteins called histones — that change gene activity without changing the genes themselves.

This animation does an excellent job of showing what epigenetics is and how it affects genes.

Comments can be quite varied on this one. Explain how epigenetics might be used in medicine, agriculture, pharmaceutical, or other industries. Are there any drawback to learning more about this? How does this affect our knowledge of genetics? 

Antiobiotics - less use on farms?

This article in Scientific American goes along with the series of links I blogged about earlier about antibiotic resistance and what is being done to combat this medical issue. It seems that the FDA is limiting the usage of antibiotics that can be used on farms.

In industrial farming, antimicrobials are commonly given to farm animals to treat infections, and prophylactically to prevent disease or spur growth. But there is growing concern that excessive use on farms is helping to breed antibiotic-resistant microbes, from Salmonella  to Escherichia coli, which are harder to treat when they infect people.

The new rules, to come into effect on April 5, restrict veterinary surgeons to using the two cephalosporin drugs specifically approved for food-producing animals -- ceftiofur and cephapirin -- and ban prophylactic use.

What do you think of this new policy? Is this going to be a positive for human health or will it cause more problems? What issues could this pose to the farms that use antibiotics on a regular basis?

Zombie parasites in honeybees? Link to CCD?

In a previous post I referenced Colony Collapse Disorder, or CCD, an unexplained phenomenon in which bees are leaving their hives and dying in great numbers. It has had a tremendous affect on the honeybee population of the United States.

One hypothesis backed up by some newly published research documents that there are parasitic flies that are using honeybees as their host. As the Discover magazine article states...

Andrew Core from San Francisco State University has a possible answer, and a new suspect for CCD. He has shown that a parasitic fly, usually known for attacking bumblebees, also targets honeybees. The fly, Apocephalus borealis, lays up to a dozen eggs in bee workers. Its grubs eventually eat the bees from the inside-out. And the infected workers, for whatever reason, abandon their hives to die.

These parasites have been referred to as "Zombie" fly parasites because they affect the behavior of the bees. The picture below taken from both articles linked shows a larval stage emerging from neck of the honeybee.

 

As you comment determine what affect this could have on the ecosystems in which bees have a niche. Also comment upon whether the data actually shows a connection to these parasites and CCD, or if they are merely happening to the same organisms