BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: environment

A View into Life Millions of Years Ago

In an obscure geological valley at the very northern tip of Greenland’s large ice sheet, investigators have uncovered scientifically derived evidence of the existence of a lush, ancient ecosystem that was functioning over 2 million years ago. The clues to this ecosystem come from the oldest DNA ever recovered, bits and pieces of genetic material, carefully and tediously extracted from buried sediments representing more than 100 kinds of animals and plants. The investigators painstakingly extracted and “sequenced” the DNA strands and compared them to libraries of existing DNA “reads” from living species today.

DNA double helix horizontal
This is an incredibly impressive example of the power of environmental DNA (eDNA), as it is genetic material collected from the ambient environment and not individual organisms. The investigative team aimed to collect hundreds of samples from different locations within the ancient valley and reconstruct what this ecosystem looked like before the ice age. They found many different types of conifers, including poplars, thujas, and species like black geese and horseshoe crabs, that are now common further south of Greenland, but most of which are no longer found in the Arctic at all.
There are many reasons that I believe this discovery is important, not the least of which is that it may give scientists clues as to how some species were able to adapt to climate change in the past and give us some insight into climate change and evolution as we advance. It may also turn the time-honored discipline of paleontology on its head by driving it from its almost all fieldwork mode into the molecular biology laboratory.

The DNA/RNA biochemical process plays a very important role within the nucleus of each cell which defines the existence and evolutionary success of living plants and animals on the planet. The article which I selected from “Nature” discussed above, really emphasizes importance of these chemical structures regardless of whether we are investigating the past, looking into possible future biological scenarios, or looking to “improve”, correct or modify existing biological systems. Understanding both the future and historic past of the biology of the planet is no longer simply relegated to the desktop microscope, but more appropriately is a function of understanding the complex biochemical reactions at the molecular level, not just the cellular level. The extraction of biological (environmental DNA) material from historic sediments thousands of years old underscores the important changes taking place in this exciting new field and emphasized to me that the study of DNA/RNA biochemistry is very relevant to understanding all living systems, past, present and likely into the future.

 

How Could the Coronavirus Pandemic Harm the Environment?

In light of the chaos of the coronavirus pandemic, the worldwide pandemic caused by SARS-CoV-2, and all of its negative effects, people have been searching for some silver lining to the whole mess. I am someone who is passionate about saving the environment, and I was thrilled to hear about positive environmental outcomes that the pandemic caused. Unfortunately, while rumors have circled around that the environment has benefitted from quarantine, experts are now saying the opposite could soon be true. It is hard to tell what the future will hold, but signs point to a risk of a future with more traffic, pollution, and resulting climate change. 

During April, the prime of stay-at-home orders and when most people were on full lockdown, daily global carbon emissions were down 17% from 2019. However, by June they were only down about 5% from 2019, and at this point many people were still not going about daily life like “normal.” Corinne Le Quéré, professor of climate change at the University of East Anglia in Britain says that “as soon as the restrictions are released, we go right back to where we were.” A somewhat similar situation during the 2007-2008 financial crisis provides some insight into the future. At the time, emissions dropped, but later rose right back up. 

China exhibits an example of a quickly diminished hope of change in their air quality. As they were the first country to shut down, they had a dramatic shift in air quality due to slowed manufacturing and transportation. However, they were also one of the first countries to begin reopening, and this change did not last long. Factories pushed to make up for lost time and the pollution consequently returned, even growing to higher levels than before the pandemic in certain places. Traffic levels have also apparently bounced back to the same magnitude as before the pandemic, despite the fact that there are still people who have not yet returned to regular life and are unaccounted for in this statistic. Furthermore, industries in fossil fuels, plastics, airlines, automobiles, etc. have been negatively impacted by the virus and now are searching for any way they can to make a profit. Governments including the US have complied with their pleas for cash, regulatory rollbacks, and other “special favors.” As a result, “there’s a serious risk that polluters could emerge from this crisis bolder and potentially more profitable than ever,” says Lukas Ross, a senior policy analyst at Friends of the Earth. 

Another devastating example of negative environmental impacts can be seen in Brazil’s Amazon rainforest. During the pandemic illegal loggers, people who harvest, transport, process, buy, or sell timber in violation of national or subnational laws, took advantage of the “smokescreen” provided by the pandemic and caused destruction in the rainforest that surpassed amounts in previous years. According to satellite data, 64% more land was cleared in April 2020 than in April 2019, despite 2019 being a record year for deforestation for the past decade. This is significant because the Amazon rainforest plays a vital role in regulating the world’s oxygen and carbon cycles, producing roughly six percent of the world’s oxygen. As we know from biology class, oxygen is essential as it is one of the main building blocks of life. Our cells need oxygen to produce various proteins, and ultimately more cells. Oxygen is also crucial in many of our body systems. Without oxygen, the creation of carbohydrates, nucleic acids, and lipids would be impossible. The Amazon, which produces a significant amount of oxygen, is being destroyed more and more every year. The rainforest is also considered a carbon sink, meaning it absorbs large amounts of carbon dioxide from the atmosphere, lowering CO2 concentrations. Its function as a carbon sink helps combat CO2 levels in the atmosphere and climate change.

It is unknown what else is in store for the environment in the remainder of the pandemic and in coming years, but we can only hope for the best.

Can you get a disease from being outside?

The Alzheimer’s diseases and several genetic defects have been identified to connect with early onset family genetics. In this study chemists, toxicologists, and biologists have researched the environmental effects connected with health issues. The researchers examined the point that the human race would have all gone extinct if our bodies didn’t have the ability to metabolize, absorb, or excrete trace substances. In 2005, there was a lot of talk about the “exposome” causing many diseases. This research topic is very  interesting because it explains that everything you are exposed to can cause cancer. The fact that our exposome is everything we contact in our lives is concerning. Average light, invisible car exhaust and ambient street noise are all linked to birth defects. And now Alzheimer’s has been statistically linked to the environment.

Although Alzheimer’s is generally linked with age, researchers also believe it is linked to living in cities and poorer neighborhoods. According to new research unveiled at a recent global gathering of Alzheimer’s experts in London, stressful life events, poverty and racial inequities contribute to dementia risk in late life. A Study at the University of Wisconsin looked at levels of socioeconomic disadvantages such as poverty, education, housing, and employment to determine whether there was a stronger link to developing Alzheimer’s than by chance alone. They found that people in poor neighborhoods had worse cognitive performances in all aspects, which is linked to the fact that they had disproportionately higher levels of the Alzheimers disease biomarker in their spinal fluid. This could be considered an example of the effects that their exposome pose on their health. For example, in poorer neighborhoods, they have less access to healthy foods, safe exercisee options and healthy environments. This unhealthy environment leads to increased risk of diabetes,  cancer, and early death.

Does Exposure to Toxins In the Environment Affect One’s Offspring’s Immune System?

A study has recently surfaced stating that maternal exposure to industrial pollution may harm the immune system of one’s offspring and that this impairment is then passed from generation to generation, resulting in weak body defenses against viruses.

Paige Lawrence, Ph.D., with the University of Rochester Medical Center’s Department of Environmental Medicine, led the study and conducted research in mice, which have similar immune system functions as humans. Previously, studies have shown that exposure to toxins in the environment can have effects on the respiratory, reproductive, and nervous system function among generations; however, Lawrence’s research is the first study to declare that the immune system is also impacted.

“The old adage ‘you are what you eat’ is a touchstone for many aspects of human health,” said Lawrence. “But in terms of the body’s ability to fights off infections, this study suggests that, to a certain extent, you may also be what your great-grandmother ate.”

“When you are infected or receive a flu vaccine, the immune system ramps up production of specific kinds of white blood cells in response,” said Lawrence. “The larger the response, the larger the army of white blood cells, enhancing the ability of the body to successfully fight off an infection. Having a smaller size army — which we see across multiple generations of mice in this study — means that you’re at risk for not fighting the infection as effectively.”

In the study, researchers exposed pregnant mice to environmentally relevant levels of a chemical called dioxin, which is a common by-product of industrial production and wast incineration, and is also found in some consumer products. These chemicals eventually are consumed by humans as a result of them getting into the food system, mainly found in animal-based food products.

The scientists found the production and function of the mice’s white blood cells was impaired after being infected with the influenza A virus. Researchers observed the immune response in the offspring of the mice whose mothers were exposed to dioxin. Additionally, the immune response was also found in the following generations, as fas as the great-grandchildren (or great- grandmice). It was also found that this immune response was greater in female mice.  This discovery now allows researchers to have more information and evidence to be able to more accurately create a claim about this theory.

As a result of the study, researchers were able to state that the exposure to dioxin alters the transcription of genetic instructions. According to the researchers, the environmental exposure to pollutants does not trigger a genetic mutation. Instead, ones cellular machinery is changed and the immune response is passed down generation to generation. This discovery explains information that was originally unexplainable. It is obviously difficult to just avoid how much toxins you are exposed to in the environment, but it is definitely interesting to see the extent of the immune responses in subsequent generations. We can only hope that this new information, and further discoveries, help people adjust what they release into this world that results in these harmful toxins humans are exposed to, and their offsprings.

 

 

 

Did You Know Plants Can Talk?

 

For thousands of years language has been a crucial part of cultures around the world, and a method unique to humanity of transmitting ideas, thoughts, emotions between us. Language has allowed us to work harmoniously together for our mutual improvement and survival. Recently, however, two researchers, Dr. Kim Valenta and her colleague Omar Nevo, have discovered that plants too, have developed their own unique and intricate method of conveying information to their pollinators; “the easier it is for fruit eaters to identify ripe fruits, the better the chance for both [, the plant and the fruit,] to survive.

The most vivid example of plant communication can be found in Madagascar’s Ranomafana National Park and Uganda’s Kiabale National Park where berry plants have evolved “to match each animal’s sensory capacities, [thus] signal[ing] dinner time in the jungle…” Dr. Valenta and Nevo analyzed the exact colors of each fruit with a spectrometer, and “with a model based on the visual capacities of the seed-dispersing animals, they also determined who was most likely to detect different fruit colors contrasting against an assortment of backgrounds.” The researchers concluded that “the colors of each fruit were optimized against their natural backdrops to meet the demands of the visual systems of their primary seed dispersers,” i.e. pollinators. Thus, red-green color-blind lemurs, in Madagascar were best able to detect the fruit with a blue yellow color scheme and monkeys and apes in Uganda, with tricolor vision like humans, were clearly able to distinguish red berries against a green backdrop.

Also recently discovered was that plants can communicate to their pollinators through scent. Dr. Nevo performed a scent-based study on the lemurs in Madagascar. His team collected various ripe and unripe fruits from all over the jungle of Ranomafana. “He suspected the leumur-eaten fruits would have a greater difference in odor after they ripened than the bird-eaten fruits.” To discover exactly how this scent-based communication worked, Nevo used the “semi-static headspace technique.” From this experiment it was confirmed that “fruits dispersed solely by lemurs produced more chemicals and a greater assortment of compounds upon ripening. It is now known that wild lemurs actually spend quite a lot of time smelling for the vivid difference in odor between ripe and unripe fruits in the jungle.

It is astonishing how plants have evolved over the years to be able to communicate with their pollinators for the betterment and expansion of their species. I would be interested to find out, what other organisms communicate (single cellular, multi-cellular, etc.) and what kind of information they find necessary to convey to others for their survival?

 

 

 

 

Saving our planet, one fart at a time

Cows are really cute. They just stand there in the grass, four-legged and everything, eating their grass, mooing, and just living life like cows should. They taste good, and they make milk, which means that we (humans, if you needed that clarification) love to farm them. As a result, there’s a LOT of them (more than 1.5 billion) all over the planet. Seems like a good thing right? I mean, how could too much of this be a bad thing?

Look at this cutie just chillin’. Photo by Daniel Schwen.

Unfortunately, cows have a dark side. Cattle are a type of animal called a ruminant, which have specialized stomach to digest plant material by storing it and fermenting it. Once fermented, the food, known as cud, must be chewed again before digestion is complete. In the cow’s stomach aiding it in this process are tiny microbes known as methanogens. These guys allow cows to digest things like cellulose (plant matter), but produce methane as a waste products. Cows then either burp or fart out this gas.

With all the cows on the planet, the methane being emitted has become a major problem. Methane is a greenhouse gas 25 times more powerful than carbon dioxide, meaning it warms the planet at a much higher rate. Livestock account for 14.5% of all anthropomorphic (human) greenhouse gas emissions, and cattle account for 65% of all livestock emissions. So obviously, cows’ farts and burps are a problem. So how can we fix it?

Our cute friends are a large part of this… Made by Al Rodger.

The three issues, according to microbiologist Lorenzo Morelli, are diet, genetics, and the microbiology of cows. Phil Garnsworthy of Ruminomics, an organization with a goal of reducing cows’ emissions, looks to selection to help lessen the problem. According to him, cattle vary by a factor of two to three on the amount of methane given off. By simply favoring and only breeding those cattle that only emit low amounts of methane, the problem can be immediately mitigated. Dairy Farmers have an extra incentive to reduce methane by breeding low methane cows separate from the environment, as well. The methane represents lost energy that could go into producing more milk, and so adding low-methane to a list of attractive cow characteristics would not only help the environment, but also farmers’ wallets. But plain ol’ artificial selection isn’t the only option.

Changing cows’ diet may also help reduce the problem. Scientists at Aarhus University are looking into producing a genetically-engineered grass to give to cows. By changing and running tests on the DNA of the grass and eventually finding the optimal type, the scientists hope to make grass less stiff and easier to digest for the cows, which would not only decrease methane production due to less activity from the microbes, but also increase milk production.

Cows grazing. Photo by Scott Bauer.

There is an also an option of dealing directly with the microbes themselves and their methane release. For example, Researches at Penn State are studying the effects of  3-nitrooxypropanol (3NOP) on cows’ methane emissions. 3NOP, when put into cow feed, would in theory stop the microbes from producing methane when it binds to the cows’ digestive tracts. Cattle saw a 30% reduction of methane when fed 3NOP.

And finally, there is always the prospect of genetically modifying cows themselves to produce less methane. The tricky part about this is that it’s the microbes that actually produce the methane, not the cows. Morelli says, “We think that animal genetics may well influence their gut microbiology. However, this link has not been proved and we are still in the data collection phase.” Essentially, though we might be far from a GMO cow that produces less methane, it is not outside the realm of possibility. Even now, the Genome Canada project is looking into the genes responsible for lower methane emissions, with the hope of spreading the gene to other populations of cows.

Personally, I believe scientists should be doing whatever they can to reduce methane emissions. This is our planet, and we need to do everything we can to save it. This includes GMO research, which I realize makes some people uneasy, but in my opinion is a great, new way to help our planet and help ourselves. However, any solution that would hurt cows, reduce lifespan, or ruin milk or beef taste should only be used as a last resort. Even then, I would be hesitant to implement such changes. Essentially, what route is the most efficient and practical, and what are you willing to sacrifice? These are the two questions that must be answered in finding a way to reducing cows’ methane emissions.

All in all, it seems cows are on their way to being lesser burdens on our environment. And that’s a great thing, because then I would be able to appreciate their cuteness more without feeling a bit of guilt.

 

 

The Buzzing Battle of the Bees

Bee

http://commons.wikimedia.org/wiki/File:Bees_on_sunflower.JPG

 

There is a species of bees called “commercial” bees. These bees are kept by beekeepers to pollinate crops such as tomatoes, sweet peppers, and oilseed. This population of managed bees is coming down with “fast evolving viruses”, according to the University of Exeter in Science Daily News.

Then there are “wild” bees, free to fly around, not employed by beekeepers. The viruses that the commercial bees have are starting to spread to the wild bee population. Currently, researchers are “calling for new measures” to protect the wild pollinators, and confine the commercial, diseased population. In the article, Dr. Lena Wilfert said this can be controlled by beekeepers keeping a vigil eye and monitoring the commercial bees they own. It is their “responsibility” to do so. Also, interesingly enough, the international transport of these commercial bees must have more checks and security. They must be screened better, in order to get a better sense of how many have a disease, so they know not to set any of the commercial bees free into the wild.

The major cause of the spread is the Varroa mite. This spreads viruses, such as the Deformed Wing Virus, and may increase the power of the viral spread. It significantly weakens bees, causing their RNA to deteriorate. The article says that it has been “identified as an emerging disease in pollinators,” and there is a connection between wild bumblebees who have it, and commercial honeybees.

The poor management of the commercial bee community is the cause of this horrible break out of diseases among innocent wild bees. In the future, researchers plan to investigate which species of commercial bees are the major cause of the breakout and spread. The wild bee population is extremely important for our environment, and beekeepers need to realize that, and make sure their bee farm does not spread disastrous diseases.

 

*Additional information is found through the last two hyperlinks.*

*Original article is the first hyperlink.*

The Moral Roots of Trees

By Richard Sniezko

By Richard Sniezko

Recently in Southern Utah it has come to the attention of many ecologists that the tree species, whitebark pines, is on the cusp of becoming an endangered species due to climate changes and droughts in the south. As a quick solution, some members of the scientific community have suggested “assisted migration” whereas humans would restore the whitebark pine population by dispersing its seeds from areas of the hot south to more adaptable, cooler weather up north.

To put this proposition to the test, graduate student, Sierra McLane, under Dr. Sally Aitken of the University of British Columbia, conducted a study and spread the seeds of whitebark pines throughout much cooler and consistent weather of the British Columbian mountain ranges. As a result, 20% of the seeds germinated and continue to grow here, allowing McLane to affirm that whitebark pines would successfully grow in the colder climate.

Despite her evidence, McLane, along with many other scientists’ “assisted migration” is bound more by an ethical dilemma than biological. Although it is clear that these whitebark pines are a crucial species to provide animals, like bears and birds, with food and shelter, some scientists are skeptical over how easily these animals will be able to adapt to the change in their location and others are morally conflicted over whether humans should interfere with nature thus changing the future. While assisted migration continues be deliberated by scientists as a possible solution to the threatened whitebark pine tree population, what is your attitude on the subject? Do you believe it is our moral responsibility to “take care” of the environment or should we not interfere with the natural selection of wildlife?

Original article: http://www.nytimes.com/2014/09/23/science/under-theat-flight-may-be-best-response-for-trees.html?ref=science&_r=0

 

Another reason to not cut down old trees

Imagine if human growth accelerates, instead of slowing down after adolescence. This way, humans would weigh less than half as much at their middle age than at when they are at their old age.

In a study published in the journal Nature, scientists found out that the growth of the tree accelerates with the tree size. This means that the bigger the tree, the faster it will grow to become even larger.

This discovery is important, as it tells us another reason to save old trees to help protect our planet. The bigger the tree size, the higher the rate of carbon accumulation of the tree. Therefore, one old tree helps lessen the greenhouse gases in our atmosphere much more than a tree that is much younger. Bigger and older trees are important carbon sinks to our environment.

Photo by Author

Photo by Author

Here is a link to a video which showcases a giant tree — the extreme end of the spectrum.

Original article: http://dotearth.blogs.nytimes.com/2014/01/15/if-old-humans-grew-like-old-trees-stand-back/?ref=biologyandbiochemistry

Learning to kill trees in order to save them

According to a recent New York Times article, there are researchers who are trying to figure out why trees seem to be dying for no reason. The problem they focus on is called the “sudden aspen decline” which is where aspens begin to die in large numbers after a period of drought. The scientists wanted to delve further into the plants to see what exactly was happening to the plants. The two theories were that either the tree would close its stomata to prevent transpiration but also cut off its carbon dioxide supply or that the xylem was collapsing from not having enough water. In the end they decided that in the case of the aspens the xylem had been damaged in the samples they collected from the dead trees but there could have also been other factors such as bugs damaging the trees when they were weakened by the drought. The exact details of the research were presented in a paper by William R. L. Anderegg. This research will help the scientists find ways to prevent these massive deaths of forests but this is not the only reason or the major reason for forest death so a lot of research is still needed to really help these ecosystems. The author of the Times article had also previously published a much longer article on forest deaths which goes into climate issues.

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