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May 8, 2012

Posted by srstone in Biology, Evolution, Genetics, Health, Medicine, Science Education.
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Viruses: Friend or Foe?

What is invisible to the naked eye, can affect the Earth’s climate, has a tiny shell, and can causes cancer?  Viruses are considered non-living, but play a major role in our bodies and environment.  In fact, viruses kill half of the bacteria in the ocean every day.  To get an idea of how much bacteria that is, a teaspoon of water contains approximately a billion bacteria.  Recent estimates show there are 1031 viruses on this earth.  That reads, 10 billion trillion, trillion.  Although viruses are smaller than what the unaided eye is capable of viewing, if all viruses were stacked end to end, they would be lined up for about 100 million light years.

How Viruses Work

 

Viruses are constantly on the attack from the outside of our body desperately trying to get in, but 4 trillion viruses also reside inside our body.  While some viruses are trying to find a host cell and cause harm, many viruses are necessary for a healthy life.  Some of the viruses inside of us can protect us from detrimental bacteria, but can also help balance the population of bacteria vital to our health.  A similar phenomenon occurs in the ocean.  Without viruses consuming half of the bacteria day in and day out, the levels of bacteria in the ecosystem could hamper the living of certain species.  Also, bacteria contain carbon and lots of nutrients.  With the viruses consuming the bacteria, there is a constant recycling throughout the ocean.  There is a hypothesis that because of all the carbon that’s coming out, it could be affecting the Earth’s climate.  Any of the carbon that is sent back to the atmosphere is going to trap heat (greenhouse effect).  It may be an extreme thought, but these tiny, non-living viruses are partially responsible for the weather.

Bacteriophages: the lifeless killers

Viruses that attack and dispose of bacteria are known as bacteriophagesFelix d’Herelle discovered the extraordinary conclusion that viruses can kill bacteria through treating a dish of bacteria with fluid from patients with dysentery!  He actually began a business selling viruses that could cure bacterial infections.  Hypothetically, there are viruses that exist in nature that can kill the most severe bacterial infections, but it’s a matter of discovering the right viruses.  Each species of bacteria has a series of bacteriophages that can eliminate it.

Antibiotics and Viruses: An evolutionary arms race

Before antibiotics were discovered in the 1930s, a method called phage therapywas used to combat infections.  However, once these antibiotic “magic pills” were discovered, phage therapy stood in the distance.  The chemicals were reliable and scientists knew how to make them.  However, with the current widening spread of antibiotic resistance caused by bacteria developing resistance to modern medicine’s most well-used antibiotics, it’s beginning to look like phage therapy wouldn’t be a terrible idea.  One main argument phage therapy new found interest: antibiotics can’t evolve, while viruses can.  Scientists have reached the point where viruses can be engineered and genes can be strategically placed to enhance their effectiveness.  This genetic and evolutionary tinkering could allow scientists to develop viruses to strategically kill various bacteria that might be antibiotic resistant.

Genetic Engineering of Viruses

 

Viruses: Directors of Their Own Fate?

In the wake of the recent deadly avian flu virus, critics have questioned whether the spreading from mammal to mammal could have occurred on its own.  A study completed at MSU by Justin Meyer was started with the thought that it would be a wild goose chase.  Meyer wondered if lambda phages could evolve another way a new way to enter its host.

lambda was used to infect the gut bacterium E. coli.  It is harmless to humans.  The most common means for lambda to get into a cell is by attaching to its outer membrane.  The genes and proteins contained by the lambda are then injected into the microbe.  Meyer used E. coli that didn’t make the molecules necessary for the virus to grab onto.  This meant that the only viruses that would survive were ones that mutated to use a different surface molecule.  Shockingly, within 15 days, Meyer’s experiment showed that viruses were using a new channel in E. coli known as OmpF.

Meyer re-conducted the experiment with 96 lines of the virus and E. coli.  Of those 96, 24 of the lines began to use OmpF as the pathway into the host.  Because of the repeating phenomenon, the genomes of the evolved viruses were sequenced, finding that four mutations were required for the viruses to thrive.  All four were required, not a single one, or even three out of the four.  Meyer estimated the chance of all four mutations arising at once was nearly impossible: one in a thousand, trillion, trillion. However, the lambda viruses evolved to contain all four mutations in a couple weeks on a regular basis.

As incredible as this experiment is, it is somewhat frightening.  Meyer showed how easily viruses can evolve completely new traits, which can lead to new diseases.  This is exactly the reason why when treating a sickness with antibiotics, the patient MUST finish taking the dosage until it is gone, otherwise the virus can come back even stronger.

 

 

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 Something in the Water: Tracing the Cholera Outbreak in Haiti April 13, 2012

Posted by srstone in Biology, Environment/Conservation, Evolution, Genetics, Health, Medicine, Policy, Science & Culture.
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 Something in the Water

Cholera Under the Microscope

When we go to the sink to get a glass of water from the sink, we trust that what the water is comprised of is safe for us to drink.  Most of us don’t give a thought as to what could be in it.  This is one of the luxuries of living in a first world country.  However, those in third world countries, such as Haiti, are not so fortunate.  Shortly after the earthquake in Haiti in 2010, a cholera outbreak occurred.  When an outbreak like this occurs, the goal is to not only check the spread of the disease among Haitians, but to prevent the bacteria from swapping DNA with other cholera strains in the country to form a more dangerous bug much harder to treat.

Antibiotic-resistant Cholera: Mechanisms explored

Bacteria reproduce asexually by a process called binary fission.  Binary fission causes two genetically identical bacterial cells to be produced.  If this was the only method bacteria had to procreate, treating a disease with antibiotics would be simple.  Antibiotics aim to either kill bacteria directly or hamper their ability to grow and reproduce.  This can be done by crippling the production of the bacterial cell wall and inhibiting protein, DNA, or RNA synthesis. 

However, when we put our bodies on the attack with the use of antibiotics, bacteria respond by playing their side with different defensive mechanisms.  Some of these mechanisms include changing the permeability of their membranes.  For example, bacteria can decrease the number of channels available for the antibiotics to enter the cell.  Another mechanism works by changing the actual physical structure of the antibiotic once it enters the cell so that the drugs can’t bind the way they were designed to in order to have an effect.  Although both of these mechanisms prevent antibiotics from carrying out their job, bacterial recombination is the most common form of developing antibacterial resistance.  When this happens, bacteria gain genetic variation by swapping DNA with other bacteria.  This allows the bacteria to acquire resistance to the drug.  A plasmid, which is a circular piece of DNA, can encode resistance to multiple antibiotics. Thus if one bacterial cell in the environment has evolved resistance to an antibiotic, it can easily share that information with other surrounding bacteria leading to an epidemic of widespread antibacterial resistance.   A transposon, known as a “jumping gene”, can jump ship from DNA to DNA molecule.  The transposon then becomes part of the plasmid.

Where did it come from?

Cholera, which had never been seen before in Haiti prior to the earthquake, had the advantage.  Nations offering their help focused on the earthquake recovery while cholera entered Haiti under the radar.  Reducing the fatality rate from cholera has been a success; however the response was slow to fully develop.  The most likely story is that cholera spawned from a Nepalese volunteer at the Minustah base.  Understandably, no one wanted to take responsibility for bringing an epidemic to a country that already needed all the help they can get. 

To resolve the “blame-game”, Danish and American scientists collaborated to determine where the cholera came from.  Haiti’s cholera strain and Nepal’s cholera strain of the bacteria were examined using the most comprehensive type of analysis: whole-genome sequence typing.  Virtually identical, the Nepalese were forced to accept blame.  Another method, pulse-field gel electrophoresis was also used as evidence.  Scientists found that cholera erupted in Nepal in July 2010, but was under control the following month in August.  Unfortunately, this was the same month that Nepalese soldiers left for a recovery mission in Haiti.        

Resolutions?

Through the application of genetics, the cholera strain has been identified.  Unfortunately, this doesn’t solve Haiti’s problems.  Only 12% of the population has access to piped, treated water.  The rest find their water in rivers and wells.  These are the same rivers that contain feces and that Haitians wash their clothes in.  Vaccinations and supportive care will aid in the conquering of cholera, but until safe water is more readily accessible, the country needs to be prepared for round two.

A Typical Haitian Laundry Room

Effect of environmental toxins on GATC methylation in E. coli May 3, 2011

Posted by ljsteele in Biology, Chemistry, Ecology, Environment/Conservation, Evolution, Genetics, Health, Marian University curriculum, Physiology.
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With the end of the semester drawing near it is becoming that time again when the results are piling in from research you have been working on all semester. As we speak, the final data collection and analysis is taking place in biochemistry, a team of student researchers are exploring of environmental toxins of DNA methylation  in the bacterium E. coli. 

The Bacterial Genome

Bacteria exist throughout the world and can survive in almost any climate . Bacteria are unicellular and can consist in a wide range of environments such as a pond all the way to soil.  One unique attribute of the bacterial genome is that it contains adenine methylation , opposed to mammalian organisms which contain cytosine methylation at GpC islands.  Adenine methylation is when a methyl group becomes attached to the adenine nucleotide on the DNA. When a methyl group is donated from SAM to form a covalent attachment, it is made on the adenine which can cause steric hindrance of transcription factors and differential effects of DNA binding proteins, which can contribute to a change in gene expression.  In previous studies  it has been shown when E. coli is exposed to different carbon sources (ie glycerol or glucose).  Some areas of the genome become demethylated.  In the bacteria E. coli almost every adenine (A) in the GATC sequence is methylated.  To block the methyation at the GATC sequence, a protein must be present to inhibit the DAM methyltransferase from depositing a methyl group on the adenine.

What does Methylation do?

Adenine methylation has many roles in bacteria. Methylation can effect gene expression, cell cycle, virulence, and how proteins interact with the DNA. For the research we are performing, we are concerned with what effect the environment has on changing adenine methylation on the GATC repeats. There are about 20,000 GATC repeats in the E. coli genome and under normal log growth conditions almost every single repeat is methylated. It has been found that when bacterial cells are in a log growth phase there are 6-10 sites which are not methylated. These nonmethylated sites lie up and down stream of promoters of different genes. The lack of methylation may allow DNA binding proteins to modulate their function to allow a functional change in gene expression.

Pollutants and the Genome

In the study we are performing we wanted to see how three classes of chemicals pollutants commonly found in the Midwest affect adenine methylation at the GATC site. We choose three pollutants to represent chemicals that fit into the families of common water pollutants, which are heavy metals, chlorinated compounds and nitrogen rich compounds.Gel Electrophoresis

The above families of compounds will be compared to samples collected from different areas around the campus of Marian University, Indianapolis, IN. Supplements will be added to all the samples to generate a rich liquid media that will facilitate bacterial growth.  With 6 different test groups and 2 controls we are going to seek to determine if any of our known compounds or a compound present in our environmental sample has an effect on the methylation.  The determination of methylation can be done by using restriction enzyme digest with endonuclease selecting specifically for the nonmethylated site.  The enzyme we have chosen was MBO and AVI.  When all the genomic DNA from the bacteria is extracted and digested, then it will be ran on a gel to be imaged to determine if the bands of digested DNA differ depending on the chemicals present during growth.  This is a time efficient way to examine if any changes in methylation levels have occurred.

What Does It All Mean?

For conclusion, the relevance of this study includes a few things.  This study will provide evidence to show if environmental toxins have an effect on bacterial DAM methylation. One role bacteria play in an ecosystem is influencing the flow of nutrients which support plant and algae growth. The results of our proposed study may display that toxins have an effect on methylation patterns which could lead to an increase the mutation rate of the bacteria genome itself.   Destructive mutations may decrease bacterial populations leading to a disruption in the ecosystems nutrient flow, hence disruptions in plant and algae growth with effect additional aquatic and terrestrial organisms.

Penguins, endangered? May 3, 2010

Posted by Kyle in Behavior, Biology, Climate Change, Ecology, Environment/Conservation, Evolution, Fun.
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"I believe I can fly!"

Cape penguins (Spheniscus demersusare) are an endangered species of penguins off the coast of South Africa. Between 2001 and 2009 there was a 60% decline in population numbers of Cape penguins. Researchers believe that the decline in Cape penguins is partly due to the lack of food as a result of overfishing.  Without food, the penguins obviously can’t survive.  A study done by researchers in South Africa has shown that by managing commercial fishing, they may be able to restore population numbers in penguins.

After doing a little more research, I discovered an easier solution to the problem. The penguins could just fly away (similar to polar bears rapidly evolving), and using a strategy similar to what was done in the movie Fly Away Home, the penguins could be saved. While it may seem slightly unrealistic, just watch the video below and all doubt will be removed. It seems that penguins learning to fly isn’t that crazy of an idea. (The video is obviously not real, and I am not serious.)

Lazy Birds May 3, 2010

Posted by Kyle in Behavior, Biology, Ecology, Evolution.
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Being a bird can be extremely difficult, especially when it comes to raising offspring.  The best way to pass on your genes, and at the same time spend no energy in doing so, is to let another bird do the work!

Brood Parasites

brood parasite young outcompete their host "siblings"

Brood parasites get around the huge investment of raising offspring by tricking another bird into doing it.  Brood parasitism is not a very common reproductive strategy across species (although rates of brood parasitism are high), but it definitely has its benefits.  The less time a bird is spending incubating eggs, the more time that individual can spend on foraging or mating.  The handful of species that use this strategy to gain an edge are constantly trying to trick the host birds, while the host birds are always on the lookout for parasitic eggs. This has led to an evolutionary arms race, with both sides working hard to win.

The costs of being fooled by brood parasites are huge. Not only does the fooled bird have to spend time raising someone else’s offspring, usually it’s not even the same species of offspring.  There is no genetic benefit in raising someone else’s young.  There is also the possibility that the parasitic chick out-competes the host’s chicks. This is the case with the Cuckoo Finch (Anomalospiza imberbis) and the Tawny-flanked Prinia (Prinia subflava). If the Cuckoo Finch egg is not discovered by the host, the Cuckoo Finch chick will hatch first and grow larger than the host’s chicks, out-competing its “siblings” for food and space until the host’s chicks eventually die. The cost associated with this relationship has led to a complicated defense system used by Prinias.

egg patterns of host and parasite are very similar

In a study done by Dr Claire Spottiswoode and Dr Martin Stevens of the University of Cambridge, the researchers worked on the two tropical African species to determine what strategies are used by both sides to win the battle. The back and forth struggle between the two species has resulted in Cuckoo eggs being almost identical to those of the Prinia. Researchers tested how Prinias detect impostures by taking eggs from Prinia nests and putting them in other Prinia nests. They then observed whether or not the eggs were rejected.  The results showed that the Prinia are extremely talented when it comes to distinguishing between their own eggs and those of another bird. By using color and pattern the host birds are able to distinguish among their eggs and those of the parasite birds. Although this sounds like a great plan, the reason it isn’t so popular is because it doesn’t really work that well. In another study researchers used Zebra Finches (Taeniopygia guttata) to look at brood parasitism, and found that only one-third of the eggs laid by brood parasites are actually reared.

How similiar are chimps and humans? April 30, 2010

Posted by Kyle in Behavior, Biology, Ecology, Evolution.
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Many researchers are interested in what makes chimps and humans different, as well as the similarities. A recent article on Science Daily highlighted two studies published in Current Biology on how chimpanzees deal with death.  The first study shows that chimps may have a more developed awareness of death than once thought.  Researchers observed how chimps responded to dying and dead chimps of their group.  In some cases, mothers would continue to carry and care for young that had died.  Researchers also observed how a group of chimpanzees responded to a dying female in the days leading up to her death.  They found that there were similarities between the chimps behavior towards the female and human behavior when an elderly relative is dying.

Chimp mother carrying mummified infant

Since chimps are our closest evolutionary relative, it makes sense that they would share some things in common with us.  In the second study researchers found that mothers would continue to care for their dead young, even months after the infant had died. As time went on, the mothers slowly began to separate from the corpses. These observations seem to indicate that there is a close bond between mother chimps and their young.  As Dora Biro of the University of Oxford points out, chimps resemble humans in many of their cognitive functions.  How chimps react to death and are affected by it could shed light on the evolutionary origins of human comprehension of death.

The similarities between humans and chimps starts with DNA.  Humans and chimps have very similar genomes. In fact, over 98% of a chimps DNA is the same as a humans, with most of the differences being in non coding regions. Another article on Science Daily addresses this similarity. According to Katherine Pollard, assistant professor at the UC Davis Genome Center and the Department of Statistics, the differences between humans and chimps is in how we use our proteins, not in the actual proteins.  Pollard and other researchers found “highly accelerated regions” of DNA when comparing the DNA of humans and chimps. These highly accelerated regions were areas of DNA that had evolved, however only a few of these regions contained genes coding for proteins. Researchers believe that one region may contain a gene important for brain development. As different as chimps and humans appear, there are more similarities than most people realize.

There are many researchers that have highlighted key similarities and differences in humans and chimps. With more research comes more interesting discoveries linking us to our evolutionary relatives. Some other interesting similarities have been pointed out recently, such as the understanding of fire as well as culture among different groups of chimps. More interesting articles on current research can be found on Science Daily.

Creationism vs. Evolution: How did we get here? April 30, 2010

Posted by Jill in Evolution, Genetics, History of Science, Science & Culture.
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Darwin's finches

I was in the library this week studying for finals and finishing up the rest of the work in my classes when I came across this book called Is God a Creationist, which contained many valid arguments for both scientific theory as well as theological explanations as to how life on this planet began. The age-old question of our existence has long been debated by both scientists and theologians.

Since Charles Darwin published his findings on the Galapagos finches and his theory about evolution, there has been an intense debate between scientists and theologians. Scientific evidence, such as carbon dating, dates the earth at about 4.54 billion years old, long before the existence of mankind. Theologians argue the biblical implications of the origins of the world saying that Earth was created by God and all living things were created by God. Literal interpretations of the Bible are difficult to comprehend for many reasons including the fact that the Bible was written 3,000 years ago so the interpretation and meaning of words could have been different than what they mean today and the fact that the Bible was not written as or intended to be a historical accurate account of the world because it is a book filled with symbolism.

The Bible contains two creation accounts in the book of Genesis. The first creation account can be found in Genesis 1-11. According to Michael D. Coogan, the first account of Genesis describes the “formation of the cosmos, an ordered universe, out of preexisting but chaotic matter—an unformed earth and unruly sea over which a wind from God swoops like a large bird” (Coogan 28)

The majority of evolutionary theorists believe that there was preexisting matter from which our universe has evolved. Besides the concepts of evolution, scientists are also known for having developed the “Big Bang Theory” to explain the origins of matter in a naturalistic framework, from which our universe was theoretically created. The Big Bang Theory is described as a moment 15 billion years ago when the total amount of matter in the universe exploded from a point and moved out to form the expanding universe today. The scientific perspective on the origins of the world can be described by: “the world had a beginning under conditions in which the known laws of physics are not valid, and as a product of forces or circumstances we cannot discover…the scientist’s pursuit of the past ends in the moment of creation” (Is God a Creationist 35)

Evolution and natural selection cannot be ignored even by theologians because there is significant scientific evidence that states that both do and have existed. At the very least, it is evident that at least artificial selection exists because of the domestication of animals such as horses, dogs, and cats. Humans were able to domesticate or breed certain characteristics of an animal, for example wolves that were friendlier to man than those that tried to attack, and cultivated these characteristics over thousands of years to produce the species we know as our four-legged friends, dogs.

Do chimps think and act like us because they are one of our closest ancestors?

Through molecular genetics, it is possible to find evolutionary pathways through the similarities in homology of DNA between different living species. Also, extracted DNA from fossilization records are the scientific equivalent of “paternity tests” of our earliest ancestors, determining how closely related we are genetically to other species, namely apes. Molecular geneticists as well as evolutionary theorists believe that chimpanzees and humans emerged from a common ancestor 6 million years ago, dating long before the creation of Adam and Eve (according to the Biblical timeline). The genetic evidence for humans being potential “cousins” of chimps is astounding in that approximately 99% of our DNA is identical to that of chimpanzees. The one percent variance between our DNA and that of chimpanzee DNA is what distinguishes us from apes, but in the genetic world one percent could potentially mean that all of the DNA in that one percent is what makes us distinctly different from say starfish. Although theologians refuse to believe that humans evolved from apes, how do we account for species such as the Geico Neanderthals or other upright-walking mammals that shared more behaviors with humans than chimpanzees do. Neanderthals looked more like humans today than modern apes do, so how does religion account for these differences?

An interesting view on the culmination of both the scientific and religious aspects concerning our existence can best be described by John MacArthur: “For the scientist who has lived by his faith in the power of reason, the story ends like a bad dream. He has scaled the mountains of ignorance; he is about to conquer the highest peak; as he pulls himself over the final rock, he is greeted by a band of theologians who have been sitting there for centuries.”

A Second “Lab Rat” has its Genome Mapped April 28, 2010

Posted by ecogeeko10 in Behavior, Biology, Evolution, Genetics, Health, Neuroscience, Physiology.
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Many behavioral ecologists, geneticists, physiologists, etc. are familiar with the zebra finch (Taeniopygia guttata). In fact, many have considered it to be the avian version of the white lab rat. Because of this, these researchers should be excited to hear that scientists have just recently decoded the zebra finch’s genome.

A genome to explore behavior

The zebra finch isn’t the only bird to have its genome mapped (the chicken was completed first) and it’s only about one-third the size of the human genome. However, this was a unique find because it will greatly help behavioral ecologists to understand the underlying mechanisms that help baby songbirds learn how to sing from their parents. This isn’t something that could have been done with the chicken genome because chickens don’t learn how to “cluck” from their parents—they just do it. Zebra finches, on the other hand, are similar to humans because human children also learn how to speak from their parents.

The zebra finch genome gives us the opportunity to explore the influence of genetics on language development.

Researchers are already analyzing the genome and they are finding that a good portion of the bird’s DNA is actively participating in the hearing and singing of songs. What’s more, these short simple songs are rooted in a great deal of genetic complexity. To date, it has been understood that the very act of singing and hearing songs activates large, complex gene networks in the bird’s brain. However, the current genomic research is revealing there to be many more participating genes than once thought. Right now it seems that there may be approximately 800 total genes that are active in this process!

Genes not acting as genes

New evidence is also showing that many of the activated genes aren’t acting like genes in the traditional sense. Rather than coding for proteins, the DNA from these genes is transcribed into short stretches of non-coding RNA that control the expression of other genes involved in the zebra finch’s vocal communication. Since non-coding RNAs are very influential in the developmental processes in animals and since they are thought to be instrumental in the evolution of higher organisms, the vocal learning that is found in the higher organisms may use non-coding RNAs as their driving force.

The evolution of language

It is also worth noting that when comparing the newly mapped zebra finch genome with the chicken genome, there seems to be some obvious differences that may point towards the evolutionary pathway that gave rise to birds that are capable of vocal learning. For instance, the evolution of the ion channel genes—which are important players in behavior and neurological function—in the zebra finch brain were greatly accelerated; the expression of the male sex chromosome genes seems to have been modified; and the production of new variants of neurobiologically important genes have taken place. It is amazing to see how much has learned in such a short period of time!

From birds to humans

It took the combined effort of more than 20 institutions to map out the genome of this song bird and now everyone has the opportunity to reap the benefits from this work. The newly gathered information should prove to be instrumental in helping us to better understand how humans learn language and perhaps it will help neuroscientists to identify the genetic and molecular causes of certain speech disorders that are associated with various illnesses such as Parkinson’s disease, strokeautism, etc. With the parrot genome scheduled to be completed by the end of this year, who knows what all we can learn about our little feathered friends and even ourselves!

Research Conferences are Cool! April 25, 2010

Posted by ecogeeko10 in Behavior, Biology, Ecology, Evolution, Genetics, Neuroscience, Physiology.
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A couple of weeks ago, I was fortunate enough to be able to attend the Association of Southeastern Biologists’ 71st Annual meeting held in Asheville, North Carolina. This is a pretty neat conference because every year over 1000 biologists get together and present the research that they have been working on in the past year.  The reason why I made the trip is because I did a poster presentation for my research on beaver dredged canal function and development. However, the types of questions that other researchers addressed ranged from topics such as the role of estradiol in courtship displays of Collared Manakins to the best management techniques for mountain lions in New Mexico. This conference was definitely geared towards a wide range of interests.

One particular oral presentation that I attended and thought was pretty interesting was by a graduate student named Jennifer Carman from Western Carolina University. In her study, she was investigating the morphological variation in song sparrows. What was so fascinating about this research, though, was that she was seeing real/statistically significant morphological differences between birds in rural areas and birds in urban areas. Just as Charles Darwin saw that there were many variations in the beaks of finches on the Galapagos Islands, Jennifer was seeing that the urban populations of song sparrows had larger and strong beaks than the rural populations that are just a few miles down the road. What’s more, the urban birds seemed to be much bolder than their neighbors. Jennifer was sure to let us know that this is only a preliminary study, but she is hoping to eventually find out what is causing these morphological differences. Are the urban population exposed to different food sources that require stronger beaks? She is also interested in seeing if the urban populations have higher levels of testosterone. If so, how are these populations benefiting from being more aggressive? I am interested to see how this study turns out.

A second talk that I thought was interesting actually relates a lot with what we have been doing in our own molecular genetics class. In the presentation, titled Detection of Misidentified Plants in the International Cocoa Geneback, Trinidad, James Bardsley (Towson University-Maryland) explained how he and his class used SSR analysis in order to find that 31 out of the 123 individual cocoa plants that they brought back from Trinidad were actually mislabeled. The reason for this high level of error comes from the fact that breeders are constantly trying to create new hybrids with desired characteristics. For instance, one person may decide that he was to create a crop that has a high yield and is disease resistant. He would achieve this by obtaining a “high yield” gene and a “disease resistant” gene from the gene bank and then breed them into the crop of interest. This constant intermixing of genes makes for much difficulty when trying to tell plants apart. Many of these hybrids have very similar morphological characteristics! James and his lab proved that the best way to fix this problem is to utilize molecular techniques when trying to identify a species. This is indeed a relatively expensive technique, but it is unfair that the consumers are being sold the incorrect product 25% of the time. Hopefully the cocoa companies takes this information to heart.

I’m really happy about being given the chance to attend one of these meetings. I was able to gain experience in presenting my own work, I was able to network with other scientists in the field, and I was able to learn about some pretty cool studies that are going on around the country. I highly recommend that anyone who is interested in research should go to a conference like this because they are great resources for anyone who wants to get their name out there so that they can obtain a job or go on to graduate school. This meeting was definitely worth the eight-hour drive!

How old is old? February 17, 2010

Posted by Dr. O in Biology, Evolution, Genetics.
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A short pictorial of the age of the earth both geologically and biotic-ly!

Age of the Earth: 4.5-4.6 billion years old

More info on this here.

Geological time frames

Age of bacteria, protists, & plants

Visit and ancient plant garden here.

Age of animal life: Ancient to Modern

More about the Cambrian Explosion of animals.

Age of Animals

And have a look at your ancient cousins!  What traits do you share with them?

Here we show biochemical evidence of evolutionary ancestral traits shared in the amino acid sequence of hemoglobin.

Evolution of hemoglobin

Link to hemoglobin information.