Wednesday, February 29, 2012

Global Warming Causing Infidelity in Birds?

When climate conditions become more variable, birds are more likely to ‘cheat on’ and ‘divorce’ their mates. The hypothesized reason is that birds may be seeking out a greater diversity in genes for their offspring. An unstable climate could be deadly for birds, so breeding with a wider range of mates could increase the likelihood that their offspring are fit for the new environment.

Over 90% of bird species regularly engage in social monogamy. A male and a female will pair off, sharing territory and engaging in social pair behavior for at least one breeding season, although many will remain monogamous for many years. However, researchers have found that some chicks are actually fathered by other birds than the ones who act like their fathers, taking care of the nest. Also, a pair of birds may act monogamous for a few years, and then ‘divorce’, finding other mates in subsequent years. Exposure to a variable climate drastically increases the chances that a bird will engage in extra-pair copulations or will find a new mate for the season.

For example, birds with large beaks are sexually selected for in dry climates, where they are better at eating large seeds; birds with small beaks are sexually selected for in rainy climates, where they are better at eating tiny seeds. It is easy for a female to select her mate in a stable wet or dry climate, but if the climate is variable, she will seek variability. This occurrence is becoming more and more prevalent with recent global warming.

http://www.scientificamerican.com/article.cfm?id=climate-change-increases-mates-swapping-birds


Posted by Erica Fitzpatrick (1)

Secrets to Immortality

Everything must come to an end one day. At one point everything and everyone will die. Mythology features a whole plethora of immortal gods but we can never emulate them.

Or can we?

A Science Daily article talks about researchers from the University of Nottingham have been studying two types of planarians (flatworms), an asexual one and a sexual one. These worms have nearly infinite regenerative abilities, even able to regrow brains. According to the research, it turns out that it has something to do with the stem cells of these worms.

Normally, when stem cells divide they eventually age, which causes them to loss their ability to divide. This aging is caused by shortened telomeres. Telomeres are “caps” at the end of chromosomes and they work like the aglets of a shoelace. Whenever cells divide DNA must be replicated and each time this happens the telomeres shorten. When these telomeres get too short the cell can no longer divide. There is an enzyme called telomerase which can maintain these telomeres. Humans have them, but they are only active during early development.

The research was centered on a planarian version of the gene that controls telomerase. When the gene was turned down, the telomeres of the planarian was shortened. After that, they measure gene activity and telomere length and saw that asexual worms increased the telomerase gene activity considerably when regenerating, which lets them maintain telomere when they make new tissues. However, this increased telomerase activity was not seen in the sexual worms, despite the fact that they are just as regenerative as the asexual worms. The researcher plan on continuing their research on this topic to find just what is going on with the sexual worms.

This research really is a breakthrough. While we might not ever be truly immortal, being able to regenerate body parts could have valuable medicinal application.

http://www.sciencedaily.com/releases/2012/02/120227152612.htm

Posted by Joseph Frimpong Feb 29, 2012 (Group A (2))

Another species finding meat hard to resist?

Cute, cuddly, and furry. It’s endangered and has done kung fu on the silver screen recently. What am I talking about? Pandas of course! These adorable creatures which spend their time laying around and gnawing on bamboo shoots, are the emblem of China. Due to deforestation, pandas are considered a conservation reliant endangered species.

Recently, pandas have caused quite a stir in the science community. An article on the 28th of December 2011 from the DailyMail reported that these creatures eat meat! Is this one of the biggest deceptions in history? Has the entire species of Pandas decided to fool us by gnawing on bamboos during the day when we visit them at the zoo, only to pull out a whole rack of ribs from their hideout and snack on them at night? A wild panda was recently caught on camera eating a dead antelope around the region of Sichuan, China. But according to the WWF (world wildlife fund), pandas do in fact have a digestive system of a carnivore. (Further investigation shows that they belong to the order canivora.)Therefore, this shouldn't come as a surprise to us, even though bamboo is 99% of their diet. That said, they have evolved for millions of years from living in bamboo forests in order to be able to better digest the cellulose from bamboos. In order for them to stay healthy, they have to eat up to 14kg of bamboo daily, because bamboos hardly have any protein or energy in them. But, while this certainly satisfied panda might have been caught red pawed eating a dead antelope, it has been suggested that it may have just chanced upon it, instead of hunting and killing it.

Pandas, sadly, are an endangered species. However, efforts to increase its population are ongoing. Government officials have released 6 of 108 pandas in captivity into a controlled wilderness in the southwest province of Sichuan, which spans over 2,000 acres. These 108 pandas, bred through artificial insemination, were raised by the Chengdu Giant Panda Rehabilitation Project and they plan to slowly release these pandas back into their natural habitat in the next 50 years. Why, you might ask, must the Pandas be bred through artificial insemination? Well, the reason is because females ovulate just once yearly, and can only conceive during a period of two to three days.

In conclusion, we should do more to help protect endangered species, such as the panda, and their habitat. Donating money to organizations that fight for this cause isn’t the only way. We can do our part in preventing these species from losing their habitat or even from being hunted or killed by reducing and recycling, avoid fur and leather products, stop littering in river or seas, and using or supporting a reduce in the usage of herbicides and pesticides.

No Need for a Pulse

The beating of our heart is equated only with the breathing of our lungs when it comes to functional importance, and far surpasses it in number of metaphors. But there are people - just a few - who are walking around with a heart that doesn't beat. Instead, they have two small Archimedes's screws sewn in place of their ventricles that propel their blood throughout the body with no pulse - at all. After all the years of trying to imitate the hearts pump, an entirely different mechanism seems to have succeeded. In the Popular Science article, No Pulse: How Doctors Reinvented the Human Heart, they liken the uniqueness of the mechanism to the discovery of human flight, which also ignores the blueprint given by nature. For now, the device is more likely to serve as an aid to a failing heart than as a replacement. In some cases, though, it has taken over full responsibility for the circulation of blood. It's hopeful that heart surgery may not rely solely on a transplant list in the future.

Posted by James Fargnoli(4)

Can Biofuel be made from a Mutated Plant?

Seth DeBolt, a professor of horticulture from the university of Kentucky, has been studying different mutations of cellulose in plants. Plants have cell walls made up of cellulose and in most plants the cellulose is made of thick crystallized sugars forming strong plant cell walls. Plants with weak cell walls are vulnerable to enzymatic breakdown, forming sugars that can be fermented and used as biofuel.
DeBolt has been trying to different methods to reduce the cellulose in plants so he can create a source of biofuel that is not harmful to the environment. DeBolt and his team were successful in decreasing cellulose content in these mutant cell walls. By discovering a new method of obtaining biofuel energy sources such as ethanol and diesel, the world can run these new efficient energy sources instead of burning through fossil fuels.

http://www.sciencedaily.com/releases/2012/02/120228152158.htm

Posted by Khoa Chu (4)

NOWHERE TO HIDE: TIGERS THREATENED BY HUMAN DESTRUCTION OF GROUNDCOVER

Tigers are a beloved species that is unfortunately facing extinction in the tough world of today. Population numbers are at record lows and humans are still killing them off and claiming self defense. Humans killing them however isn’t the sole reason that these animals now face extinction. One major factor contributing to their rapid decline is human destruction of groundcover or deforestation. With the growing human population and demand for hard wood, forests are disappearing by the acre on a daily basis. Being ambush predators, thick, heavy vegetation is what tigers thrive on.

With scarce vegetation the tigers have less and less places to hide for an ambush attack. This is greatly impacting the tigers as most of them are dying of starvation because their element of surprise is almost completely eliminated and they now find it very difficult to capture prey. In Indonesia, the Sumatran tiger is a critically endangered species with an estimated 400 tigers left in the wild. Although Indonesia does have a lot of forest protected for wildlife conservation, this protected forest only accounts for a fraction of the tigers range. This leaves many tigers at risk for exposure to humans.

Tigers generally want to stay away from humans as much as possible. Humans tend to think of tigers as dangerous and therefore many natives kill them if they are nearby and feel threatened by them. Also, many natural forests are being cut down to make room for plantations. This is pushing the tigers out of their home and further and further out of their comfort zone. They now have to adapt their lifestyle in order to survive and that is why most will start to die off. A major push needs to take place in protecting more national forests in order for the tiger population to survive. Local governments really need to step up and take action soon or else there is a good chance that tigers will go extinct altogether in as short a period as our lifetime.


http://www.sciencedaily.com/releases/2012/02/120228140502.htm


Posted by Nicco Ciccolini(4)

NO HEMOGLOBIN NECESSARY

The mackerel ice fish, also known as the crocodile ice fish due to its teeth and elongated head, is very unique among fish. It is also unique among the entire group of vertebrates. The mackerel ice fish is the only vertebrate that lacks hemoglobin. First recorded in 1954, the mackerel ice fish has nearly colorless blood due to this lack of hemoglobin. Hemoglobin is found in red blood cells and is what allows vertebrates to carry oxygen in their blood. Without hemoglobin, oxygen cannot attach. So how do these fish get oxygen to through their bodies?

Part of their name “ice fish” is given because these fish live in the frigid waters of Antarctica. The solubility of gases increases as the temperature decreases thus making the extremely cold ocean water where these fish live exceptionally oxygen rich. The salt in the water of the ocean allows the water to reach temperatures far below the normal freezing point of water without turning into ice. The colder the water, the higher the solubility of oxygen gas. Many animals would freeze to death from their blood freezing at such a temperature. However the mackerel ice fish has a chemical “antifreeze” in its blood that prevents ice crystals from forming and allows the fish to live comfortably at extremely low temperatures. A high oxygen concentration in the water is important because the mackerel ice fish’s lack of hemoglobin lowers its oxygen-carrying capacity to less than 10% of that in closely related red-blooded species of fish. However, several anatomical modifications have occurred over time and the ice fish have evolved their body structures to adapt to their environment.

Ice fish have a denser concentration of veins and arteries supplying their high oxygen demand tissues. They also have large capillaries and blood volumes that are four times that of closely related red-blooded fish. Another feature of their body that assists with high oxygen delivery is the size of the heart. Ice fish have large hearts that beat almost twice as fast as their relatives and allow them to circulate a lot of blood very quickly. The ice fish also has a rather low metabolic rate and thus its need for oxygen is lower than that of other fish. It has also been speculated that they are capable of absorbing some oxygen directly through their skin.

I could not find any current research studies involving these fish, however I’m sure there are many interesting studies that could be done with them.

http://eol.org/pages/206610/overview


Posted By Erica Bonnell(1)

Wednesday, February 22, 2012

Sqeezed Into Smaller Spaces, Koalas Now Face Deadly Disease

When picturing a koala, one thinks of a cute and
cuddly animal, one that causes no harm to anyone. Sadly, the koala, “one of Australia’s
most treasured creatures”, faces trouble from climate change, environment and
habitat loss as well as a new and concerning factor, bacterial disease. These harmless cute creatures are being forced into smaller and smaller habitats and regions of Australia seriously
endangering their health and presence on earth. Is there anything we can do to prevent this
disease from killing off koalas?

Surprisingly, the disease harming koalas is chlamydia, known to humans as a venereal, yet curable disease, and one that is detrimental to the life of a koala. Chlamydia is known to have already affected the lives of at least 50 percent of the Koalas in Queensland, Australia, yet probably many more. One may ask how a disease curable in humans could be causing such devastation to the koalas. One must understand that the bacteria strains transmitted through mating, birth or fighting are known as Chlamydia pecorum and pneumonia are different than the bacterial strains which effect humans. The symptoms of these strains can cause eye infections or blindness which greatly hinders their ability to find food and protect themselves, the
bacteria can also cause respiratory and cyst issues where in some cases the koalas
may become infertile greatly heightening the chance of endangerment. What sets
this form of chlamydia apart from what humans’ contract is the fact that it is
paired with another disease. A second disease known as the koala retrovirus is said to be carried by almost all of the koala’s in Queensland, greatly hindering their immune not allowing them to
properly fight off chlamydia. Although there is not a cure for the retrovirus, researchers have been formulating a vaccine that has been successful and is safe for the koalas. This vaccine could
be the answer to cure this disease that when paired with the retrovirus turns deadly. Although difficult to distribute as it seems impossible to distribute it to every koala, the researchers believe this vaccine to save the koalas.

Koalas are the beloved creatures of Australia yet it does not seem as if there is a lot of effort being put in to eliminate this disease from all koalas’s to prevent spread. We should work to further the research of the vaccine to finally end this disease. However, should there actually be an increased effort to save the koalas? The concern comes not only for their safety, but because of the fear that this disease could be transmitted to other species. Should we be worried that this disease
could lead to an epidemic?

http://www.nytimes.com/2012/02/21/science/queensland-koalas-hit-by-chlamydia-infections.html?_r=1&ref=science

Tara Reynolds (3)

Robots in your DNA


I'm a fan of nanotechnology, its a fascinating field with long reaching applications. I found this article mentioning that researchers at the Wyss Institute for Bio bioengineering have developed something quite interesting. Its a robot, a really small one. This nanorobot is made from DNA, and is modeled after the body's own immune system. Its function is to seek out specific cell targets within a mixture of different cell types. It then goes about delivering important instructions to the cells, like telling a cancer cell to self destruct for example.
Since the nanorobot is inspired by the body's immune system it will not be targeted for destruction by white blood cells. Also with this "instruction" ability of it's it can be huge for treating disease. The nanorobots can be considered extensions of the body's own natural immune system. The technology has already been tested on leukemia and lymphoma cells with each being successful in activating the cells "suicide switch". This technology might get rid of the practice of radiation treatment and chemo for cancer patients. Very cool.

posted by Dorian Pillari (3)

Tuesday, February 21, 2012

Sea Otters and How They Affect the Ecosystem

Sea otters are well known for being adorable furry creatures that eat constantly while floating leisurely on their backs. They also are what we call keystone species that have great impact on their respective environments; these can be negative or positive but usually the latter. So how big of a negative impact could a constantly consuming lazy creature like the otter have on the environment? Massive. Sea Otters can eat upwards to 35% of their body weight on food. Most of their food sources come from other sea life that eats kelp. Kelp forests are vast and diverse ecosystems that many creatures use to breed, and breed very productively. There are fields of these kelp forests off California coast, and sea otters are also present as a result.

Sea otters keep these environments diverse and flourishing by eating a variety of sea life, such as crabs, sea urchins, lobster, etc. that keep the balance of the life cycle of sea life living in the kelp forests. Multiple times in history, humans have tried to take otters out of the ecosystem believing they were negatively effecting the environment because of their voracious appetite. Instead, humans did the exact opposite of what they were intending to accomplish. Humans thought that sea otters were eating too much of the fish that they themselves wanted to harvest, so they hunted sea otters to near record low levels. Sea urchin population exploded as a result because of the lack of sea otters that were their natural predators. As a result, the sea urchins ate vast quantities of kelp unchecked, destroying the habitat of many diverse breeds of fish who use it as a mating ground. Fish populations plummeted; the only way to counteract this was to bring back the keystone species, sea otters. Once they brought back the sea otters by protecting them and stop the hunting, the environment gradually recovered. An ecosystem is like a fine watch, you can’t take out a piece, no matter how small or apparently insignificant without damaging the whole thing. Sea otters are one example of what can happen when you take out a big piece.

Article:

http://www.otterproject.org/site/pp.asp?c=8pIKIYMIG&b=33677

http://www.exploringnature.org/db/detail.php?dbID=7&detID=77

Posted By Andy Zou (C)


If You’re in the Infrared, You’re Dead: Molecular Mechanisms of Predation and Infrared Sensory in Snakes

There are over 3000 snake species that have been identified worldwide, and about 600 of those species are poisonous1. All snakes possess interesting physiological characteristics bearing biologically important questions about snake morphology that continues to promote research about how snakes move, their evolution, how some snakes create and use their venoms, how snakes capture their prey and its relative importance to benefitting human society. In an article published March 2010, Molecular Basis of Infrared Detection by Snakes, by Elana O. Gracheva et. al, Gracheva, she and her team attempt to answer some of these questions by studying how venomous pit vipers are able to use their unique pit sensory system to detect their prey by utilizing infrared radiation.

Most people are aware of simple snake anatomy: they are legless reptiles with scales that literally ‘snake’ their way around. In the article, the authors introduce the reader with information about how pit vipers detect their prey, without intimidating the reader with overly complex concepts or science jargon, peaking the reader’s curiosity as to how snakes are able to detect their prey.

“Snakes possess a unique sensory system for detecting infrared radiation, enabling them to generate a ‘thermal image’ of predators or prey. Infrared signals are initially received by the pit organ, a highly specialized facial structure that is innervated by nerve fibers of the somatosensory system. How this organ detects and transduces infrared signals into nerve impulses is not known.”

Needless to say, the article doesn't fail to bring their audience to a higher concepts and biological understanding to support their research and present their methods for testing the actual molecular mechanisms of the pit organ, building on existing research that pit vipers possess infrared sensory organs that aid in hunting their prey. The authors provide detailed information about trigeminal fibers to clearly explain their reasoning and how it directed their research to focus on transcriptome profiling to identify TRPA1 as a “candidate infrared detector” based on how infrared radiation can be detected and the limited genome information of pit vipers.

TRPAs are transient receptor potential cation channels that are present in human cells and many animal cells, including snakes. In humans, the receptor is primarily responsible for the detection of pain, cold and environmental irritants. In snakes, they detect infrared radiation. The authors compared trigeminal ganglia (TG) and dorsal root ganglia (DRG) anatomy of pit snakes to those of humans and other snakes that lack pit organs, and compared their gene expression profiles, noting that TG fibers in pit snakes are larger while gene expression profiles are fairly similar to those of humans, thus “marked differences in snakes should reflect functional specialization associated with infrared detection.” By using sequencing to compare profiling between TG and DRG, they found that TRPA1 channel in the diamondback rattlesnake was “was enriched 400-fold in TG” and that they lacked transcripts for TRPA1’s in their DRG, supporting their hypothesis that TRPA1 plays a critical role in the function of infrared sensing in the TG. The authors used high resolution imaging to illustrate these findings, enhancing the readers’ understanding and appreciation for the dense information presented. It also leaves the reader wondering if human gene sequences similar to those of TG fibers in pit snakes could be enhanced to give us truly superhuman power. Maybe flashlights would go extinct and our children would gawk at them in museums.

Overall, the authors do a good job of explaining their research and presenting information that supports their hypothesis that TRP channels are responsible for infrared radiation detection in certain snakes species and why infrared radiation detection is not possible in other species with TRP channels. Despite the explanation, I still couldn't stop wondering if human gene sequences similar to those of TG fibers in pit snakes could be enhanced to give us a truly superhuman power. Maybe flashlights would go extinct and our children would gawk at them in museums. After all, the article isn't convincing enough. It doesn't prove TRP channels are solely responsible for the unique infrared radiation ability to capture prey, exactly how it evolved or why it evolved in certain species with TRP channels than others. The research has a lot of potential, and the outcomes and additional research that it could promote were not discussed in the article’s discussion. The only obvious ‘benefits’ of this research that were apparent to me seemed to concern the development of modern warfare and weapons. The article could have offered information on why this research was important and its implications rather than implying that the research was motivated by science not knowing why or how infrared radiation detection functions. Although human curiosity is great, research is expensive, and some of the motives for the research and greater analysis and discussion of its significance would broaden the reader’s understanding and probe the scientific community to continue researching such a fascinating topic that has been relatively dormant for half a century.


Posted by: Karen-Maria Melendez (2)

References:

1) http://apps.who.int/bloodproducts/snakeantivenoms/database/

2) Gracheva, Elena O., Nicolas T. Ingolia, Yvonne M. Kelly, Julio F. Cordero-Morales, Gunther Hollopeter, Alexander T. Chesler, Elda E. Sanchez, John C. Perez, Johnathan S. Weissman, and David Julius. "Molecular Basis of Infrared Detection by Snakes." Nature 464.1006-1011 (2010). http://www.nature.com.silk.library.umass.edu/nature/journal/v464/n7291/full/nature08943.html


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