Naked mole rats are affectionately known as an odd freak of nature. They can live for up to 30 years (which is absolutely astonishing for a rodent its size), are resistant to pain, and are practically immune to cancer (only two known individuals ever were found with cancer). Now, scientists have discovered another interesting fact regarding these rodents: they can last 18 minutes without oxygen.
Most people can’t last 2 minutes without gasping for air, so it’s quite a shock that a small rodent can do this for 18 minutes! Granted, the naked mole rats lose consciousness nearing the 18 minute mark, but they completely recover after being exposed to normal oxygen levels. They have a handy trick that has been evolved throughout their generations. Their secret is that they switch from using glucose as energy to using fructose as energy. To break down sugar, humans as well as almost every other mammal go through glycolysis, which uses up oxygen. Glycolysis happens immediately during the breakdown of glucose. However, with fructose, the process of glycolysis happens in later steps. This means that the production of energy can go on without the use of oxygen for a time.
It makes sense that a different kind of energy production would evolve among naked mole rats. They live and burrow underground with as many as 300 other naked mole rats. This makes oxygen a bit of luxury. Having a way to survive in an environment with a much lower oxygen concentration would be extremely beneficial.
Long ago, 375 million years to be exact, there swam a small fish swam in a large body of water. This was no ordinary fish, even by the standards of 375 million years ago. This fish had rudimentary wrists.
Now, you may be thinking to yourself, what is so special about a fish with a wrist? Understandable considering that most people, myself included, are not experts on fish anatomy. The bones in a fish’s fin do not make up a wrist. What makes this discovery so important? This fish, the Tiktaalik is currently the biggest link between oceanic life and the first animals to walk on land.
Tiktaalik had a flat head similar to alligators as well as a neck. Fish have a more rounded head and do not have a neck because their vertebrae connect their heads and their spines. This anatomical difference was probably the first tip off to archaeologists that this was no ordinary fossil. They were even more excited when they analyzed it further in the laboratory. There they discovered the rudimentary wrist. Having a wrist allowed this fish to be able to push off of surfaces, most likely near the bottom of a shallow area of water. In other words, this fish had the ability to crawl. Although this fish had no lungs, it was still possibly capable of crawling above water, even if it couldn’t survive up there yet. This fish is almost certainly an ancestor of the first beings to crawl out of the water.
Everyone knows just how bad an evolved bacteria or virus can be; I even wrote about Malaria, a commonly known virus-caused disease. However, a lesser known killer has been destroying animal, plant, and probably humans as well: fungus.
As those who have been following know, I have been reading Elizabeth Kolbert’s , “The Sixth Extinction: An Unnatural History”. As it comes to a close, I can’t help but be shocked how history can continually repeat itself. Kolbert gave two instances in detail in her book where an advanced fungal blight has spread throughout different species and quickly began killing.
The first is the golden tree frog of Panama also known as the Panamanian golden frog. These frogs were everywhere around Panama, and not just the wild either. These frogs have a cultural value there and are a symbol of luck, which is probably why they are printed on lottery tickets among other merchandise. It’s honestly surprising how long it took for people to realize the population was declining, and fast. By the time people began to set up little refugee sites for these frogs, thousands had died. A fungus was the cause of not only the huge decline of this frog, but lots of other amphibians around the world. Only two frog species were found to be resistant to the fungus: African Clawed Frogs and North American Bullfrogs. This suggested that the fungus co-evolved within these species, attempting to get the upper-hand. These two frogs are also well known to move around the world either to be consumed, used for medicinal purposes, or as pets. Odds are an infected individual spread the evolved fungus to another amphibian who had no natural resistance to it, quickly killing and spreading.
There are, unfortunately, other occasions of such an event happening in other species, bats to be precise. White-nose-syndrome is also a fungal infection, but found in bat species. It was also a very quick killer, partly because of how social bats are. It spread rapidly from one cave to another, it was safe to say that once it arrived in one cave, by the next day every bat in that cave had it. Again, certain species of bat, found in Europe, are resistant to the disease, but still carry it. European spelunkers wishing to go into and explore caves visited New York one day, and the fungus on their clothes managed to spread to a bat, and the rest is history.
To those who don’t know, or don’t know too much about, the Huns were a nomadic tribe. They were a skilled group of warriors under the leadership of Attila the Hun. They travelled very far to the east and took in many different ethnical groups along the way and were considered to be one of the primary causes for the fall of the Roman Empire. Even before the fall of the Roman Empire, they were considered to be ruthless, brutal savages. However, recent studies by Dr. Susanne Hakenbeck and her team have shown they may not have been as hostile as history seems to suggest.
The diet of most Romans at the time consisted mainly of grains and vegetables, while the diet of most Huns was centered around the meat obtained from their herding lifestyle. However, on the eastern border of the Roman Empire, where Romans and Huns lived fairly close together, there was something different occurring. Here, the Romans had incorporated meat into their diet and the Huns were found to have smaller amounts of livestock and grew crops. This indicates that not only did the Huns and Romans share a relatively close amount of space together, but they also shared with each other aspects of each other’s cultures. It also suggests that Huns and other herding communities were very adaptive to their environment. This makes sense, as not only would they need grains to feed themselves, but their horses and other livestock as well.
Dr. Hakenbeck studies the skeletons of 234 individuals from five excavation sites. They were able to find evidence of Huns, like bronze weaponry and most notable the shape of their skulls. Huns had their children’s heads binded the during childhood which caused easy to identify elongated braincases. By taking and comparing measurements of ratios of specific forms of carbon, nitrogen and oxygen in teeth and ribs as well as strontium, Dr. Hackenback was able to find out that the Huns near these Roman sites ate a lot of cultivated plants, meat, and milk and that between 30-50 percent of the skeletons were not raised in the immediate area. This means that 50-70 percent of the people buried in those sites were born and raised there, which could possibly be a sign that Huns were able to recruit some Romans.
In the past week, I have managed to conduct an interview with Dr. Ralston, who was kind enough to recount some of her previous research. Dr. Ralston conducted a study on osteochondritis dissecans (OCD), which is Developmental Orthopedic Disease that causes horses’ bones to be weak. Her team gathered a large sample size of very similar horses (both in genetics and how they were brought up). The only difference was that of the mothers, one mother would have OCD and the other would not. They took blood samples of the horses, and found interesting results.
To obtain this data, Dr. Ralston and her team used a process called Nuclear Magnetic Resonance (NMR). NMR is an analytical process that used different cells
magnetic fields. When introduced to NMR’s own magnetic fields, it creates a spectrum that can be measured.
The first result is that the data differed in a month period, which gave evidence that glucose levels were affected by the season/monthly period. The second of which was even more interesting; horses with OCD tended to have higher amounts of essential amino acids than nonessential amino acids. Normally, the horses would turn their essential amino acids into nonessential amino acids via a metabolic pathway. Since the levels of essential amino acids were so high, Dr. Ralston deduced that pathway that caused essential amino acids to turn into nonessential amino acids was probably malfunctioning in horses with OCD, which may be a reason why OCD exists.
Another interesting bit of research that Dr. Ralston has worked on deals with Diabetes. Insulin abnormalities are common in young horses, so it has been proposed that horses could make an apt model for the benefit of humans suffering from type 2 diabetes. Although more research needs to be done, the possibility is still there.
Evolution is one of life’s most powerful tools. Fueled by natural selection, it allows life to improve over generations. It makes people wonder why certain hereditary diseases are so common. However, sometime we have to take a closer look.
One classic example is Sickle Cell Anemia, or sickle cell disease (SCD), which is a hereditary disease that causes blood cells to have an irregular, sickle-like shape instead of their normal round shape. This causes complications in carrying oxygen and a risk of blood cells getting stuck and clogging blood vessels. It is common in certain parts of Africa and Asia. It would seem odd that a deadly hereditary disease would be common, but there is a secret this diseases possesses.
SCD is recessive (having 2 recessive alleles). However, if a person is heterozygous for this disease (one recessive and one dominant allele), they are actually resistant to malaria. The parasite that causes malaria has a hard time getting into sickle-shaped cells. Heterozygous individuals have some of their cells sickle shaped, but not enough to exhibit symptoms. Therefore, it is advantageous for a person to be heterozygous for SCD. Apparently, the resistance to malaria is worth the risk of having SCD.
SCD isn’t the only disease that is resistant to malaria. Hemoglobin E disease, common in Southeast Asia, is similar to sickle cell anemia, except that its symptoms are much milder. For some people, it’s a benign disease, but its effect on malaria is still the same.
However, despite being a much better alternative, it isn’t very common in Africa. This is mostly due to the fact that, even if it’s imperfect, sickle cell anemia is already there (The Power of Random). Despite being a better alternative because of its milder symptoms, the niche of malaria-prevention has already been filled and prospered for many generations. It will take a lot of time for Hemoglobin E disease to be more common in Africa, if it ever becomes more common.
Animal studies have always felt more personal than other forms of studies. Geography, chemistry, and physics are all well an good, but ecology will always be this writer’s personal favorite.
This sentiment is shared be Dr. Sarah Ralston, a current professor at Rutgers University. Specifically, her interest and research subject revolves around equines. Her work with horses has gotten her a lot of attention and two awards/honors, as well as allowing her the opportunity to take part in many national equine and veterinary committees. The two committees she is currently apart of are the New Jersey Veterinary Medical Education Contract Program Advisory Committee and the National Association of Equine Affiliated Academics: working group for development of NAEAA ‘alumni’ survey tool.
Dr. Ralston got her bachelors, doctorate, and her veterinary license (School of Veterinary Medicine) at the University of Pennsylvania. Other forms of education include her Masters gotten from Colorado State University in Fort Collins and her Board Certification at the American College of Veterinary Nutrition.
One study she has taken a part in was her research on glucose/insulin metabolism and growth in horses. A link was found between a high-grain (high carbohydrate) diet and to developmental orthopedic diseases in young horses. For older horses, this kind of diet has also been linked with a disease known as laminitis. Due to this link, their is research studying metabolic alterations between different diet: one high in carbohydrates and one low in carbohydrates. To do this, they use a process known as nuclear magnetic resonance spectroscopy (NMR) to better collect data.