AP Biology class blog for discussing current research in Biology

Tag: death

An Electrifying Tragedy: The Death of Two Giraffes

On March 2nd, two giraffes were found dead after a thunderstorm in Rockwood, which is a private nature reserve to the west of Kimberely, South Africa. The elder, a five year old female, had a fractured skull as well as a broken ossicone (knoblike horns). These injuries indicate she had died after a direct lightning strike to the head. The second giraffe, a four year old female, was found dead  about 23 feet away from the first giraffe. There are no visible injuries on the second giraffe.

According to Ciska P.J. Scheijen, a student in the Department of Animal, Wildlife, and Grassland Sciences, wrote a paper describing the event. In the African Journal of Ecology, Scheijen describes four ways lightning can kill an animal. It can strike the animal directly, as seen in the older giraffe. It can hit as a “side flash”, which is when the lightning arches into the animal’s body after striking a nearby object. It can also kill through “touch potential” (when the animal is in contact with a lightning-struck object) or “step potential” (when the animal is in contact with lightning-struck ground). It can be inferred that the second giraffe either died from a side flash or step potential.

The giraffes were in an area without trees, making them the tallest things in the area. Knowing this, I bet you and I are wondering the same question. Yes, “Do giraffes get struck by lightning more often than other animals?” The question we all need answered!

There have been a few incidents of giraffes dying of lightning strikes, including one at Disney World’s Animal Kingdom. However, there aren’t any real concrete numbers to determine a conclusion.

Yet, Universiti Putra Malaysia electrical engineer Chandima Gones wrote a paper on animal lightning strikes. He states that “animals with a large separation between their front and back feet…are vulnerable to receive lightning injuries due to the dangerous potential differences that may built up between these feet…” Gomes also writes how taller animals (lik giraffes) are more likely to be victims of side flashes and touch potential if near a lightning struck tree. Without clear cut numbers, though, it’s hard to be sure if giraffes are struck at higher rates than other animals.

But there’s another factor involved in the deaths of the two giraffes back in March that is important. There was a thunderstorm. It was raining.

Water is a covalently bonded molecule containing two hydrogen atoms and one oxygen atom. It is a polar molecule because oxygen is more electronegative than hydrogen. Water has many cool properties. For example, it has an unusually high specific heat, making it harder to change its temperature. Because of this specific heat, it allows living creatures that are largely made of water (like us) to resist drastic changes in the body. Water keeps us alive.

Water is an extremely important molecule for life, including our own. However, when electrocuted, it could very well kill us. We all know we shouldn’t swim in a thunderstorm, but did you know wet skin has 100 times less resistance than dry? That’s right: the amount of water in the body is a huge factor in whether or not you would survive an electrical shock.

Of course, the giraffes didn’t know this. They couldn’t find shelter during the thunderstorm that ultimately led to their own demise. While we may never know if giraffes are more susceptible to electrical shocks by lightning, we do know it’s wise not to mix water and electricity.

Why Healthy People are Dying from Vaping







This article explores the new phenomenon of deaths that have arisen in relatively healthy people linked to vaping or e-cigarette use. Despite the title referring to the victims as “healthy”, there is an inherent contradiction as the people being studied in fact are using vaping as part of the daily lifestyle.  As such, they are exposing themselves to harmful contaminates and toxins including both viscous oils and chemical contaminants present in the vaping liquids that are potentially toxic to the lungs.  The vaping outbreak has led to almost 1,300 lung injuries and 26 deaths as of October 2019.

While the cause of the vaping related illnesses remains a mystery to investigators, numerous potential causes have been proposed.  Two of the major culprits, according to Dr. Michael Siegel a professor at BU School of Public Health, are thought to be either the oils or chemicals found in vaping products.  Regardless of which is the cause, both place an excessive burden on the lungs, resulting in difficulty pulping oxygen to the body tissues. As a result of the reduced oxygen, a variety of symptoms have emerged in the victims, and overall these symptoms have been coined EVALI: E-cigarette or vaping product use associated lung injury.

There are various risks associated with exposure to both the oils and the chemicals present in most vaping products. The oils, such as vitamin E Acetate are often added as thickening agents to black market vaping products which are inherently dangerous as they are not regulated by the FDA. Furthermore, the oils are thought to coat the lungs and as Dr. Siegel points out, our lungs are not designed to handle oil exposure, as the oil coats the air sacs that are needed for gas exchange and thus limit the body’s ability to acquire oxygen. The patients may experience respiratory failure, and as a result require mechanical ventilation in order to be able to breathe sufficiently. Conversely, it is also thought that chemical contaminants may be the primary problem.  Dr. Siegel draws attention to the risks associated with them including “damage to the lungs, which triggers a severe inflammatory response“.

Building on the knowledge that vaping is causing a mysterious outbreak of illnesses and deaths, researchers have taken interest in studying the problem more in depth. Samples were taken from 17 patients throughout the US who suffered from EVALI, and researchers concluded that the lung samples did not indicate that the oils were in fact the primary cause of the disease and symptoms. Instead, the samples showed evidence of injury similar to chemical pneumonitis, which results from inhalation of chemical fumes, and the authors cited in the publication in the New England Journal of Medicine that these chemicals are most likely the cause.  This information can be very promising for future research, as with this knowledge the actual cause of EVALI can be better pinpointed.

The damage found in vaping patients included very severe symptoms, with some patients even experiencing their lung cells falling off from extreme damage. The severity of this damage also led to acute respiratory distress syndrome, which allows materials such as dead cells and blood clotting proteins to enter the lung’s air sacs. The presence of these materials are quite dangerous as they prevent efficient oxygen exchange from occurring. Shockingly, this disease has an extremely high mortality rate and no known cure. This leaves people with the prospect that they may not recover, and as of right now all that can be done is temporary treatment or more importantly prevention in those portions of the population who are not vaping.  Scientists and doctors do not yet know if EVALI and associated acute respiratory distress syndrome is reversible or permanent. Thus, education is key to warn people of these risks so that they can make educated choices when being exposed to the possibility of partaking in vaping. 




First step to recovery after uncontrollable wildfires: Microbes?

As we all know, wildfires all around the world, especially out west have been burning uncontrollably. They are continuing to get larger and more unpredictable. But these fires are not only affecting humans and animals, rather they have narrowed down to affecting the tiniest of forest organisms—including bacteria and fungi– and researchers are now finding that some of the microbes are “thriving”.

A study last week reported that “that populations of several bacterial and fungal species increased after severe wildfires in the boreal forests of the Northwest Territories and Alberta in Canada.” Studies like these and others such as the effect of smoke on the distribution of microbes, “give researchers a clearer picture of how wildfires change microbial communities”, and can possibly help them predict how ecosystems will recover after blazing flames. “Microbes help to maintain ecosystem health by decomposing organic matter and readying nutrients for plants to absorb”. For example, because certain fungi and bacteria have specific relationships with plants, it makes it possible to predict which nutrients will be available in an area.

Image result for wildfireIn order to test what they had predicted researchers collected samples from 62 sites about a year after 50 of them had been damaged by fire in 2014 in forests of two Canadian provinces. They found that certain bacteria in the Massilia and Arthrobacter genera were more present after than before the fires. This bacteria usually shows up in cucumber root and seed, and some researchers are predicting that there might be some growth of vegetation of that kind in the future when the forests begin to recover.

It is predicted that microbes “use fire to colonize new territory is by hitching a ride on small particles of ash or dust in plumes of smoke”. In a study published last November, Leda and her team conducted a study and found that “the microbes present in the smoke differed from those lingering in ambient air”. The microbes getting caught in the smoke she predicts can help plant growth in faraway regions.

There is a downside. It has been detected that some fungus, such as Phytophthora ramorum, cause sudden oak death. Another negative is the smoke that the firefighters, other ER personal, and people inhale after and during the fires could contain hazardous microbes. These can lead to lung problems and allergens.

Microbes are not often spoken about when wildfires sweep through, but they surprisingly have more impact than you may think. When entire ecosystems are reduced to ash, microbes determine the first step on the road to recovery.

A Baby Beetle’s Nursery is.. In a Dead Mouse?!

Two Parent Burying Beetles in a Dead Rodent! Gross!

Typically, death for animals is experienced at the end of one’s life, but this is reversed for a certain species of carrion beetle, Nicrophorus vespilloides or burying beetle, in which infant beetles are born and raised within dead mice carcasses. In this mice carcass, parent beetles frequently tend to the dead animal by soaking it with their own oral and anal secretions, providing the baby beetle with a much needed dark microbial film. This bacterial goo actually closely resembles the parent beetle’s gut microbiomes, allowing for the baby beetle to truly thrive as an offspring of this beetle.

But why give these baby beetles this goo within a dead carcass? What benefit would that ever give to an insect?

In every living thing, there is sphere of personal bacteria that provide much needed life benefits as well as qualities like your own stench. Plus, bacteria can even join together through various forms of cellular communication, making an almost impenetrable microfilm biome for bacteria to live in, as seen in plaque on human teeth. This same function is what helps support infant beetles with necessary nutrients and life benefits by keeping the cadaver fresh and capable of sustaining youngster life. Plus, it even causes dead bodies to smell actually not terrible, but instead more pleasant! Crazy! “What burying beetle parents can do with a small dead animal is remarkable,” says coauthor Shantanu Shukla of the Max Planck Institute for Chemical Ecology in Jena, Germany.  “It looks different. It smells different. It’s completely transformed by the beetles.”

If these insects aren’t exposed to these microbiomes as a child, there could be some serious detrimental effects. As shown by Shukla’s lab work, larvae grown in cadavers that were swept clean of biofilm by Shukla and her colleagues used their food less efficiently and gained less weight (“roughly third less weight per gram than those who had their parents goo”).

But, the parents are not the only ones who manipulate the carcass, which can be seen here. As parent beetles and tended to their goo in the body and guarding their children, the infant beetles also add their own secretions to the dead mouse and also eat away the bacteria as well as the entire mouse body. “What will remain is the tail of the mouse,” Shukla says, “and the skull and a few pieces of skin.”

Isn’t it simply crazy how much bacteria can contribute to the growth of a baby insect as well as its impact on even a dead animal? Comment below about what YOU think about this!

Tiny Devils Take Down Gentle Giants all due to Climate Change!

File:Alce (Alces alces), Potter marsh, Alaska, Estados Unidos, 2017-08-22, DD 139.jpg

A innocent female moose, about to be attacked by an onset of terrible parasite in Northeast Canada.

Winter Ticks, not containing Lyme Disease or other Human-harming diseases, are rising exponentially in population throughout New England and Canada, all due to increasingly warmer and snow-free springs and later winters everywhere. As a result, an unlikely species in this region is being targeted by these tick epizootics, Moose, because ticks search for hosts in the fall and other warmer temperatures and stop once freezing weather and snow befalls the land. Yet, when these conditions occur much later, it gives these ticks more time to feast on peaceful animals, and also giving more time for female ticks to fall off its host and create tons more larvae, not making this issue any better. As these raisin sized parasites latch onto to these large creatures, draining so much blood at a time that they simply are unable to function anymore and weakly fall, succumbing to the environment, other predators, or even more ticks. But it’s not simply a few ticks, no, these moose can carry up to around 90,000 ticks! Because of this, there has been “an unprecedented 70 percent death rate of calves over a three-year period” according to a similar source from the University of New Hampshire. Plus, this problem has gotten so bad that now a threatened species in this region of British Columbia, the boreal Caribou, are being eaten alive as well!” If blood loss from heavy tick loads does not directly kill animals, it can make them susceptible to other health risks, Schwantje adds in the original source. “They have spent so much time scratching and chewing on themselves that they haven’t been feeding, so they are in poor body condition,” she says, even with tremendous hair loss that they become basically unrecognizable.

File:Ixodus ricinus 5x.jpg

An example of one of these detrimental winter ticks, a female engorged in size with blood and larvae, ready to reproduce .

But How Can This Be Stopped?

Currently, researchers are offering a multitude of solutions to help save these wonderful species from these terrifying parasites, as Swantje says that “They have huge cultural and nutritional value to our First Nations, And when moose forage in wetlands, they help release nutrients into the environment and make them available to other plants and organisms, studies have shown”, one solution can even be seen here. One possibility is to continuously treat half of the moose with anti-parasite gel and pills that make attached ticks drop from their bodies in order to isolate specifically what the ticks do and don’t do to harm these moose. The other possibility is a highly unlikely one, hunt the moose. Researcher Peter Pekins suggests that “issuing more moose-hunting permits in strategically selected areas” could essentially starve out the ticks in certain areas, yet it is argued that this would only benefit the environment short term, as the climate will continue to warm leading to the growth of more and more ticks.

Who know, if this isn’t stopped soon, ticks will continue to grow in population and maybe even take down us humans! Save the moose (and the caribou)!

Do You Really Want that Third Piece of Bacon?

This is a picture of a hamburger, which is a form of red meat often consumed by individuals everywhere. Found on Wikimedia Commons.

How many  people do you know that eat bacon every day?

What about a hamburger?

Did you know that the Harvard School of Public Health has recently discovered that red meat consumption can strongly contribute to cardiovascular disease and cancer, ending one’s life prematurely? These days, it is much healthier to eat “poultry, nuts, fish and legumes.” We need alternative sources of protein.

According to Nutrition researcher and author An Pan, who works at the Harvard School of Public Health,

“…eating high amounts of red meat has been associated with type 2 diabetes, coronary heart disease, stroke and certain cancers in other studies.”

It is scary to think that every time someone consumes red meat daily, there is a 13% increased chance of death. Eating processed meat is even worse because if eaten daily, there is a 20% increased chance of death. Every time someone consumes heme iron, carcinogens that are released from the meat during cooking, saturated fat, sodium and nitrates from his or her steak, these risk percentages rise. It has been researched that these risks can be weighted more heavily depending on “age, body mass index, family history of heart disease or major cancers.”

Now, we know that the protein replacements of fish (7%), poultry (14%), nuts (19%), legumes (10%), low-fat dairy products (10%) and whole grain (14%) have great percentages for lower risks of premature death. If people “eat less than 0.5 serving per day of red meat, 9.3% of deaths in men and 7.6% of deaths in women can be prevented.”

Mortality is an important factor for every individual to consider. Why waste life away to eat a slice of bacon each morning?



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