Mystical “Catnip” May 3, 2011Posted by mhostetler099 in Behavior, Biology, Chemistry, Health, Physiology.
add a comment
So what is it about “catnip” that makes cats crazy, mosquitoes fly away and at the same time has seemingly no effect on human beings? In actuality, the better question is what are the distinguishing factors allow different organisms to interpret “catnip’s” chemical signal differently or not at all.
The 6th Sense (the vomeronasal organ in cats)
It is well documented that all mammals posses 5 senses (sight, taste, touch, smell, hearing); BUT could mammals have a 6th sense?! Some scientists would say YES and pinpoint this sense to be related to the mysterious vomeronasal organ located above the roof of the mouth. This sensory organ is attributed to sensing chemical signals from other organisms and the environment known as pheromones. The vomeronasal organ is present in most mammals and is considered a chemoreceptor organ which exists as a separate entity than the nasal cavity. Chemoreceptors detect chemical signals from the organism’s environment and transduce a physiological response accordingly. Studies indicate that nepetalactone (the chemical produced by “catnip”) is responsible for eliciting a psychosexual response in cats by mimicking a sex pheromone and interacting with the feline vomeronasal organ. Although human beings and felines are both mammals, they react to the chemical in “catnip” much differently than one another. “Catnip” elicits no response in human beings and a rather strong response in felines. The distinction between these responses can most likely be attributed to a physiological difference in the feline and human sensory system.
The Vomeronasal Organ in Humans
The function of the vomeronasal organ in human beings is actually quite controversial. Studies on human embryos have indicated that the vomeronasal organ does correspond to the vomeronasal organ in cats and other mammals. Although the vomeronasal organ is common in both feline and human species, the organ in humans was thought by scientist to be vestigial (or no longer functioning). The vestigality of the vomeronasal organ in human beings may explain why humans do not react to chemicals in “catnip” however this is an unlikely explanation because studies have shown human beings can react to pheromones. Another explanation to the differing reactions could potentially be attributed to the physiological differences in the organs themselves (show left).
So Why are Mosquitoes Repelled?
So why are mosquitoes seemingly repelled by some essential oils extracted from different plants and herbs (including “catnip”)? This question is a little more difficult to answer directly because little is known about insect sensory system. Studies have shown that mosquitoes are more attracted to people with high concentrations of steroids and cholesterol on the surface of the skin. Mosquitoes are attracted and repelled by certain pheromones. More than likely, the chemical nepetalactone in “catnip” is able to mimic a pheromone that triggers a chemical signal causing the insect to become repelled (acting as an insecticide).
It is truly amazing that the same chemical can signal different responses in different organisms. The responses to chemical signals in the organism’s environment are evolutionarily beneficial; whether it be to attract a mate or flee from impending danger. According to a news report conducted by NPR the CDC is working on natural repellant consisting of extract from cedar tree. This substance is completely environmentally friendly and actually acts as an insecticide. It is able to kill the mosquitoes by blocking receptors on their nerve cells (absent in human beings). Although the chemical found in ”catnip” is not known to be an insecticide, the similarity between natural extracts (from ”catnip” and cedar tree) may certainly explain insects natural repulsion from them.
Crazy for “Catnip” March 14, 2011Posted by mhostetler099 in Behavior, Biology, Chemistry, Fun, Health, Uncategorized.
add a comment
Nepeta cataria, more commonly known as “Catnip” is a perennial herb that belongs to the mint family. This herb packs a powerful punch to cats by provoking a state of euphoria usually lasting several minutes (video). Many times herbs are utilized for medicinal purposes , but “catnip” obviously doesn’t affect human beings in the same way that it does cats. What is it about “catnip” that provokes a euphoric response in cats but not in human beings?
Studies suggests that the chemical nepetalactone found in “catnip” is primarily responsible for triggering the response in cats. Nepetalactone evokes a psychosexual response in both male and female cats by mimicking a sex pheromone found in cat urine.
Bugs aren’t so crazy for “catnip”
The chemical nepetalactone may attract felines, but does quite the opposite to some insects. Researchers at Iowa State University found that the chemical nepetalactone is a successful repellent of mosquitoes, flies, and cockroaches. Particularly, the research team at Iowa State found that a solution of catnip extract is comparable in effectiveness to a ten times more concentrated solution of DEET. Research in finding alternatives to repellents or pesticides, such as DEET, is very important because chemicals contained in most pesticides pose a serious threat to human health and the environment. Unfortunately, the essential oils in “catnip” are extremely volatile and have a potent, but short lived repelling effect. Further research in reducing its volatility is essential before such repellents can be used by the general public.
Catnip’s properties are multifunctional
Interestingly, researchers at the Max-Planck Society found that birds that used different types herbal plants in their nests produced offspring that were less prone to infestation of mites. This study indicates that other herbs may have the same insect-repelling power as “catnip” and that organisms other than humans are using this characteristic to their benefit.
In the future, the active ingredient, nepetalactone, may be found in the bottle of repellent you spray on yourself or the pesticide you sprinkle on your plants. You can be sure that the product you are using is much safer than the products of old, but if you have cats you must beware! Such products will still provoke the same euphoric response caused by “catnip” sold in pet stores.
Cramming: A Student’s Best Friend? March 4, 2011Posted by ljsteele in Behavior, Biology, Chemistry, Health, Medicine, Science & Culture, Uncategorized.
The night flies by…
As a senior undergraduate student, slowly over the past four years I have realized the importance of cramming before a test. Simply put, by this stage in my academic career, it has become routine to stay up all night before a test to study. In classes where there are multiple choice tests, it appears to be easier to stay up all night cramming, as is the belief that if you at least can recognize the question, ruling out the different choices for the answer becomes quite simple. It has been shown that over a third of students cram the night before a test.
However, although many students utilize the practice of cramming, whether or not it helps students is up for debate. There are different levels of cramming, and each appear to cause different results when it comes to grades and GPA. The issue that is starting to be seen is that although cramming may help in terms of short term memory, the retention of that information weeks after the course ends seems to be up in the air. Of course, when cramming is being utilized, it only makes sense that the information storage would be contained in the frontal lobe of the brain, while long term memory, which would be associated with studying that has taken place over numerous days or weeks, would be stored over multiple parts of the brain.
Many different universities have brought to light the health implications that one may bring upon him or herself when cramming. But, it is also shown that certain periods of acute stress are positive for the human body, which cramming would appear to fall under the category of acute stress. During acute stress, the body increases its fight or flight response (epinephrine and norepinephrine), shuts down digestion, reproductive systems, and boosts metabolism. Vasoconstriction and vasodilation also take place, therefore pumping blood into certain areas of the body and brain that during a normal day’s activities may not get stimulated very often. Especially during the fight or flight response, one becomes more attentive, which would seem to help with say, studying for a huge test.
Are there more effects than just retaining information?
Although cramming may not be ideal for certain people, research needs to continue in terms of stress and cramming, and even learning styles. Certain people are exposed to more stress than others, so possibly stress levels are compromised, leading to a decreased ability to study and cram the night before a test. Students continue to cram because results are obtained on tests and finals. Quite possibly cramming could do more than just get a student a good grade on a test-it could also help to train the body for different stress activities that otherwise may not be achieved.
Stress and the GI Tract December 17, 2010Posted by ljsteele in Behavior, Biology, Chemistry, Ecology, Environment/Conservation, Health, Neuroscience.
add a comment
The mechanics of stress and the gut.
Stress is shown to have a huge effect on the body, whether or not it is experienced as an acute or chronic stress. A major topic of interest is what effects stress has on the gastrointestinal tract in organisms. According to a multi-part scientific paper entitled “Stress and the Gastrointestinal Tract”, there are many different stressors that can be examined within a variety of organisms. Examples of the stressors explored include food deprivation, fearful sounds, weather changes, and water avoidance ( an acute stressors explored in lab organisms such as mice, rats, and guinea pigs). It has also been shown that acute stressors in humans, such as pain exposure, anger, fear, and intense exercise can cause gastrointestinal shut down.
From the stressors listed above, research has explored how stress influences gastro muscles to slow contraction, thus inhibiting the processing of food. An interesting reaction to this slowing of peristaltic movement is the fact that many organisms lose control of their colon, showing defecation in response to certain stimuli such as fear and water avoidance. Corticotropin releasing hormone, also known as CRH (or CRF, as identified in the aforementioned paper), is released from the hypothalamus, and blocks the effects of the vagas nerve, while also traveling through the solar plexus, and attaching to receptors in the stomach.
Once bound, this hormone has been shown to inhibit gastro movement, and thus preventing emptying of the stomach. The difference between the stomach and the colon is that the stomach requires contraction of the muscles to push food through, whereas the colon requires contraction to keep bowel movements inside the body. With the effect of CRH binding to the receptors, relaxation in gastrointestinal muscles occur, which is why the release of the colon sphincter results. However, the results explored here were in response to short term stressors. The effects of long-term stressors have yet to be studied.
Stress and Ulcers
What does this research mean to you? Well, the results we glean from research like this offer powerful implications for human medicine and today’s society. Many people not only experience acute stress, but chronic stress as well. Short term affects of acute stress include accelerated of heartbeat and an increase in metabolism, but it is only natural to ponder the long term effects of chronic stress. We can extrapolate from the results of acute stress that it would make sense that we, as humans, would not want these effects to be long lasting. Major problems would arise with the decrease of gastro movement. Problems manifest from a build up of bile and stomach acids in the stomach. Since gut motility is decreased when stressed, less movement would mean that more bile, which is highly acidic, would sit in the stomach longer and could lead to stomach or intestinal ulcers.
Chronic stress can also lead to a decrease in the immune system of the organism as well as a decrease in the second messenger systems within the body. An example of this effect on a second messenger system is the attachment of CRH to CRH-receptors in the solar plexus. The binding of these receptors causes the effect of the decrease in gastro movement.
How much stress is too much stress?
Lastly, with chronic stress and chronic stimulation of the CRH/CRF system, we might see a scenario in that the more that these receptors are activated, the more desensatized they can become. This could cause problems for people and their response to stress. If the are “desensitized” this may mean that these people have a problem when trying to properly responding to an acute stressors when needed.
Dang My Appetite! December 8, 2010Posted by wframe488 in Behavior, Biology, Health, Medicine, Nutrition, Physiology.
add a comment
It wasn’t until recently America realized just how overweight people were getting in our country. I believe we are one of the most overweight countries of the world if I am not mistaken. It seems like new diet plans, weight-loss pills, and surgeries are developed everyday to help obese Americans shed those pounds. Weight-loss has definitely been growing its popularity, for example new reality television shows like The Biggest Loser , Weighing In, and Celebrity Fit Club, to name a few, have gotten people interested in getting up off the couch and exercising.
The fast food industry and video games can be partially blamed for helping Americans achieve the great honor of being one of the “biggest” countries in the world, but let’s not forget about our genetics. There are several hormones in our endocrine system that plays a role in weight regulation and weight-related behaviors like hunger and satiation. Two of the most popular and most talked about weight regulating hormones would have to be ghrelin and leptin. We all typically produce these hormones, but in different amounts depending on the person. Ghrelin is a preprohormone that is normally produced in the stomach. It is a known appetite inducer and has also been known to slow down metabolism and decrease the body’s ability to burn fat. It stimulates the hypothalamus to release growth hormone via a GSH receptor. Leptin, on the other hand, is known to aid in appetite inhibition. It is expressed predominantly by adipocytes and contains highly expressed receptors in the hypothalamus region of the brain. It stimulates the hypothalamus via an Ob receptor to decrease appetite and body weight.
One research article that I found about this particular topic, by J.P.H. Wilding, was titled “Food Fails to Suppress Ghrelin Levels in Obese Humans”. This research paper investigated the effects of a test meal on the plasma levels of both ghrelin and leptin. They sampled 13 lean and 10 obese subjects and found that the lean subjects exhibited a decrease in both ghrelin and leptin levels after a meal whereas the obese did not show any signs of decrease in concentration of these two hormones. The paper goes on to explain that the role of the decline in leptin of the lean subjects is unknown, but the lack of suppression following a meal of the obese subjects could lead to increased food consumption. This suggests that ghrelin is involved in the pathophysiology of obesity. This appetite inducing hormone is secreted by our bodies with out our control unfortunately and for those that secrete more will mostly likely tend to be bigger human beings just based off of overall caloric intake.
In regards to dieting, one major problem that almost all people possess after they diet is the regain of weight. This mainly is due to the idea that even though your weight is now maintained at a healthy level your appetite still remains the same as it once was, thanks to these two hormones mentioned previously. One interesting article that I read from the Journal of Clinical Endocrinology and Metabolism, was titled, “Appetite Hormones May Predict Weight Regain After Dieting”, which was by Ana B. Crujeiras. Her colleagues and her evaluated a group of 104 overweight men and women during an 8-week low-calorie diet and again 32 weeks after treatment. The scientists measured body weight and plasma ghrelin and leptin levels before, during, and after dieting. What is interesting about this article is that the researchers found that subjects with higher plasma leptin and lower ghrelin levels before dieting were the subjects that were more prone to regaining weight after they shed those pounds through dieting. Personally, I thought that the higher the ghrelin levels prior to dieting would cause the subject to be more prone to weight regain, but that’s not the case here, but that’s science. The article goes on to explain that this can be useful information and that these hormone levels can be proposed as biomarkers for predicting obesity-treatment outcomes.
In conclusion we know that virtually everyone produces ghrelin and leptin in there bodies and that these two hormones play a big role in regulating our appetite. Some of us are lucky enough to sustain the proper balance of these hormones, based solely on our genetics, for body weight maintenance. Although, others aren’t so lucky to possess such a talent. Just because someone is lean and skinny doesn’t mean that they are necessarily healthy, and just because someone totes around more body weight than others doesn’t mean that that person is necessarily unhealthy. In closing, all I have to say is that eating right and exercising is a big part of being healthy and maintaining weight despite what these pesky hormones are doing to our appetite. So, to everyone, eat healthy and exercise!
Don’t Get Tipsy Over Your Hormones October 21, 2010Posted by jfalender232 in Behavior, Biology, Health, Physiology.
add a comment
Okay here’s the scoop, instead of boring you with the likely event that my fellow classmates might have bestowed upon you with their own blog posts, luckily for you, I pledge to make this the most exciting blog post that you will have the opportunity to read (that means you SHOULD click on the words that are highlighted in blue and underlined–you can thank me later for all the joy these links will give you). So enough with the chit-chat for now, let’s get ready to rumbbleeeee!
College is all about experiencing many new things such as moving away from your annoying parent(s), skipping class because it might be raining outside, meeting a myriad of new people, learning the art of mooching off your friends, and finally being exposed to your new best friend but your worst enemy. No I am not talking about Dean Wormer, hopefully you will never have to meet the dean. I am talking about alcohol, booze, liquor. It could make you the most popular person at night but then keep you strapped down to the bed with the worst hangover imaginable (unless you have to deal with Mike Tyson). Please allow me to whet your educational appetite with this nugget of information: “Alcohol dilates the blood vessels, or capillaries, that carry blood just below the surface of the skin. When they expand, the flow of blood to the skin is increased. The skin flushes, causing a warm feeling.” Alright so now that we are all warm and fuzzy inside lets jump in and explore this topic some more.
Alcohol and has many effects on the human body but one of the most important areas of research is the relationship between alcohol and hormones. WedMD defines hormones as “a chemical substance, formed in one organ or part of the body and carried in the blood to another organ or part where they exert functional effects; depending on the specificity of their effects, hormones can alter the functional activity, and sometimes the structure, of just one organ or tissue or various numbers of them.” Furthermore, alcohol has 4 primary areas that can effect: the regulation of blood sugar levels, reproductive functions, calcium metabolism, and bone structure.
Contrary to Def Leppards wish, I don’t want you to pour some sugar on me, so by realizing that your alcohol drinking can affect all three of your glucose sources and the functions of regulatory hormones will go a long way towards having a healthy relationship with your body. “Even in well-nourished people, alcohol can disturb blood sugar levels. Acute alcohol consumption, especially in combination with sugar, augments insulin secretion and causes temporary hypoglycemia. In addition, studies in healthy subjects and insulin-dependent diabetics have shown that acute alcohol consumption can impair the hormonal response to hypoglycemia (*More Info*)”. Maintaining normal blood sugar levels are crucial to the homeostasis of your body.
I would like to take a time-out here and impart some of facts of college life as told by yours truly (WARNING: please take all these facts with a grain of salt): You will spend more time thinking about sex than anything you might learn in a class. That being said, alcohol can have some potentially serious side effects on the reproductive system of both males and females. “In men, reproductive hormones are responsible for sexual maturation, sperm development and thus fertility, and various aspects of male sexual behavior. In women, hormones promote the development of secondary sexual characteristics, such as breast development and distribution of body hair; regulate the menstrual cycle; and are necessary to maintain pregnancy. Chronic heavy drinking can interfere with all these functions. Its most severe consequences in both men and women include inadequate functioning of the testes and ovaries, resulting in hormonal deficiencies, sexual dysfunction, and infertility (*More Info*)”. This is important to keep in mind because for males, extended low levels of testosterone can lead to the developing of feminization of males characteristics such as “breast enlargement”. Women need to be aware of alcohol effects because prolonged drinking can lead to “cessation of menstruation, irregular menstrual cycles, and menstrual cycles without ovulation, early menopause, and increased risk of spontaneous abortions (*More Info*)”. This leads to a creed that all should take to heart: ‘You can always dump your boyfriend or girlfriend, but never ever dump your hormones.’
The final two areas that we are covering in-depth, calcium metabolism and bone structure are closely correlated to one another. Calcium is the main building block of bones and is essential to the cell to cell communication. Speaking of communication relationships, ‘America’s favorite life-guru’ Dr. Phil can answer any communication issues you might have here.
The role of alcohol in calcium and bone metabolism can lead to several complications. “Acute alcohol consumption can lead to a transient parathyroid hormone (PTH) deficiency and increased urinary calcium excretion, resulting in loss of calcium from the body (*More Info*). Chronic heavy drinking can disturb vitamin D metabolism, resulting in inadequate absorption of dietary calcium (*More Info*)”. These decreased calcium levels can potentially lead to bone diseases, most notably, osteoporosis. MedicineNet describes osteoporosis as, “a condition characterized by a decrease in the density of bone, decreasing its strength and resulting in fragile bones. Osteoporosis literally leads to abnormally porous bone that is compressible, like a sponge. This disorder of the skeleton weakens the bone and results in frequent fractures in the bones”. So yes it is possible that if you are not careful, excessive alcohol consumption could lead you to looking like this dashing fellow below.
So the next time you and your friends start to pour shots, shotgun beers, or do keg stands to the greatest 80s song of all time Here I Go Again, just remember that your hormones are relying on you as their designated driver for the night.
Please check out my friend, Wes’ blog, who examines more about alcoholism and its effects on the endocrine. It’s a great read!
The Science of Satiation October 16, 2010Posted by Kyle in Behavior, Biology, Chemistry, Health, Nutrition, Uncategorized.
Slow down or you’ll get a stomach ache!
My parents always told me that if I eat my food really fast, I may feel sick later. I am sure most people have experienced this at least once in their life. It seems that the reason for this is…that the faster you eat, the faster your stomach fills up. Your stomach ends up being full, or over-filled, before your body realizes it. By the time you do feel full, it is too late to stop eating and your stomach may feel like it’s going to explode.
It’s bad enough that your favorite meal can cause you pain after you devour it, but that’s not all it will do. Common sense should tell you that eating too much of something can potentially lead to being overweight. So if you’re eating too fast you can end up doing just that, gaining a lot of weight. An article from the British Medical Journal points out that eating too fast triples the risk of being overweight. Makes perfect sense…more food in equals more pounds put on. But the next question remains: what are the mechanisms behind all of this?
The science of satiation
An article out of The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM) points out that gut hormones my play a part in why people who eat fast end up overeating. As Alexander Kokkinos, MD, PhD, of Laiko General Hospital in Athens, Greece points out, gut hormones that signal the brain to stop eating may be impacted by the rate of eating. The hormones that Kokkinos article examined were peptide YY (PYY) and glucagon-like peptide (GLP-1) which work to signal to us that we are full after a meal. For the study, the researchers took blood samples from participants after they had all eaten the same meal, however, the amount of time each participant took to eat the meal varied. Their results showed that the participants who took longer periods of time to eat the meal had higher levels of the gut hormones and felt more full than those who ate their meals faster. So what does this all mean?
Your body tries its best to tell you stop eating, but if you don’t get the signal in time it doesn’t matter. As many Americans go about their day, they consume a massive amount of calories for very little cost. Going through the drive through doesn’t burn nearly as many calories as chasing down a woolly mammoth. Our early ancestors couldn’t go through the drive through for dinner, they had to work for their meal. Not only that, they probably didn’t eat nearly as much as we do today. Consuming a ton of calories and burning very few makes someone more likely to be overweight, but if you add in the fact that some people are consuming their meals in only a few minutes and eating large portions, these people are at a much higher risk of gaining weight. So next time you sit down for a meal, try and eat slowly. This will give your gut time to tell your brain that it’s time to quit eating. Your gut will be happy, and you may just lose a few pounds in the long run.
Shedding Light on Alcoholism October 15, 2010Posted by wframe488 in Behavior, Biology.
add a comment
Scientists today are investigating the relationships between stress and the over use of alcohol. Alcoholism has been an ongoing problem since the Egyptians discovered wine 10,000 years ago. According to the Department of Psychopharmacology, at the University of Heidelberg, in Germany, alcohol consumption is an essential part of daily life of many different societies. The benefits that come from the production, sale, and use of these alcoholic beverages have been found to be detrimental to these societies. The World Health Organization ranks alcohol as one of the primary causes of disease and health problems in industrialized countries.
Alcoholism is an addictive behavior that arises from molecular physiology, according to Sillaber, “Alcohol-related diseases, especially alcoholism, are the result of cumulative responses to alcohol exposure, the genetic make-up of an individual, and the environmental perturbations over time”. In 2002 Sillaber and his colleagues published a scientific paper titled “Enhanced and Delayed Stress-Induced Alcohol Drinking in Mice Lacking Functional CRH1 Receptors.” With this study they found that there is a relationship between stress and drinking alcohol for the average mouse. They studied corticotropin-releasing hormone (CRH) and how it mediates responses to stress and alcohol intake. What I want to know is why on earth these mice are drinking alcohol? …but anyway, mice that lacked an efficient CRH1 receptor underwent progressive alcohol intake. With repeated stress added to the mice this particular drinking behavior persisted throughout their life. They discovered that this behavior was associated with the up-regulation of N-methyl-D-aspartate receptor (NMDA) subunit (NR2B). So, alterations of the CRH1 receptor and changes in NR2B subunits could compose a genetic risk factor for alcoholism.
Cortisol is a steroid hormone or glucocorticoid produced by the adrenal gland. It is released in response to stress, and low levels of blood glucocorticoids. Its primary functions are to increase blood sugar through gluconeogenesis, suppress the immune system, and aid in fat, protein, and carbohydrate metabolism. The secretion of corticotropin-releasing hormone (CRH) by the hypothalamus triggers pituitary secretion of adrenal corticotrophic hormone (ACTH); ACTH is carried by the blood to the adrenal cortex where it triggers glucocorticoid secretion. It’s a long and confusing process but in the end cortisol should be released. In the study by Sillaber the CRH1 receptors of the mice were ineffective which meant that the pituitary gland was not being stimulated to produce the glucocorticoid, cortisol, to deal with the stressful environment. This then lead to excessive alcohol consumption by the mice. This idea sheds light on a possible influence in humans.
Let’s face it we are all stressed at one point or another and we all have different ways of dealing with this stress. Some go fishing, others listen to music, or exercise, but some of us drink alcohol… and lots of it. According to the results of the Sillaber study it is possible that CRH deficiency could be a factor in human alcoholism. Check out the blog by my friend Joe for additional information.
Urban ecology…right here on campus! May 28, 2010Posted by Dr. O in Behavior, Biology, Ecology, Environment/Conservation.
add a comment
So this is our resident, young, red-tailed hawk…
(Please click on pictures for better resolution)
This young red-tailed hawk enjoys a very urban lifestyle on Marian University’s campus. I have watched this bird pick off fat, almost tame, squirrels as they exit a garbage can with the crust of a Subway sandwich. The hawk will narrowly, but deftly, miss flying into people’s heads as it goes in for the kill.
Today I arrived on campus, pulled into my parking spot, opened the door, and heard a ruckus of robins.
When I looked, I saw said hawk and thought, “hmm…guess the robins don’t like it roosting there”, but then when I looked closer, I realized that the hawk was IN THEIR NEST! As my jaw dropped the hawk took off with two fistfuls of nestling robins. The hawk flew to the nearest tree (where it perches above previously mentioned garbage can/squirrel haunt) and picked apart its breakfast. Amazing!
Red-tailed hawks don’t eat birds (usually), not small birds.
The hawk must’ve been watching and knew where this nest was. It’s not like it went after a fledgling not able to fly…it went INTO the nest to grab them! And the nest was fairly hidden! I think this is incredible urban behavior in a predator; not afraid of people, and exploring novel food items.
Here are two videos of the hawk eating the nestlings and of the adult robins guarding their, now empty, nest:
Here is a collection of play-by-play photos of the event:
Penguins, endangered? May 3, 2010Posted by Kyle in Behavior, Biology, Climate Change, Ecology, Environment/Conservation, Evolution, Fun.
1 comment so far
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.)