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Sep082009
POSTED AT 07:14 PM
I really love science. I'm not sure why, because nothing in my childhood made me particularly interested in it. My mom was a school librarian, so it's not like we were out dredging ponds and hunting under rocks all the time. However, for as long as I can remember, I have been fascinated by living things; I do love looking in ponds and turning over rocks and rotting logs. I love to discover things; to explore, to experiment, and to figure things out. Perhaps it's a personality trait, or perhaps there was something that I did when I was a child that planted a seed in my mind.
One reason that I love science is because I think that the world around us is amazing! We have glow-in-the-dark jellyfish, trees that live to be thousands of years old, there were dinosaurs here in Massachusetts! Everything is made of chemicals, and the interaction of these chemicals result in the air we breathe, the food we eat, and our own bodies! I find it amazing that we can describe the motion of objects around us using mathematical formulas, and that energy transfers allow for all of that motion. Just about everything and anything can be connected to science, including the shape of a person's nose, the swimming behavior of guppies, the pollution produced by our cars, the change of season, and the distinctive behavior of adolescents!
Now, I know that not all of you love science, and that is okay...for now. One of my goals is to help foster a love of science in at least a few more of you. What I'd like for you to do right now is to tell me a little bit about how YOU feel about science. Your answer should be three to five sentences long. Please be honest!
Apr172009
POSTED AT 01:16 PM
I have to add this entry about a red fox (Vulpes vulpes) and her four kits that I have been watching near my house. Right down the street from me, there is a large farm field--they usually just grow hay there, but it is currently cut short. In the middle of the field there is an area of bare earth with a bit of loose dirt on it. Last week we saw a mother fox and her four kits come out of the hole. The mother came out first and looked around. She then made a noise and her babies came tumbling out! The four kits wrestled and chased each other and the mother sat about twenty feet away from them, keeping watch. Another day, we saw her bring them what looked like a dead chicken!
The photo below shows the mother fox and her babies, called kits.
I looked up foxes in Massachusetts and found out that there are two species of foxes in Massachusetts; the red fox (Vulpes vulpes) and the gray fox ( Urocyon cinereoargenteus) ( http://www.mass.gov/dfwele/dfw/wildlife/living/living_with_foxes.htm). Both species are common in our state, but, although I have seen many red foxes, I have never seen a gray fox. This was the first time that I saw baby foxes, or kits.
Red foxes breed in late January to February, and they use a den that is a hole dug in the earth. The entire hole, which often is a hole dug by a different animal like a woodchuck and enlarged by the fox, can be 15 to 20 feet long. A litter of four kits like I saw is the most common, and the babies are ready to be independent by the next fall.
One thing that I found curious was that the foxes were living practically in someone's backyard, and close enough to a road that we could see them. However, the website says that foxes often raid people's garbage, so it would make sense that they would live close to humans. Although foxes, like bats, skunks, and raccoons, can carry rabies, I found some of the suggestions on this website to be a bit ridiculous! For example, it says, "Don't let foxes intimidate you! Don't hesitate to scare or threaten foxes with loud noises, bright lights, or water." They only weigh from six to fifteen pounds! I thought that the mother fox and her babies were beautiful.
Update May, 2009: Apparently there are actually SIX kits! Here is a more recent picture of two of them:
Mar292009
POSTED AT 06:11 PM
My son had a cold last week, and though he is better, now I have it. I used a search engine to look for information on what causes cold symptoms, and I found a plethora of interesting news articles about the common cold on Science Daily. From reading these articles, I learned that the common cold is most frequently caused by varieties of Rhinovirus, and that there are more than 100 different strains. Rhinoviruses mutate frequently so that our immune systems do not recongize them. Once we have had a particular strain of the virus, our immune system is armed and ready the next time, and can destroy the viruses before we get sick. If the virus is slightly different due to a mutation, then our immune system does not get ready as quickly. One surprising thing that I learned is that what we think of as a cold is caused by several different types of viruses, including coronavirus, influenza A virus and respiratory syncitial virus (RSV).
  The real Rhinovirus (left) isn't as cute as the plush one!
Another thing that I learned about the common cold is that the cold symptoms that we get--the sneezing, watery eyes, stuffy nose, aches, and exhaustion--are not caused directly by the cold virus. Instead, they are caused by our bodies' own reaction to the virus. Our immune system releases chemicals called inflammatory mediators, which help fight infections through various actions, including blood vessel dilation, mucus secretion, and sneezing. The aches and pains associated with a cold are also caused by these chemical warriors.
Well, why did I get a cold? Apparently, cold viruses live longer in cold, dry conditions, so the winter months in Massachusetts are ideal conditions for cold viruses. When someone with a cold sneezes, the cold viruses are carried in the droplets of moisture that fly from the person's mouth and nose (gross). The dry air removes the moisture, and apparently cold viruses like to be dry. The virus lives longer in this condition, and can be transferred more easily.
 A sneeze! Finally, how can I get rid of this cold faster? Antibiotics do not work on viruses; they only help with bacterial infections such as strep throat. However, it turns out that there are some things that I can do. One of the Science Daily articles says that a study has found that drinking hot drinks such as a fruit cordial helps to get rid of a cold. They compared the results for subjects with colds who drank cold and hot drinks and found that the ones that drank the hot beverages had a relief of their symptoms. A separate article listed some home remedies that studies have found to be effective; many have been around for hundreds of years. These home remedies include garlic, thyme, cayenne pepper, lemon balm, eucalyptus, honey and lemon, and fruit juices.
I have one question remaining: What's fruit cordial? I looked it up, and apparently it's fruit juice, so I'm going to heat up some juice and give it a try!
Feb262009
POSTED AT 01:40 PM
On Wednesday of February vacation week, I was driving down Harwood Avenue at about 4:45 pm. As I was driving over the part of the road that divides part of Mill Pond, I noticed the shape of an animal sitting on the ice to my right. I recognized the long body and tail of an otter, and was so excited that I turned around and parked to watch the animal. The otter was sitting near a large area of open water, and when I stopped to watch it, it jumped into the water. I stayed for about fifteen minutes, and while I was there, the otter would dive down for about thirty seconds and then poke its head up and shake it. It seemed to be eating something. It also seemed to look directly at me a few times, as if it knew I was watching!
I have seen otters in zoos and aquariums before, but this was the first time I had seen one in the wild! I wondered why it was alone, and how it survives in the cold, icy water. I wondered why I had never seen one before.
To find out more about otters, I looked up "otter" on the Internet. I found out that there are thirteen different species of otter, including the giant river otter of South America, which can be up to six feet long! The scientific name of the American river otter is Lutra canadensis, and it's in the weasel family. It's closest relatives are weasels like minks and fisher cats, polecats (where do they live?) and badgers. For you evolution enthusiasts, otters have been around since the Pleistocene.
Otters eat fish, shellfish, other invertebrates, amphibians, birds and small mammals! I always just assumed that they ate fish, but I guess they eat more than that! Apparently they have a really fast metabolism, which means that they burn off their food really fast. This explains how they can keep warm in the icy water, and it means that they have to eat a lot.
Incidentally, I also saw a bobcat in Littleton in December!
(below) American river otters (Lutra canadensis)
Aren't they adorable?
Jan292009
POSTED AT 09:42 PM
The other day in class, I was explaining how the photogates for the physics equipment work. They use infrared light, which is light that is just outside of the wavelengths of light that human eyes can see. The electromagnetic spectrum below shows all the different types of electromagnetic energy, or light, in the universe.
Visible light, or the light that we can see, is in the center of the spectrum. Human eyes can see light with wavelengths from 400 to 700 nanometers. Infrared is just to the left. It is light that has wavelengths a bit longer than 700 nm. All objects give off infrared radiation; the hotter the object, the more infrared is given off. Some organisms, like pit vipers, boa constrictors, and some insects, can see infrared. We have developed ways to make infrared visible, with special cameras and film.
 This photo shows the infrared radiation emitted by a dog.
The sun emits all the radiation in the spectrum. The atmosphere, including the ozone layer, prevents much of the radiation from reaching the surface of the earth. Nonetheless, we are daily bombarded with X-, gamma, radio, ultraviolet, and microwaves. Although we cannot see them, we can detect their presence. One detector that we all carry with us is our skin, which tans, freckles or burns (depending on our genetic makeup) in response to exposure to ultraviolet radiation.
This got me started thinking about how there is so much around us that we cannot see. It is amazing that there is an entire universe that exists outside of our range of vision! For example, a drop of pond water may at first glance look similar to a drop of tap water. However, it contains tiny one-celled creatures that go through their lifespans unobserved by us. Even smaller than these creatures are bacteria and viruses. Of course, everything around us, including these bacteria and viruses, are made of molecules, built of atoms bonded together in particular patterns to make all known matter. If this isn't mind-boggling enough, they tell us that atoms themselves are made of even smaller particles; electrons, protons, neutrons, quarks, gluons and neutrinos! The electricity that powers the laptop that I am using is created from the kinetic (moving) energy of electrons!
Nov252008
POSTED AT 05:39 PM
As I roamed through several science news websites, I found so many cool articles that I had a difficult time choosing one. I decided to "focus" on three that are good connections to our current science study as we move from genetics into evolution.(One that I ended up not using is about face shields for football helmets--go to http://www.sciencedaily.com/releases/2008/11/081117193017.htm )
I read one article on the sequencing of the woolly mammoth genome. The genome of a species is the entire DNA sequence of a particular species of animals, and is very useful for determining which species are most closely related and how long ago they shared a common ancestor. The scientists that managed to sequence the woolly mammoth genome found that they are most closely related to African elephants, and that they last shared an ancestor around 6 million years ago. There were possibly two species of woolly mammoths in Siberia, although there is a disagreement between the two sets of researchers.
 Incidentallly, I read a book once about a hypothesis that many of the monsters from ancient Greek and Roman myths are based on dinosaur and woolly mammoth bones that they found. The Cyclops may have been based on woolly mammoth bones. Archaelogists have found burial sites with mammoth bones arranged in a human form. The hole in the mammoth skull where the trunk was could have been the Cyclops' single eye.
The second article is called "Sequencing the Dead to Save the Living," and is about why scientists think it is helpful to sequence the DNA of organisms that lived a long time ago. They use the sequencing of the woolly mammoth genome and the genome of the Neandertal hominids as examples. By gaining knowledge about the genes of these long-lost species, we can start to figure how they are related to modern animals, what genetic vulnerabilities may have caused their extinction, and perhaps how we can help endangered species today. For example, scientists are comparing the DNA of Neandertals, humans, and apes to figure out how the three groups are related. They do not believe that Neandertals are related to us directly, and that the
ancestors of modern humans therefore did not interbreed with them. By comparing the genomes of Neandertals with Homo sapiens, scientists may be able to figure out what allowed our ancestors to outcompete them and survive to modern times.
The last article that I read described the role that bacteria may play in fossilization of soft-bodied animals like jellyfish and sea cucumbers or the soft parts of vertebrates. These types of fossils are very rare because usually the soft parts decompose quickly. However, if the dead animal is quickly buried in the mud on the ocean floor, anerobic bacteria (bacteria that lives without oxygen) take over the cells of the dead animal and reproduce quickly. The bacteria create a type of coating that covers the structure of the organism, preserving the shape. Finally, the bacteria deposit minerals like calcium carbonate that make the fossil literally rock-hard.
Here is a web page with links to all of the sequenced genomes. You can look up the genes of more than 180 organisms!
Okay; this was a long one, but I was late on this entry...I've paid my penance!
Nov082008
POSTED AT 06:45 PM
The earth's surface is made up of crustal plates that float on top of liquid magma in the mantle of the planet. The plates are constantly being formed by liquid magma leaking up out of the sea floor, pushing the new crust away. The other edges of the plates are pushed up against each other, either pushing up to form mountains, or subducting below into the mantle, where the old crust is remelted and joins the liquid magma.
Sometimes the crustal plates rub against one another, creating pressure as they push together. If one suddenly slips and slides loose, this is what we call an earthquake. Imagine if you were pushing hard against your friend, and one of you slipped and fell. Both of you would lose your balance. The slipping of the plates releases a lot of stored-up energy, which reverberates through the surrounding crust. If an earthquake happens in the crust below the ocean, the buckling of the plates can create a tidal wave, which is what happened in Indonesia in 2004.
Last year, we had a small earthquake with an epicenter in Littleton. You may have felt a vibration or heard a loud bang. The reason that we had an earthquake is because we live near a small fault line, where two or more plates meet. Here is a great link on why we have earthquakes in New England:
Here is a picture of the San Andreas Fault in California. Now, that's a fault!
Sep252008
POSTED AT 08:43 PM
I read an article called "Are Bacteria Foes of Diabetes?" in Science Now Daily News at http://sciencenow.sciencemag.org/cgi/content/full/2008/923/4. This article says that researchers have found that it seems that exposure to bacteria may play a part in the development of diabetes.However, rather than causing the disease, it seems that the presence of certain types of bacteria in the pancreas (which makes insulin) actually prevents the disease from starting.
This article reminds me of an NPR science program that I listened to a few weeks ago. In this program, a researcher that was interviewed said that he estimates that 90% of the human body is made up of bacteria! He also said that these bacteria play a key role in regulating many functions of our body systems and in the prevention of diseases. Of course, yogurts with "active cultures" are promoted to improve digestive help, so it does make sense that bacteria would help to regulate other body systems too. I think that this is both absolutely fascinating and kind of hard to believe. How can our bodies be mostly bacteria? I want to know more about this!
Sep012008
POSTED AT 05:25 PM
I read an article about alligators on sciencenewsforkids.org. Scientists have recently discovered that alligators are able to move their lungs up and down to adjust their buoyancy in the water. They have muscles attached to their liver (sounds painful, doesn't it?) and hip bones. When they pull down on the muscles, the lungs get pulled down too. They use these muscles to shift lungs up (to surface), down towards their tail (to dive) and sideways (to help them roll). This reminds me of a cartesian diver, which many of you may have made or played with in earlier science classes.
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The scientists who studied the alligators think that this other use for lungs (other than breathing) evolved to help the animals move quietly and sneakily through the water. This makes sense, because it would create much more of a disturbance in the water when they use their tail to swim. One thing that I think is kind of strange is that scientists are just figuring this out! It just shows that there is still a lot that we have to learn.
Sep012008
POSTED AT 05:03 PM
Last weekend (August 23-25), I went to upstate New York to visit some friends. On the way back, we stopped to look for fossils in a couple of places. One place that we went to was Schoharie, NY; we hadn't been there before. When we got there, this is what we saw:
It looked pretty uninteresting at first, but when we started picking up rocks and looking at them, it turned out that nearly every rock had a fossil! You see, this part of New York was covered by an ocean 420 million years ago, and today's rocks were ocean mud at that time. The fossils that we found included a lot of brachiopods, like this:
Brachiopods are bilaterally symmetrical; molluscs like clams and oysters are not. There are a few modern species of brachiopods, but they used to be much more common.
In addition to brachiopods, we found fossil crinoids, or sea lilies, which are related to echinoderms like starfish, and molluscs like clams. It seemed that every chunk of rock that we picked up was covered in shells and bits of crinoids and coral.
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