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Post #1 - A Pinched Nerve

A couple of weeks ago I injured my knee dancing. My conclusion was that I had just twisted it and the pain would be gone in a couple of days. It did not work out that way. The next day the pain from my knee had spread through the left side of my body, reaching my back, my left arm, and the left side of my neck. It felt like the right side of my brain had failed me and the motion on the left side of my body was limited. Someone told me that I had pinched a certain nerve in my knee and it had affected other parts of my body. The pain did go away after five or six days, but that persons hypothesis (being a LPN) still lingered in my mind. This is what brought me to the topic of my wikipage.
external image pl_nerve.jpg

The nervous system is made up of tiny cells that are similar to a bunch of electrical cords that send and receive information from the brain to the body and vice-versa. There are two different types of nerves, one being the Motor and the other being the Sensory. The Motor nerves transmit information from the brain to the body. These nerves allow movement and fuction of the body. The Sensory nerves transmit information from the body to the brain. This allows sensations such as pain and taste.

So what is a pinched nerve?

A pinched nerve is caused when a nerve is somehow injured by pressure or by compression. This makes it unable to send it's signal properly. Other causes involve bruises, injuries, or swelling. It can also be hereditary and increase a person's chance in having or developing a pinched nerve. There can be a range of symptoms from a pinched nerve, it all depends on where the nerve is located. The most common symptoms are pain, numbness, tingling, or weakness of the muscles on the path of the nerve. If there is weakness of the muscle where the pinched nerve is located then there is a chance that the damage will be permanent to the nerve.

What about a pinched nerve in the knee/leg?

What I've come to find is that the person's hypothesis was right or close to being right. A pinched nerve in the leg is usually caused by a disease, overuse of the leg, and/or any injury or trauma caused to the leg (dance injury). Symptoms of a pinched nerve in the leg are numbness in the affected leg which will make movement difficult, twitches or spasms, tingling sensation, weakness, and a burning sensation. They are very similar to a regular pinched nerve. The one thing that caught my attention was that sometimes the pain in the leg will spread to the foot, the hip, or the abdomen.

After reaserching the nervous system and pinched nerves I've come to this conclusion: nerves are very spectacular for what they are capable of doing. Like all cells they keep the body running smoothly and efficiently, but if something goes wrong and they are injured or pinched those little cells can cause a big problem.

Eck, J.C. (n.d.). Pinched nerve (nerve entrapment or nerve compression). Retrieved from http://www.medicinenet.com/pinched_nerve/article.htm
Dogra, A. (2010). Pinched nerve in leg. Retrieved from http://www.buzzle.com/articles/pinched-nerve-in-leg.html

Post # 2 - Apoptosis ("suicide sac")
external image apoptosis.jpgThe human body is constantly replacing cells, maybe millions at a time. Apoptosis plays an important role in the replacement of cells as it dissolves or breaks down old, necessary, or unwanted cells. Knowing this, if something were to happen and there is little or to much apoptosis, then it can result in serious diseases. Cancer and leukemia are results of not enough apoptosis as the unwanted and dangerous cells are not being killed off. When there is to much apoptosis then it can kill to many cells and cause tissue damage. Stokes and disorders such as Alzheimer are caused by the overkill of cells.

How apoptosis works:

After receiving specific instructions for the cell to start apoptosis, it will go through many changes before the result of death. Special proteins are called to duty as they break down organelles in the cell and the cell begins to shrink. The break down of chromatin will result in condensation and the cell will become a horse-shoe like figure. Macrophages come along and "clean" the inside of the decomposing cell. To make this happen the cell undergoes plasma membrane changes to trigger the macrophages.

Apoptosis can also be known as "programmed cell death" or "cell suicide".

Shiel, W.C. (2003). Definition of apoptosis. Retrieved from http://www.medterms.com/script/main/art.asp?articlekey=11287
*William Shiel is the chief editor of MedicineNet (the author wasn't given)*
Dash, P. (n.d.). Apoptosis. Retrieved from http://www.sgul.ac.uk/depts/immunology/~dash/apoptosis/

Post # 3 (individual) - The Kiwi Bird

When the word "kiwi" is mentioned, people would most likely think of the tart green fruit that can be found at the grocery store. What people don't know is that there is a bird as unique as the fruit that bears the same name.

external image Animals_Birds_Kiwi_bird_026192_.jpg
The main reason people don't know about the kiwi bird is that they are indigenous to New Zealand. They are classified as the smallest of flightless birds and are considered the species of bird closest to mammals. They are the size of a chicken and resemble little furry gray-brown balls of fur. Even though they are equipped with wings, they lack a keel (an extension of the sternum that helps the muscles in the wings) which means that the wings are useless. Unlike the birds we see in our neighborhood, the kiwi bird has to dig burrows with its strong legs for nesting because they cannot fly. This is also why they are only found in New Zealand as they can't migrate. Though they can't fly and have poor eyesight, they have an amazing sense of smell and well developed hearing. Their beaks are one third the length of their body with the nostrils at the end. The long beak and nostrils help them search for food such as worms, insects, crayfish, and frogs.

You can usually find kiwi birds in damp forests, but some tend to live in grasslands. This is where the female kiwis (usually larger then males) lay there eggs. Did you know that the kiwi's eggs are the largest in relation to the body? Also that it's the male's job to sit on the egg and not the female's? There are many interesting facts about kiwi birds because they are a very unique species. Unfortunately they are endangered and might not be here in the future, but if more people know about these wonderful birds then this possibility may be fiction.

Nair, S. (n.d.). Kiwi bird facts. Retrieved from http://www.buzzle.com/articles/kiwi-bird-facts.html

Post # 4 (individual) - The Starchild

external image images?q=tbn:ANd9GcRBHhylMfjCk2hYh03hhGb9hK4cEX7PfA6bkpbtOsHbEFR_YIeX

During the 1930's, a teenage girl living about 100 miles south-west of Chihuahua, Mexico was exploring the lands when she ended up in a mine tunnel. There she found a skeleton laying on its back, face up with another skeleton hand coming up from a grave next to it. She dug up the grave and found another skeleton, but this one was visibly different. The second skeleton was significantly smaller than the first and it was very misshapen. Deciding to keep the skeletons she placed them in a basket and, on the way home, she hid them under a partly uprooted tree. The next three days there was a missive rain storm. The girl came back to find the bones but because of the water current they had been washed away. Luckily she later found the two skulls caught in some brush.

Years went by and the skulls where passed from one person to another and we eventually picked up by Lloyd Pye, the author of "Everything You Know Is Wrong" which concerns human origins. Interested by the deformity of the second skull, Pye began a research team and started "The Starchild Project". They discovered that the skull was around 900 years old and very different from one of a human. They also spent time on known deformities within the human race and were able to rule them out.

Some unique characteristics about the Starchild skull:
  • The thickness of the bone is around half (sometimes less) of the thickness of a human skull.
  • A human bone has high calcium and phosphorus levels and low oxygen and carbon levels while the Starchild has high carbon and oxygen levels and low phosphorus levels (the calcium stays the same) This means that it is more similar to tooth enamel then bone.
  • There are very strong fiber-like substances embedded in the bone of the skull
  • It doesn't have frontal sinuses
  • It has smaller chewing muscles
  • It's neck attaches on to the front of the skulls frame (this means that its neck is supposedly half the size of a humans)
  • When animals die, bacteria from the body clean out the bone leaving no marrow behind. With the Starchild there was red residue left sprinkled in the bone.

external image skull_sc2.jpgA geneticist contacted Pye to study and test the Starchild skull and found some very interesting and unusual results. It was concluded that 265 base pairs long from the DNA was in fact human. What took them by surprise was that 342 base pairs long of DNA from the skull came out as "no significant similarity found".

What "The Starchild Project" concluded from all these results was that the skull came from an alien born from a human mother. This is what they believed happened:

Two aliens formed a zygote and taking an egg from a human female, they removed its chromosomal package and implanted their zygote into the egg and then the human will give birth to their child.

This was the hardest part for me to believe throughout my research. Why would they do that and how could it happen 900 years ago? I know this is the first time scientists have ever seen this, and I know people are entitled to their own opinion, but is this one even worth taking into consideration? I thought the end product was a little drastic, but the topic itself is very interesting and puzzling.

Pye, L. (Producer). (2010). Starchild skull 2010 DNA result [Web]. Available from http://www.starchildproject.com/

Post #5 (individual) - A Carnivorous Plant

We know plants to be harmless flowers, ferns, and trees that clean our environments using the chemical process know as photosynthesis. This process reacts carbon dioxide and water to produce glucose for the plant and oxygen that is released into the air. A plant can't only survive on this glucose, though, and it needs other nutrients such as nitrogen and calcium to make amino acids and other cell necessities. So what happens when the soil is acidic and needed nutrients can't be found? Most plants can't survive this condition, but a number of plants have a secret weapon to survival.

The Dionaea muscipula, or Venus Flytrap, has mastered the intake of nutrients not only through photosynthesis, but by also consuming insects and spiders. It can be found in a small 700-mile region along the coast of North and South Carolina. In this region they are found growing in humid and sunny wetlands and bogs. Actually, because their living space is so small, the Venus Flytrap was doubted to exist by early botanists.
external image venus-fly-trap-cluster.jpg
So how does this plant work?
All the steps of attracting the insect to digestion are achieved through simple mechanical and chemical processes:
  • Whether the plants wants to eat the insect or not, most of them have some way of attracting insects or animals. For the Venus Flytrap, the two leaves that actually form the trap produce a sweet nectar to draw in an insect or spider as they search for food.

  • The trap is equipped with six short, stiff hairs that grow on the surface of the leaves. These hairs are called trigger hairs.
  • If an insect or spider touches two hairs one after the other, or the same hair is touched twice the trap will close on the prey within half of a second. No one really knows how this happens, but scientists have come up with several hypotheses that include: tension in the plant, ATP-driven changes in water pressure, and pressure and relaxation.
  • It is possible that inedible objects like stones, twigs, and leaves fall into the trap, but the Venus Flytrap has a way of recognizing what is what. This brings us back to the trigger hairs and how the trap uses them. The leaves will close if two hairs are triggered, but they do not close all the way. If an insect or spider is enclosed in the leaves then it will continue to struggle and trigger even more hairs. This lets the trap know to close all the way and start digesting. If a twig or leaf is enclosed in the leaves then it will not struggle which will result in no other triggers. This is when the plant knows not to eat what has landed in it's mouth. It is still a disadvantage, though, to close on an inedible object as it takes 12 hours to reopen the trap.
external image venus-flytrap3.jpg
  • Once the plant is fully closed on an insect or spider it forms an airtight seal. This is the job of the teeth-like cilia so digestive fluids and insect parts can't get out and bacteria and mold can't get in.
  • The trap acts as a stomach as it dissolves the tissues and cell membranes of the prey; kills small amounts of bacteria from the prey; and digests DNA, amino acids, and other cellular molecules that the plant can take in.
  • This continues until all that's left is the exoskeleton and then the Venus Flytrap reabsorbs the digestive fluid.

After one trap has gone trough this process 10 or 12 it loses its ability to close its leaves. The trap continues photosynthesis until about two or three months and then it dies.

Meeker-O'Connell, A. (n.d.). How venus flytraps work. How Stuff Works , Retrieved from http://science.howstuffworks.com/environmental/life/botany/venus-flytrap.htm

Post #6 (individual) - All Dragons Fly

Although they do not resemble our childhood images of dragons, dragonflies still have the colors and hunting techniques that we see in the bad guy guarding the princess in the fairy tale.

They like to live in warm temperatures near swamps and streams as they lay their eggs in water. Dragonflies spend most of their life in water as nymphs and then after one to three years (depending on the species) they emerge from the water. In doing so, they shed a protective layer made of chitin and unfold their wings they take off to the air. Once the cold breeze of autumn hits the adult dragonflies will die, but they have lived long enough to mature and mate with another one of their kind. In fact, after mating the male dragonfly will stay with the female to make sure no other males try to mate with her. How sweet :)

There are a wide variety of colors for dragonflies. Most of them are very vibrant and stand out due to the darker undertone of their bodies:
external image dragonfly.jpgexternal image Why+the+humble+dragonfly+can+help+curb+dengue.jpgexternal image dragonfly-macro-color-twig-insect.jpegexternal image dragonfly.jpg

The dragon's hunting style:

Since dragonflies have a wingspan of 5cm to 18cm and two sets of wings, they can fly forwards, backwards, and sideways. This makes it easier for them to hunt and catch their pray (usually other small insects such as gnats and mosquitoes). They catch their pray by grabbing it with their six legs and using their strong jaws to crush and kill it. Now they can eat the contents of the pray and then drop the dead body once it is sucked dry.

Byrne, C. (n.d.). Dragonfly. Retrieved from http://animals.howstuffworks.com/insects/dragonfly-info.htm
Insect information, facts, and types: what are dragonflies?. (n.d.). Retrieved from http://www.essortment.com/insect-information-types-dragonflies-61773.html

Post #7 (individual) - The Little Mermaidexternal image Ariel%20(3).gif

Sirenomelia (more commonly know as the mermaid syndrome) is a rare birth defect involving the fusion of the legs into a single limb. The syndrome and the defects that come with it are caused by abnormal umbilical cord blood vessels when the baby is growing in the womb. A normal fetus develops with two umbilical arteries and one umbilical vein. They circulate the blood in between the fetus and the placenta. A baby with sirenomelia will only have one umbilical artery and one vein, or two umbilical arteries with one blocked. There are many complications with this including the absence of the arteries that supply the kidneys, large intestine, and the genitalia. Also, the single umbilical artery ends up stealing blood and nutrition from the lower half of the body and brings it to the placenta. Due to the lack of blood and nutrition, the legs cannot form and the kidneys, large intestines, and genitalia are either missing or malformed.

external image mermaid_syndrome.jpgIt is believed that sirenomelia appears once in every 60 000 births and more commonly occurs with twin pregnancies. The mermaid syndrome can be detected in between week 13 to week 26 of a pregnancy with an ultrasound. If the baby is born alive then operations and surgeries are almost always needed to keep them living. This is not common, though, as 50% of babies with sirenomelia are stillborn and the other 50% only live for a few minutes to a few days. There have only been a handful of cases know where the baby actually survived longer than a few days. One of these cases could be found in the United States. Her name was Shiloh Pepin and she was know as the Mermaid Girl.

Shiloh was born in 1999 with sirenomelia and even though she didn't undergo surgery, Shiloh still beat the odds and survived for almost 10 years. She was even featured on Oprah for defying the odds and expectations. Unfortunately on October 23rd, 2009 Shiloh passed away at Main Medical Center.

Colby, R. S. . (2005). Sirenomelia. Retrieved from http://www.healthline.com/galecontent/sirenomelia-1/2
Kita, K. (2009). Sirenomelia much more than a cosmetic defect - mermaid girl dies at age 10. Retrieved from http://plasticsurgery.about.com/b/2009/10/29/sirenomelia-much-more-than-a-cosmetic-defect-mermaid-girl-dies-at-age-10.htm

Post #8 (individual) - I Spy With My Little Eye...

You may think you are crazy when you can see something in front of you that other people can't. It may be floating along or flashing to catch your attention, but for some reason the people around you can't see it. Don't be alarmed, this is normal and can happen to anyone. There is nothing wrong with your vision and you are not seeing things. Well you are, but these specks are not physically in front of you, they are inside you.

First of all, we need to understand the eye. Here is a nice picture for you:

external image eye_diagram.gif

external image Floaters.pngWhen you are younger and your eye is developing, the vitreous is more of a gel-like substance attached to your retina. As we grow older the gel starts to dissolve and it becomes more liquid as it moves to the center of your eye. Some particles, which are called floaters, do not dissolve and continue to "float" around in your eye. We can usually experience these floaters when we are looking at something that has a light background (such as a clear sky or a white computer screen), but we are not actually seeing them. When light enters the eye it passes through the cornea and eventually reaches the retina. The floaters are situated in between the two and sometimes get in the way of light. This is when they will cast a shadow on the retina and affect our vision. When this occurs it's like we can see them physically floating in the air, but we are actually seeing their shadow inside our eye.

Floaters are very common and usually harmless, but sometimes they can be a threat to your vision. In some cases the gel-like vitreous stays attached to part of the retina instead of liquefying. When the vitreous tries to separate from the retina it can cause tears which can develop into a retinal detachment. A tear in the retina can detected by a flood of floaters shadowing the light in the eye. This should get looked at right away.

Haddrill, M. (2010). Eye floaters, flashes and spots. Retrieved from http://www.allaboutvision.com/conditions/spotsfloats.htm
Floaters and flashing lights. (2007). Retrieved from http://www.eyesite.ca/english/public-information/eye-conditions/pdfs/Floaters_e.pdf

Post #9 (individual) - A White Skeleton

external image MultiSoftCoralsVert3-15-15-406x4.jpgClimate change is a major topic that is talked about around the world. Ideas and solutions have been made to reduce the factors that cause climate change such as hybrid cars and energy smart light bulbs. Even with these adjustments, though, the world is still suffering from the dramatic change in temperature. One organism that is being hit hard by climate change would be coral and their reefs.

Corals are apart of the phylum Cnidaria and the class Anthozoa. They live their adult life as sessile polyps that secrete a skeleton of calcium carbonate or limestone. Naturally, this coral skeleton is a white color, but this is not what we see when a coral is healthy and in normal conditions. Coral have a symbiotic relationship with a certain protist called zooxanthellae algae that live in their soft tissues. These algae are what produce the beautiful colors of a coral reef.

Zooxanthellae are photoautotrophs that produce energy through photosynthesis. The coral feeds from the products of the algae's photosynthesis and in return the coral provides protection, shelter, and a constant supply of nitrogen, phosphorus, and carbon dioxide to complete the cycle of photosynthesis. With this relationship, the corals are ultimately in control. They have the ability to get rid of (or expel) these algae at any time. This process is called coral bleaching.

Stress is a major factor with corals. When something causes them to reach an uneasy state then they will expel more algae than needed. This causes them to lose their color and become white or clear. Some stress factors from climate change include:external image ea1663b7064219098ad735fdd3cc249e.png
  • Change in temperature
  • Change in saltiness
  • Change in light levels
  • Pollution
  • Increase in u.v. exposure
  • Change in ocean currents

There is however, a coral reef that is predicted to last longer than the others. There is a reef off the coast of Madagascar that is still thriving and shows hardly any sings of coral bleaching. This is because the reef receives a cool current from the Southern Indian Ocean which keeps the temperature normal as climate change heats up the water.

Hauter, S., & Hauter, D. (n.d.). Coral bleaching. Retrieved from http://saltaquarium.about.com/od/aboutcoraldiseases/a/aacoralbleach.htm
Trivedi, B. (2002). Coral trove found off madagascar. Retrieved from http://news.nationalgeographic.com/news/2002/05/0515_020515_0515TVmadagascar.html

Post #10 (individual) - Scratch, Scratch, Scratch....ahhhhh
Everyone has experienced it many times in their life. When we are just minding our own business we suddenly feel a sensation somewhere in between tickling and paining. Our automatic response is to take our fingers and use are fingernails to relieve ourselves from the irritation. It isn't pleasant when skin develops and itching sensation. So why does it itch then? Well, there are many answers to that. Lets look at a few:

  • If the skin hasn't had a change in appearance then it is probably itchy because of dry skin. It is common for people that live in places with environmental changes. Hot and cold weather with low humidity levels have an effect on skin as well as long term use of central heating or air conditioning. Dry skin can also be the result of washing the body to much.

  • Along with dry skin, allergies and irritation are main causes of itchy skin. Products such as wools and soaps can cause irritation and itchy skin. Even plants like ivy have a side effect of itchiness. Unlike products, allergies are dependent on the person and what they are allergic to (this could include food allergies).
external image itchy+skin.jpg

  • If the skin has an obvious change in appearance then it is probably itchy because of skin conditions or rashes. Chickenpox, lice, scabies, and hives are a few cases that will cause your skin to itch. Usually the itching sensation will be accompanied with redness, bumps, or blisters.

  • If the skin hasn't changed but the itchiness is felt all over the body then it becomes more serious. Internal diseases usually cause this and some of them are fatal. A few of these diseases include kidney failure, liver disease, thyroid problems, and cancers such as leukemia. Nerve disorders can also cause itching. Examples of this would be shingles and MS.

  • Woman develop itchy skin when they are pregnant. The sensation is typically found on the abdomen, breasts, thighs, and arms. This is caused by the stretching of the skin and the hormone changes a woman undergoes during pregnancy. The soles of their feet and the palms of their hands may also itch because of the increase in estrogen (primary female sex hormone).

The skin is a very important organ of the body. Itching it is an automatic response, but when it itches it is sending us a message that could range from "I'm to dry" to "you have an internal disease".
ReferencesHarms, R. W. (2009). Itchy skin (pruritus). Retrieved from http://www.mayoclinic.com/health/itchy-skin/DS00847/DSECTION=causesNewcombe, R. (2010). Itchy skin during pregnancy. Retrieved from http://www.babyandpregnancy.co.uk/ItchySkinPregnant.html

Post #11 - The Aves of Micheal Jackson
Many species have very interesting mating habits. One male species in particular is know to attract it's mate though dance. Every one is familiar with Micheal Jackson's famous move the "moonwalk" where his feet seem to be floating on air as he moves backwards. People must wonder where he got the move from....
external image bird3manakin.jpg

The Pipra mentalis, or Manakin birds, are found living in South and Central America. They tend to stay in forest or woodland areas and the majority of these birds like tropical canopy or dry forests. They feed mostly on fruit in mid flight, but do eat the occasional insect. They are also very social with the same species, but these interactions are very fast and difficult to see with the human eye.
Manakins are very unique when it comes to communication. They are able to produce snaps, buzzes and hums to communicate with each other and to ward off predators. The interesting thing about this is that these sounds are not produced by they vocal cords. To make these sounds a Manakin brings their wings behind their backs and click them together at 80 hits a second. Picture a hummingbird and how fast they move their wings. Manakins can click their wings faster.
Now back to Micheal Jackson. He might not have know this, but Manakins take on his form of dancing. Like M.J., showing of their dance moves is a way to attract the females. After performing a series of wing movements, they actually hop backwards fast enough to look like the moonwalk. This video will give a better picture of how they perform the dance.

ReferencesManakin. (n.d.). Retrieved from http://www.tropicalbirds.com/manakin.php
Red-capped manakin. (n.d.). Retrieved from http://www.birdwatching-bliss.com/red-capped-manakin.html

P0st #12 - Some weird species
Dumbo Octopus

external image Strange-Dumbo-Octopus.jpg The Dumbo Octopus (from the genus Grimpoteuthis) is can be found in most oceans, but not much is known about them. This is because they are at depths of 7000 meters below see level. Scientists do believe that there are around 37 species of this animal. It is a type of octopus so it is natural that they have eight tentacles. They also have a soft body that allows them to live in deep waters. This octopus gets its name from the Disney movie "Dumbo" about an elephant with oversize ears. It has two fins that are situated and the head where the ears would be found and it uses them to swim. The diet of a Dumbo Octopus consists of worms and crustaceans and it usually eats them whole. Dumbo octopuses also don't have a specific season for mating, but rather do it all year long. The male Dumbo has an enlargement on one of it's tentacles that can transfer sperm into the female and once the female lays the eggs both parents leave them to fend for themselves.

external image 192848339_5db7ab2f6d.jpg The Philippine Tarsier (Tarsius syrichta) is one of the worlds smallest primates. It is around the same size as the hand of a male adult. They live around the base of tree trunks, roots, and sometimes in holes at the top of a tree.The Tarsier has gray tinted fur with an almost naked tail and an elongated middle finger. The one thing people notice first about this primate is its eyes. They are so big that their sockets are larger than its brain case and stomach. The Tarsier also does not close its eyes and this is why it can make an angle of more than 180 degrees with its neck. They are nocturnal creatures and usually hunt insects such as cockroaches and crickets, but occasionally prey on reptiles, birds and bats.


external image 9-axolotl.jpg
The Mexican Axolotls (Ambystoma mexicanum) is a very unique salamander. This is because they do not undergo metamorphosis and keep their larva features as an adult. These features include its tadpole-like dorsal fin and its external gills. This condition is called neoteny, and because of it Axolotls permanently live in water. It is possible for an Axolotl salamander to mature and emerge from the water, but it is very rare. They are very hardy creatures and are the main predators in their natural environment. Their numbers are going down due to introduction of large fish to its habitat. They can grow up to 30 cm and normally feed on mollusks, crustaceans, worms, insect larva, and some fish. I particularly like this species because its cephalization resembles a smiley face :)

Rose, T.M. (n.d.). The dumbo octopus. Retrieved from http://www.environmentalgraffiti.com/animals/news-dumbo-octopus
Hellingman, J. (2004, April 24). The philippine tarsier. Retrieved from http://www.bohol.ph/article15.html
Mexican axolotls. (n.d.). Retrieved from http://animals.nationalgeographic.com/animals/amphibians/axolotl/