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Why Only Five Tastes?

Taste_buds

Desireé Mack

Science and Society

                                     Why Only Five Tastes?

 I have all way wondered why Humans have the ability to taste so many things, to what limit can we taste things, and how many taste buds we have. I knew it had to do with making sure our food is not poison but I want to know more. Humans have taste buds to make a choice on what to ingest so we need our taste buds to sample the food to decide what to put in our mouths and what to ingest. When you look at your tongue you see lots of little pink bumps, and in those little pink bumps you have your taste buds. All taste buds are on the outer edges of your tongue. All taste buds can taste multiple flavors because inside them you have multiple cells to pick up the flavor. 

There are five main tastes, one for sweet, sour, savory, bitter, and salty. Animals have evolved to taste sugar to find carbohydrates for energy and a safe source for calories. Animals have evolved to taste savory things to be able to pick up the taste of protein. There are over 25 different types of bitter taste buds to pick out the things that might be toxic to eat and allows us to have enough sensitivity to taste something beneficial in the long run.  We have evolved to taste sour to protect us from eating things to sour that would throw our bodies out of whack and helps us figure out the ripeness of our food for nutritional value. Salt is very important to our biological task our bodies don’t store salt so it is very important that we find foods with salt.


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I Now Pronounce You Chimp & Larry

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Image By:Da Vonte Martin

Scientific evidence has merely proven that humans share a common ancestor with Apes. Yes, that means we have some of the same DNA in fact DNA evidence proves that we share more than 98% of the same DNA.Though we share the same DNA there is an "unknown" ancestor whom takes the credit for connecting the human and ape species.With that being said most people would think that humans are able to mate with apes because the common DNA links them as the "same" species. Humans and apes share some of the same physical features like:

  • Walking up right

  • Thumbs

  • Ability to grasp with all five fingers

  • Similar skull structure

  • Round Ears

Sadly, humans can not reproduce with the monkey specie because that other 2% which makes the ape and human race are the chromosomes. Monkey's have
48 (24 pairs) chromosomes whereas the human body makes up of 46 (23 pairs). In order for any species to reproduce, both subjects need to have their 23 pairs of chromosomes because every chromosome carries DNA which corresponds to the opposite sex which enables them to have children.Though humans and monkeys cannot reproduce now , that doesn't mean that they have then. According to well-known Science Correspondent Richard Ingham, "The youngest chromosome in the human genome is the X, which helps determine gender. On average, X is around 1.2 million years more recent than the 22 non-sex chromosomes, the scientists found.". This means that the X-Chromosome in humans and apes are as recent as the first recorded humans only about seven-million years ago. So not only did humans and apes have sexual intercourse , but they were able to reproduce.Your maybe wondering "I thought humans and apes didn't have equal chromosomes to mate?". That's absolutely right , however more scientific evidence leads to the theory that during the interbreeding of the "unknown" ancestor and apes , two of the chromosomes look as if they had fused together.

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​http://www.synapses.co.uk/genetics/chromos.html
"​Thus something unusual must have happened on the way to speciation: an initial split between human and chimp, followed by interbreeding..." says Richard Ingham.This means that mating between was at one point possible.At one point before the fusion of chromosomes, humans and apes were like opposite genders rather than opposite species. 

Citations:
  • Ingham, Richard. "Early humans had sex with chimps ." News in Science (2006): n. pag. Web. 12 Nov 2010. <http://www.abc.net.au/science/news/stories/s1641443.htm>.
  • Ape, . "Apes." How Stuff Works. How Stuff Works, 16 May 2008. Web. 12 Nov 2010. <http://animals.howstuffworks.com/mammals/ape-info.htm>.
  • Marks, Jonathan. "What It Really Means To Be 99% Chimpanzee ."Department of Anthropology (1999): n. pag. Web. 12 Nov 2010. <http://personal.uncc.edu/jmarks/interests/aaa/marksaaa99.htm>
  • MacAandrew, Alec. "Human Chromosome 2 is a fusion of two ancestral chromosomes ." Department of Anthropology n. pag. Web. 11 Nov 2010. <http://www.evolutionpages.com/chromosome_2.htm>.
  • Rodriguez, Monica. "Ask a Geneticist." Tech Museum:Stanford School of Medicine (2007): n. pag. Web. 12 Nov 2010. <http://www.thetech.org/genetics/ask.php?id=229>.
  • Pbs, Science. "Evolution Frequently Asked Questions." PBS Science (2010): n. pag. Web. 12 Nov 2010. <http://www.pbs.org/wgbh/evolution/library/faq/cat03.html>.
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Whats up with thumbs?

  Everyday we use our hands to do all sorts of task. One of the most important features of our hands is that thing we call a thumb. With the help of having thumbs it has helped humans develop better motor skills. Imagine without our thumbs the things we couldn’t do. Would have our ancestors even developed tools? Would we even be considered as advanced as we are now? Most likely no humans would be.  But how did this opposable thing become on our hand become and are there other creatures with similar appendages?

  When it comes to looking at the evolution of the thumb it is seen with in Homo erectus or Homo habilis. What cause the thumb to become advanced though in our ancestors? A possible idea is the advancement of walking up right as proposed by Suzanna Kemmer. It is thought that as our ancestors began to walk up right there was now new usage for their hands. From this they created tools and learned to use resources that were around. Another possibility is the development of a gene enhancer known as HACNS1 that was found by Yale scientist. The HACNS1 enhancer is thought of as being a “human-specific gene enhancers, which are switches near genes in the human genome.”
 
  Knowing the possibility of our thumb makes us wonder how certain other animals developed their own thumbs. Primates have four categories that divide them based upon their thumbs. There are non-opposable, pseudo-opposable, opposable and opposable long. What causes their classification of thumbs different from ours is the fact that their thumbs do not fully rotate along its axis like our own does. So categories are divided by the amount of independence the thumb has. Other animals with “thumbs” are Giant Pandas (not a actual thumb but a extra bone that functions as one to help them eat bamboo), certain marsupials (in order to climb and gather food) and most birds also have an opposable digit.
 
  Without the thumb or in the case of other animals with thumb like appendages where would they be? Where would we be? Better yet one should ponder with this special adaptation we have what could possible evolve next from it as an adaptation. Will our thumbs slowly change in shape, size or movement? Or will that happen to another species? Who is to actually say what will happen. All we can do is watch what will take place.


Sources:
http://www.primates.com/faq/index.html
http://books.google.com/books?id=5fttVRAHA4MC&pg=PR11&dq=Ankel-Simons,+Friderun+(2007).+Primate+Anatomy+(3rd+ed.).&hl=en&ei=F4zcTNuyKoL78Aaw9JjrCQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDEQ6AEwAA#v=onepage&q=nonopposable%20thumb&f=false
http://www.molecularstation.com/science-news/2008/09/junk-dna-hacns1-discovery/
http://onlinelibrary.wiley.com/doi/10.1002/ajpa.1330150203/abstract
http://www.ruf.rice.edu/~kemmer/Evol/opposablethumb.html
canine-front-paw-bones-compare
thumb
comparison-primate-hands
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Fossils: How much do they indicate? Do they tell the whole story?

Tajh Jenkins

Science & Society

First Quarter Benchmark


Research Question: How much information do fossils indicate about a species evolution? Do they tell the whole story?

I changed my question because my original question just wasn't working out. 

Fossils are witness to the discontinuity, the complexity and the stability of past life forms. When it comes to evolution, fossils are viewed as one of the most important sources of information about the Earth’s past as well as different species past. Fossils are indicators of age (age of rocks and species and animals in which they are found), Earth movements (such as mountain building), ancient geography (former positions of continents), past environments (what the environment was like when the fossil organisms were alive), and the evolution of life (the evolution of life on earth). Fossils give us a showing of Earth’s long history and the all of the changes that it and its species have experienced.

 

Based on this information one would think that fossils are probably the most reliable source of evolution. That is not true. Over time, fossil records have been misinterpreted and have not been able to tell the whole story of evolution. Scientist have been able to point out gaps in fossil record history, proving that some fossil theories are invalid. They say that fossil records fail to illustrate what are called “Transitional Forms” which are the in-between stages of a creature that evolved into another.

 

Fossil records surely do have gaps because of the conditions required to create fossils have been rare ever since life began on earth. A small percentage of animals that have lived and died have become fossils. Many puzzles of the pieces are missing and some may not be found. With that being said, scientists have been able to discover the evolutionary transitions between fish and amphibians, reptiles and mammals, dinosaurs and birds, and lineages such as whales and horses. Fossils have always proved to show existence, but it’s not consistent in showing evolution.

 

When we look at a fossil it doesn’t tell use where it came from or how it was formed. That why fossils still allow us to ask questions about its origin, we can suggest answer these questions by discovering circumstantial evidences.


Resources that helped me:
http://www.docstoc.com/docs/21586403/What-Does-a-Fossil-Tell-Us
http://www.icr.org/article/real-nature-fossil-record/
http://www.ucg.org/booklets/EV/creation-evolution-fossil-record.asp
http://www.trilobita.de/english/intro.html

http://www.biologos.org/questions/fossil-record/
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Humans: Converting From Omnivores To Herbivores

Humans eating meat dates back to habits used by the Australopithecus. Through out the span of around 5 million years humans have gained certain tools to aid us in eating meat. Humans have adapted sharper teeth that allow us to tear through meat easier, but what if due to the growing diseases that are being carried by animals, humans as a whole began to convert to veganism (vegetarians)? Would the teeth that have helped us chew meat begin to fade out of the human race? 


Ever since early man, meat has been a part of humans diets. Of course 5 million years ago meat probably wasn't as carefully prepared as it is now. Through out the 5 million years of our existence we have gained a few tools to aid us in consuming and digesting meat. First we gained two sets of teeth, one set on the upper row of teeth, and one set on the lower set of teeth that are sharper than others and help tear meat, we have also gained the ability to digest carbohydrates and fats better. 


In a study done by the University Medical Center in Dallas Texas, there are some characteristics that humans have that also resemble those of plant eating species. Most carnivorous species have small intestines that are around 3 times their body length, and most herbivorous species have small intestines that are around 12 times their body length and humans small intestines are closer in length to those of herbivores species. 


If humans as a whole began to cut meat out of their diets a few things would began to change, the sets of sharpened teeth would no longer be needed so they would begin to fade away through the generations. Also humans would possibly lose their ability to digest fats and carbohydrates as well, which would mean carbohydrates would become less common. 


After looking over the various tools and adaptations humans have gained in order to consume and digest meat, it has become apparent that if those tools and adaptations aren't used they will begin to show less and less in newer generations. Which means that humans will begin to lose the teeth that we have gained to help us eat meat. 


Here are some links that aided me in my research

http://www.rense.com/general20/meant.htm

http://news.nationalgeographic.com/news/2005/02/0218_050218_human_diet.html

http://www.straightdope.com/columns/read/674/are-humans-meat-eaters-or-vegetarians-by-nature

http://www.newscientist.com/article/dn4122-meat-eating-is-an-old-human-habit.html


While doing this research I began to form a question in my head that seems to me would be interesting to research, why can't humans just live off of fruit? A lot of fruits can give us the necessary sugars needed for survive, and for all of the other necessities humans can just rely on vegetables? Just a thought.

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"Hanuman Langurs: Evolution and Social Behavior"

How Does Evolution Impact the Social Behavior of Hanuman Langurs?

hlangur

The Hanuman Langur is an Asian monkey; whose social behavior is uncanny. Their troops consist of both males and females numbering around 125. The head male—of a troop where there is one male—is competing with other males to maintain his position as leader. When a group of males overthrow the leader —so to speak—they kill his offspring. After that “ritual” one male becomes they new leader. That male then mates with the females of the troop and the process is repeated. The males gain a reproductive advantage because the females are at their maximum sexual receptivity when they lose their offspring.

·      This species is vulnerable to infanticide.

·      Males attack the infants only if they were not present at the time of contraception.

·      The males are usually protective of their offspring, however some still kill their own young.

 Ecology, Social Structure & Evolution

·      Ecology pressures that influence sex ratio populations also affect group size and social structure.

·      Increasing the Hanuman Langur troop size might prevent takeover and infanticide.

 One study reports that species such as:  P.ursinus, Propithecus diadema, and Semnopithecus entellus (Hanuman Langur) have over a 10 percent mortality rate of infants. Another species, the Red Howler species, shows that the rate of infanticide increases with group size. However, there was a change in rate when the Red Howler groups became large enough to cause paternal confusion—the males in the species normally do not kill their own young. The confusion causes males refrain from infanticide, which causes an overall decrease in the infanticide rate.

Because the social behavior of the Hanuman Langur depends on ecology...ecological evolution impacts the behavior. The ecology of the Hanuman Langur includes varied troop sizes and varied troop constituents, which evoke different behaviors. As previously stated, troop size impacts the level of infanticide.

Questions for Research

What does the social behavior of hanuman langur imply about evolutionary desires to be a leader or at an advantage by any means?

What does this behavior say about evolution in general?

Hanuman Langur selectivity and evolution…

Sources

www.eva.mpg.de/ipse/pdfs/Ostner_etal2006.pdf

http://chapmanresearch.mcgill.ca/publications.html

http://www.theprimata.com/semnopithecus_entellus.html

http://www.cabrillo.edu/~crsmith/hanumanlangurs.html           

 

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Disease: Evolution in Humans Vs. Animals

Question: How do diseases in animals and diseases in humans show the different evolutionary paths that we have gone down and what does it say about our immune systems?


Animals and humans can get the same diseases but to my knowledge there are some diseases that we are immune to that they aren't and vice versa. Humans have had an advantage for the past century or so with having plumbing access to for the most part clean water and other means to prevent and fight diseases. Penicillin and amoxicillin are among pills that are made to fight and prevent diseases. Animals on the other hand have evolved in the wild where they have to rely on natural selection and how they have evolved to adapt in their environments to fight off sickness and disease.


Zoonotic diseases are diseases naturally able to transfer from animals to humans and vice versa. This shows that we share some of the same immune system capabilities as animals. For instance it is known that while sharks are able to get cancer their immune system prevents cancer/tumors from being able to grow.The recent Swine Flu outbreak is recent evidence of this resulting in many people becoming ill and around 12,000 actual deaths in the U.S. in the recent 2009-2010 outbreaks, and shows how diseases originate in animals and transfer to humans. AIDS however is a disease that cannot from my knowledge and research thus far, be contracted by animals except for in chimps. Is this because of our DNA similarities and because of the similar evolutionary path that we have gone down? Also, how has the evolutionary path of diseases influence how and who it effects between animals and humans? What about the sharks? Has evolving in the ocean over these millions of years gave them a sort of advantage from not letting cancer or tumors progress?

These following links show other diseases and how either vaccines are similar or animals and humans can contract similar diseases.


http://news.bbc.co.uk/2/hi/health/7270562.stm

http://www.mrmcmed.org/aids.html

http://biology.clc.uc.edu/courses/bio105/immune.htm

http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=imm&part=A1480

http://www.nature.com/nature/journal/v248/n5446/abs/248344a0.html

http://www.elasmo-research.org/education/topics/p_bite_on_cancer.htm

http://pin.primate.wisc.edu/aboutp/pets/zoonoses.html



k7438
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Evolution and Attraction

Camille Maldonado
Benchmark 1


How has evolution influenced mans attraction towards woman and how does culture come into play?

In Mauritania, a country located in Northern Africa, and odd custom has become the center of fear for young girls living in the rural areas within the country. The practice that has become so intriguing and important is the act of force-feeding young girls. Girls even around the age 5, against their will, are being force-fed large amounts of food and liquids. What’s worse is that while being force-fed if these girls happen to reject the food by vomiting they are also force-fed whatever they had regurgitated. This is influenced by the importance of marriage to the future these young girls, the bigger the woman the better chance she has of marriage.  

Around the world we so many different example of the ideal woman and all of these examples happen to be some how influenced by evolution.  The way men tell how a woman is a perfect mate for them is by looking at the body and evaluating if she contains the certain traits needed for reproduction, the same goes for how woman pick their men. However, each place in the world has their altered beliefs on what is the “perfect”, this is not only influenced by evolution but also  impacted by the different cultures within these countries.

Young girls from these rural places are taken to “fattening farms” where a family member, most likely their aunt or grandmother, will feed them the large quantities of food. To hurry the fattening process matrons will use sticks to roll on the thighs of these girls and cause the tissue to break down quicker. Fatima M’baye,  who is a children’s rights lawyer says that when these girls reach the age of 15 they will most likely look as if they were 30 years old.  Aminetou Mint Ely who is a woman’s rights activist has seen the impact that force-feeding has had on these young girls. Since she has been around this culture for a while she is able to determine and find out why the force-feeding is so important and what it means to the people of Mauritania. Mint Ely says, “a woman's size indicates the amount of space she occupies in her husband's heart...The military have set us back by decades, sending us back to our traditional roles.” Mint Ely determined the reason behind this odd custom and also gives insight to why this old tradition has been brought up again.

Some studies have shown that men, despite the different countries they may live in, share the same idea of what traits are attractive in a woman. This may sound odd especially when in Western culture it seems as though the ideal woman is slim and not fat at all. Yet, this doesn’t mean that the study is wrong it just means the culture and evolution go hand in hand when it comes to what is attractive to a man or woman. Evolutions main influence on our preference has to do with reproduction, not health. Woman are attracted to muscle and strength but its been shown that men who have a lower amount of muscle mass are much more healthier. Also, men seem to like woman who have prominent feminine features, this relates to the idea that “hour glass figure” is what men want. Even so  this doesn’t mean that the woman is healthy it just proves to the man that the woman's body is more suited for reproduction.  In Mauritania a fuller body is representative of the ability of the particular female to reproduce. In Western areas a body that is slender and fit represents the strength and health  that the  woman needs when enduring the side effects of reproduction. Each country and culture has its contrasting views on the “ideal” woman. Nevertheless, the general demand is the capability of a woman to reproduce. Evolution has hardwired our selection process for the means of survival, because without reproduction our species would no longer live.




SOURCES:

http://www.suite101.com/content/the-evolution-of-sexual-attraction-a51994
Wadson, Kelly. "The Evolution of Sexual Attraction." suite101 (2008). Web. 4 Nov 2010.

http://www.uclshrp.com/bulletin/news/mauritian_military_regime_turns_a_blind_eye_to_force_feeding_for_marriage/   
"Mauritian military regime turns a blind eye to force feeding for marriage ." uclshrp.com (2009) Web. 5 Nov 2010.

http://www.guardian.co.uk/world/2009/mar/01/mauritania-force-feeding-marriage
Duval Smith, Alex. "Girls being force-fed for marriage as fattening farms revived ." guardian.co.uk (2009). Web. 4 Nov 2010.

http://www.questia.com/PM.qst?a=o&d=27177257
Buss, David M. The Evolution of Desire: Strategies of Human Mating. New York: HarperCollins (1994) Web. 6 Nov 2010.

http://psycnet.apa.org/?&fa=main.doiLanding&doi=10.1037/0033-2909.131.5.635
Weeden, J., & Sabini.  Physical Attractiveness and Health in Western Societies: A Review. Psychological Bulletin (2005) Web. 5 Nov 2010.

Mauritanian-women-wait-to-001
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Etienne Geoffroy Saint-Hilarie Theory

Q1 Science In Society Benchmark

“Evolution Blog Post”

 Question:  How is Etienne Geoffroy Saint-Hilaire theories impact the era at the time and paved the way for future evolutionist?

            Etienne Geoffroy Saint-Hilarie once said “Nature ... tends to repeat the same organs in the same number and in the same relations, and varies to infinity only their form. In accordance with this principle I shall have to draw my conclusions, in the determining the bones of the fish's skull, not from a consideration of their form, but from a consideration of their connections.”

            Sanit-Hailarie derived this quotes from his theory on animals sharing the same characteristics regardless of an animals origin. He made several comparisons with animal’s connection opposed to their connection to one another.

Etienne Geoffroy Saint-Hilaire a profound French naturalist created the principle unity of composition. In 1772 Etienne came into this world and impacted forevermore the way we look at the modification of animals overtime.  The Herbet Spencer, Darwin, Patrick Mathew and many more wouldn’t have based there theories on the evolution of life if he didn’t pave they way.

Etienne took over the early 1800s with his theory then later Darwin evolved his theory to conclude natural selection many decades later. In giving him full credit is ignoring his early influence Etienne Geoffroy Saint-Haire who was his professor.

            The concept of an animal forming the same elements sparked a controversial impact in the 1800s. In actually believing that animals shared the same features baffled the unknowing scientific world. Etienne friend Curve heated over large misconceptions that lead to there ending friendship.

Sources

http://www.wordiq.com/definition/Etienne_Geoffroy_Saint-Hilaire

http://www.answers.com/topic/isidore-geoffroy-saint-hilaire

http://www.highbeam.com/doc/1G2-2830905695.html

 

 

 

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pentadactyl
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How the origin of life through the understanding of evolution is factual if it's contradicts the knowledge of cells?

Charles Darwin's theory of evolution is the widespread belief that all life is related and has descended from a common ancestor and that birds, fruits, fish and reptiles are all related. It is said that complex creatures evolve from more simplistic ancestors naturally over time. Many people believe it is a fact, but the theory of evolution is flawed and that is why it is only a theory. How can evolution be true if it contradicts the knowledge of scientific things we already understand?

The beginning of life through the theory of evolution came along by chance. Science shows that in order for a cell to survive and reproduce, it must have DNA, RNA and proteins, which are complex molecules. What is the probability that DNA, RNA and protein formed by chance? RNA is needed to produce proteins but at the same time proteins are needed in the production of RNA transcription. One couldn’t exist without the other. What are the odds of both RNA and protein appear by probability at the same time and place?

The way cells work and are made are too complicated to be made by chance through evolution. The probability for every cell to know it’s job in the body and work in harmony for it to properly run the body is nearly close to zero percent.

Marshall Brain, author of the article “How Evolution Works” said that the first living cells had to possess “A cell wall, the ability to grow, the ability to process other molecules floating outside the cell as food to create energy and the ability to split itself to reproduce.” How did a cell know how to do these things in the beginning of evolution? It takes time for a trait to be pass on but the chance of all these traits to already be given to the first form of life is low. Even though some things have been proven factual in the theory of evolution such as natural selection, the origin of life from the theory of evolution is hard to believe.


Sources:
http://www.associatedcontent.com/article/1097583/types_of_cells_in_the_human_body.html?cat=5
http://nobelprize.org/educational/medicine/dna/index.html
http://science.howstuffworks.com/environmental/life/evolution/evolution.htm
http://www.darwins-theory-of-evolution.com/
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