Kennedy+G.

=**__Unit 2 Evolution: Evolution of //Equus//__**= This is an example of how the Eohippus has evolved into the Equus (Modern Horse) media type="custom" key="24572304" Here in this video you get a strong detailed message on how the Equus has evolved from the Eohippus. I find this video gives a good strong visual on how the animals have changed, although sometimes it is confusing with two voices the visual picture gives you a quick time on how things changed.
 * // Due November 29,2013 //**

The evolutionary linage of the horse begins during the Eocene Epoch time period (55.8 million to 33.9 million years ago) through until today and is one of the best documented animals in paleontology. During the beginning the first ancestral horse was a hoofed browning mammal called the //Eohippus//,the Dawn horse. There have been fossils of these creatures in both North America and Europe that showed the animal stood between 4.2hh and 5hh (1.4 to 1.7ft) with an arched back and raised hindquarters. Their legs ended with padded feet and four functional hooves (toes) on each of the forefeet and three on the hind legs. Unlike the modern horse which has a single unpadded hoof. The skull lacked the large flexible muzzle area of the modern day horse and the size and shape of the cranium area indicated a much smaller brained was less complex.Their teeth were significantly different as well where their died was made up of leaves, shoots and twigs where as today's animal has a browsing diet. It wasn't until paleontologist had unearthed foosils of the //Eohippus// that they were linked to the modern day horse. The //Eohippus// lived in the forest making it easy to hid from predators. This animal diverged into two other species that resembled a horse. Fossil of the //Eohippus//
 * Eohippus**

//**Oligohippus**// The //Oligohippus// evolved from the //Eohippus// 36 million years ago about 40. This animal was slightly larger but lived in the forest just like the //Eohippus//. The //Oligohippus// had three hooves that touched the ground but the fourth that the //Eohippus// had disappeared. They had also had a larger skull and weighed 40-55kg.

During the Miocene Epoch the //Merychippus// was found. This animal was pony sized and had an even bigger skull that the //Oligohippus.// The three hooves still remained but the only functional one was the middle "toe". These animals lived in grasslands making it easier for them to be preyed upon so they had to have longer legs that were stronger to run with. They moved to the grassy lands as they became more popular as their orignal food was becoming scares. These new sources were a rich source of food for the animal which adapted well to the grazing habits. It was about 10hh. An idea of how the //Merychippus// looked like based on fossil and bone evidence.
 * //Merychippus//**

//**Pliohippus**// The //Pliohippus// evolved around 7 milllion years ago from th//e Merychippus//. . Foosils have been found in Colorado, the great Plains of the Us and some in Canada.Gradually they lost the side toes they are believed to be a direct ancestor to the modern horse. They has a skull with deep facial fossa with curved teeth where the modern day horse has no facial fossa and their teeth are very straight. The //Pliohippus'// bone structure and body structure.

The early //Equus// has zebra like bodies and a head similar to a donkey. They had tails but they were short and stiff with straight up manes. They had meduim sized ears, striped lets and some striping on their back. Many of the other strains of the horse died off for reasons that are still unknown but this species thrived forward. We began seeing evidence that was about 5 million years old to present day. We see the species in horses, asses and zebras and fossil evidence is found on every continent except Australia and Antarctica. The early //Equus// such as the Przewalski's Horse
 * //Equus//**

//**Equus Caballus- further information.**// This is the modern day horse that we see today. This is the animal that was domesticated and has impacted human history signifcantly in areas such as migration, farming, warfare, sport, communication and traveling. Today's horse.

Throughout the 20th Century numerous theories have been developed to explain where and when the domestication began and what the purpose of it was for. A basic summarization of the different theories is that it began the Neolithic, Eneolithic or Early Bronze age in the Ukraine, Kazakhstan, Eastern Europe, Western Europe or the Near East. They domesticated them for meat, riding or traction. In some situations it was very easy to show how and why they were used in ancients by the material that was left behind such as bridles, saddles and harnessing equipment where as other situations items are hard to come by as they were organic materials such as leathers and wood where are rarely recovered from the archaeological record. Although there isn't the evidence that these items were always used, it is possible to ride a horse without these items and during the early stages of domesticating horses they likely to be ridden without these items.
 * Domestication **
 * Tell-tale signs of ‘bit damage’ found by researchers in Kazakhstan are evidence that horses were harnessed and may have been ridden as early as 5,500 years ago. **

A short but interesting article that is fairly recent "Archaeologists Find Early Signs of Domesticated Horses" []
 * Further Reading:**

This article explains briefly horse Evolution to not bore an individual "Horse Evolution and Brieft History" []

A basic read on how the horse Evolved "The Evolution of the Horse" []

A more complex read with more detail of the Horse "Evolution of Horses" []

Sources: http://research.vet.upenn.edu/HavemeyerEquineBehaviorLabHomePage/ReferenceLibraryHavemeyerEquineBehaviorLab/HavemeyerWorkshops/HorseBehaviorandWelfare1316June2002/HorseBehaviorandWelfare2/DomesticationBreedDiversificationandEarlyHis/tabid/3127/Default.aspxSources

-http://www.britannica.com/EBchecked/topic/1900351/Tracing-the-History-of-Horse-Evolution-and-Domestication-Year-In-Review-2012/308506/Origin-of-Horse-Domestication

-http://www.britannica.com/EBchecked/topic/1900351/Tracing-the-History-of-Horse-Evolution-and-Domestication-Year-In-Review-2012

-http://www.ecology.info/horses.htm

-http://chem.tufts.edu/science/evolution/horseevolution.htm

=**__Unit 1 Genetics: The Risks of Cloning in Animals__**=

= = First Mammal Successfully Cloned In today's society there is a lot of talk on cloning, but many fail to realize the risks involved in the cloning process.

media type="custom" key="24075212"The Process of Cloning Dolly, how cloning is done! There can be loose ends to cloning, this one happened to go right.

=== When we hear about cloning all we hear about are the successes but what isn't ever talked about are the amount of failures that arise before the success happens. But, is the success really a true success? Not always later on in the clones life their can be problems that will arise. ===

Are you willing to let this happen?> This is a failed attempt at cloning a dog.

There is a high failure rate:
-"The success rate ranges from 0.1 percent to 3 percent, which means that for every 1000 tries, only one to 30 clones are made." Problems that could arise later in life: - "Clones tend to be born much larger. Scientists call this "Large Offspring Syndrome" (LOS). Clones with LOS have abnormally large organs." Abnormal Gene Pattern: -"In cloning, the transferred nucleus doesn't have the same program as a natural embryo. It is up to the scientist to reprogram the nucleus, like teaching an old dog new tricks." Telemeric Differences: -"As cells divide, their chromosomes get shorter. This is because the DNA sequences at both ends of a chromosome, called telomeres, shrink in length every time the DNA is copied."

This is a basic explanation of each risk from the University of Utah. Quotes can also be retrieved on their websites along with further detail into each problem. []

More Risks
Life Span: <span style="font-family: 'Comic Sans MS',cursive;">-Significantly shorter life span than the average animal. <span style="font-family: 'Comic Sans MS',cursive;">-Along with suddenly dying <span style="font-family: 'Comic Sans MS',cursive;">Delivery upon arrival: <span style="font-family: 'Comic Sans MS',cursive;">-During the birth of the clone there can be more complicated than a normal animal pregnancy. <span style="font-family: 'Comic Sans MS',cursive;">Another Note: <span style="font-family: 'Comic Sans MS',cursive;">-Cloned animals also have a low success in reproducing. Some people have wanted their animals cloned because the previous animal was either spayed or castrated and the owner would like to carry the genes on. This isn't always working as some of these clones are infertile.



<span style="font-family: 'Comic Sans MS',cursive;">Links you may find Interesting

 * <span style="font-family: 'Comic Sans MS',cursive;">[] Big risks in cloning animals.
 * <span style="font-family: 'Comic Sans MS',cursive;">[] First cloned hybrid animal, which normally can't reproduce.
 * <span style="font-family: 'Comic Sans MS',cursive;">[] 90% of clones die during trials.
 * <span style="font-family: 'Comic Sans MS',cursive;">[] Cloned Animals are a possible threat to genetic diversity.

<span style="font-family: Tahoma,Geneva,sans-serif;">One of the many attempts to clone a calf worked, <span style="font-family: Tahoma,Geneva,sans-serif;">but just worked for now. The question is the underlying problems later in its life.

<span style="font-family: 'Comic Sans MS',cursive;">More Sources:
 * <span style="font-family: 'Comic Sans MS',cursive;">[]
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