User:Grumblis.6/sandbox

User:Grumblis.6/sandbox

Annotated Bibliography
Hofreiter, Michael, Arne Ludwig, Melanie Pruvost, Monika Reissman, Norbert Benecke, Gudrun A Brockmann, Pedro Castanos, Michael Cieslak, Sebastian Lippold, Laura Llorente, Anna-Sapfo Malaspinas, Montgomery Slatkin. "Coat Color Variation at the Beginning of Horse Domestication." Science 324.5926 (2009): 485. Science. Web. 9 Sept. 2014. In this article, Hofreiter and others discussed the progression of coat colors in horses from a period beginning approximately 12000 BC up to 1000 AD. From studying horses in various regions throughout history, they were able to identify an increased variation in coat colors as time progressed. This suggests selective breeding for a more vast selection of coat colors in horses.

Kavar, Tatjana, and Peter Dovc. "Domestication of the horse: Genetic relationships between domestic and wild horses." Livestock Science 116.1-3 (2008): 1-14. Livestock Science. Web. 9 Sept. 2014. In the article by Kavar and Dovc, taking genetic findings in regards to domesticated horses and comparing them to wild horse genetics studied the ideas of domestication. The findings showed implied that the domestication of horses has possibly led to various morphologies and phenotypes in horses. This domestication led to selective breeding, using stallions with the desired characteristics and breeding them with mares.

Lau, Allison N, Lei Peng, Hiroki Goto, Leona Chemnick, Oliver A Ryder, and Kateryna D Makova. "Molecular Biology and Evolution." Horse Domestication and Conservation Genetics of Przewalski's Horse Inferred from Sex Chromosomal and Autosomal Sequences. Oxford University Press, 17 Oct. 2008. Web. 9 Sept. 2014. . The article from Lau and others discussed the relationships between domestic horses and the wild and endangered Przewalski’s horse. The article discussed how domestic horses cannot successfully reproduce with the wild horse, despite being closely related, which implies genetic differences. They studied the chromosomes on the X and Y-chromosomes as well as the autosomes to discover where differences seemed to have rose between the two types of horses.

Vila, Carles, Jennifer A Leonard, Anders Gotherstrom, Stefan Marklund, Kaj Sandberg, Kerstin Liden, Robert K Wayne, and Hans Ellegren. "Widespread Origins of Domestic Horse Lineages." Science 291.474 (2001): 473-477. Print. This article tackled the mitochondrial DNA in horses, which comes from the maternal parent. They used the data to discuss selective breeding that followed domestication, and try to distinguish where genetic variations among the different horse breeds developed. Waran, Natalie, and D Goodwin. "Chapter 1: Horse Behavior: Evolution, Domestication and Feralism." The welfare of horses. Dordrecht: Kluwer Academic Publishers, 2002. 1-18. Print. This chapter written by D. Goodwin from the book edited by Natalie Waran discussed many aspects of horse domestication. He makes several points on how horses have evolved to live in a vast number of habitats. He discusses how domestication for horses has had positive and negative consequences, and how horse breeds in different types of environments differ from body type to energy levels and coloring.

Topic: Has domestication of horses affected them genetically?

Evolution in Horses Due to Domestication Summary of Final Paper
Horses and their ancestors have been around for a very long time. They have lived in many different types of habitats and have been used for centuries by humans, whether it is for farming purposes, travelling, or as pets in modern times when technology replaced them. This domestication may have led to evolution that may not have occurred if the horses were never domesticated and instead left alone in the wild. Even today, horses are still subject to selective breeding. Much like dog breeders, specific horse breeders are looking for certain qualities and keeping them in the gene pool. Horses that can withstand certain limits when it comes to various types of showing, such as jumping, reining, dressage, as well as farm work; such as cattle driving, are being selected for as well. The growing variation in coat color lining up with the domestication of horses is logical, because when animals are domesticated and taken into captivity, they no longer need to defend themselves from predators as much as they did when they lived in nature. They are often guarded by humans or other animals and placed in safe enclosures that would inhibit a predator’s access to them. Since they no longer need to have coats that would hide them from predators, mutations that may have led to brighter, more colorful coat variations that were not necessarily a death sentence anymore. These horses were able to contribute their new gene combination into the gene pool, thus passing on this new color. These phenotypes eventually could lead to mating barriers between the domesticated horse and wild horses, because genotypes may not be present in both types of horse. Domestication chooses for phenotypes that would not be typical in nature. It breeds horses together that might not have had a chance to produce offspring naturally. Horses that are to be bred are chosen for specific qualities, which eventually leads to large differences between domesticated and wild horses. Breeding to obtain a pure pedigree inbreeds animals of the same desired trait, decreasing heterozygosity and increasing homozygosity. As the horses produce more offspring and their offspring have babies of their own, desired traits are going to be selected for and undesired traits will be eliminated from the gene pool. Inbreeding could eventually lead to inbreeding depression, causing the horses reduced health fitness. This could have dire consequences, because the gene pool does not have any other variation to pull the horses back out of the inbreeding situation. Many people looking for horses capable of doing hard work have even created hybrids between horses and donkeys, which is known as a mule. Mules have decreased fitness because they are sterile and cannot produce their own offspring. Domestication affects horses genetically in many ways. Through breeding, genetic variation can decrease. Certain traits are selected for, and continuously breed thus contributing to the future gene pool. Domestication, however, has also increased genetic variations in the terms of coat color. Colors that would not normally survive in nature are able to be passed on to future generations and contribute to the gene pool. Breeding reduces the heterozygosity of the horses, and can also lead to speciation among the domesticated breeds and the wild breeds of horses. Domestication has allowed horses to survive in habitats that they normally would not have ever migrated to, and survive in. It has produced all kinds of horses, while also decreasing variation and separating them from their wild cousins and sister taxa. Domestication has indeed had an effect on horses in several ways, good and bad.

Edit an Article and Add a Sentence
https://en.wikipedia.org/wiki/Evolution_of_the_horse

Suggestions to Add?

 * Maybe add a section about the vast colors of horses, maybe how domestication has increased the possibilities, especially in colors that may be considered less fit in nature. Also how horses were brought over to parts of the world they were not initially native to, and how they evolved to live there (either with the help of humans or not.) And maybe how the genome sequences are similar or dissimilar to the wild Przewalski's horse.

Grumblis.6 (talk) 01:59, 25 September 2014 (UTC)Grumblis.6

Domestication may have also led to more varieties of coat colors. Grumblis.6 (talk) 01:59, 25 September 2014 (UTC)Grumblis.6

Edits to target page (Due Nov 17)
Evolutionary Significances of Domestication Domestication may possibly have led to various evolution paths in horses. Various body types are selected for and against depending on the type of work the horse is being used for. Coat color variation has increased as humans have expressed desired for more uniquely colored horses that may have not originally survived in nature. Horses have also been brought to different places throughout the world that they most likely would not have travelled to (unless they developed serious swimming skills.) Domestication has also created the donkey-horse hybrid known as the mule, and though the mules themselves are not fertile, humans continue increasing their population numbers, a feat that would not happen naturally due to post-zygotic barriers.https://en.wikipedia.org/wiki/Domestication_of_the_horse