User:Walters.597/sandbox

My evolutionary research topic is how giant pandas have evolved due to their environment. http://www.pnas.org/content/103/2/379.full http://www.pnas.org/content/108/43/17714.short http://www.genomics.cn/en/news/show_news?nid=99326 http://web.a.ebscohost.com.cscc.ohionet.org/ehost/pdfviewer/pdfviewer?sid=bf264e34-4579-430f-960b-b75f89c86b7a%40sessionmgr4001&vid=6&hid=4206 http://www.edgeofexistence.org/mammals/species_info.php?id=18 http://web.a.ebscohost.com.cscc.ohionet.org/ehost/pdfviewer/pdfviewer?sid=bf264e34-4579-430f-960b-b75f89c86b7a%40sessionmgr4001&vid=15&hid=4206

https://en.wikipedia.org/wiki/Giant_panda I was unable to edit this post so I but my suggested editing in the talk/edit page.

In this article under Classification there could be more stated to why red pandas and giant pandas are not as related through an evolutionary stand point. Another thing the article could present is under Diet it can mention how 7 out of 13 taxonomic units are unique to pandas than to other mammals (Zhu). Under Subspecies it can be added that 0.3 million years ago a bottleneck occurred that caused the pygmy panda to be replaced by another subspecies - baconi panda that had a larger body mass (Chinese Scientists Discover Evidence of Giant Panda’s Population History and Local Adaptation by Whole Genome Resequencing). I would edit this article by adding "Although red pandas and giant pandas have the same "false thumb" they may of been evolved for different reasons; The red pandas was more than likely an adaptation to aid in locomotion, while the giant pandas may of been evolved for assisting in eating it's bamboo." under Classification where red pandas are mentioned. This will give a little bit more clarity to why they evolved the similar trait, but are only distantly related. Manuel J. Salesa. "Evidence of a false thumb in a fossil carnivore clarifies the evolution of pandas". http://www.pnas.org/content/103/2/379.full. Retrieved 30 September 2014. Walters.597 (talk) 16:42, 1 October 2014 (UTC)

WIKI EDIT UNDER TALK OF https://en.wikipedia.org/w/index.php?title=Talk:Giant_panda&action=edit Under subspecies it says, “Two subspecies of giant panda have been recognized”. In 2012 three have been recognized. An article states, “The more recent panda population history showed that the panda population separated into Qinling (QIN) and non-Qinling populations at about 0.3 million years ago, and then the non-QIN cluster diverged into two populations, the Minshan (MIN) and Qionglai-Daxiangling-Xiaoxiangling-Liangshan (QXL) at about 2.8 thousand years ago”. I would edit the article by stating there has been three subspecies identified within the giant panda population where it says two. Since the article mentions these three subspecies it could also go into detail about their fitness. It can be added that “There has been genetic drift in these three diverse populations and their success varies. The success is expressed in the article that there was a very large decline in the QIN, a slight increase in the MIN and a large growth in the QXL. This shows that the giant panda is evolving and the success of the giant panda is rising with the genetic drift occurring in the populations. There has been an accumulation in positive mutations that became fixed within the population that aids in the success rate of the newest evolved group (QXL). “ Under classification there could be information added that gives evidence that giant pandas are bears rather than a lesser panda. In a phylogenetic study scientists compared characteristics of a gene that binds proteins during mitosis in a giant panda and a black bear. The results were the genomic sequence from Giant Panda is 521 bp, while the length of the sequence of Black Bear is 536 bp, which both contained 2 exons. This showed the genetic sequences were very similar. Walters.597 (talk) 18:45, 16 November 2014 (UTC)

FINAL DRAFT STARTS HERE: TITLE: Giant Pandas are Endangered Bears with a Bamboo Diet and a False-Thumb :TITLE. Giant pandas have been the focus of many scientists for decades. There have been debates on the giant panda’s lineages, fascination with their adaptations, and a lot of studies done on their genetic diversity. Because these animals are endangered, scientists are trying to understand the panda’s evolutionary history to try to aid with the conservation of these animals. Through many studies on the giant panda, scientists have found giant pandas are bears that have several important evolutionary events in their history that explains why they adapted a false-thumb and a diet of mostly bamboo and have become endangered. In early evolutionary studies, there were three hypotheses that classified the giant panda. The first was that they belonged to the family Procyonidae (Wei, Hu, and Zhu 2012). This family includes raccoons and kinkajous. This hypothesis came about because the member of these families has a thumb and so does the giant panda. The second hypothesis was that the giant panda belonged in the Ursidae (Wei, Hu, and Zhu 2012). Ursidea is the bear family. Panda’s body type resembles a bear. The third hypothesis states that the giant panda is a member of its own family, Ailuropodidae (Wei, Hu, and Zhu 2012). The giant panda resembles a bear by its body but not by having a thumb and being an omnivore, so being its own family could be a solution to this dilemma. The first and third hypotheses were based on a phenetic species concept. Molecular genetics, DNA sequences, and many other studies have rejected the first and third hypothesis and accepted the second hypothesis that giant pandas are related to bears. One study compared alpha-hemoglobin and beta-hemoglobin in giant pandas, bears, and lesser pandas. The study showed the bear and the giant panda had a closer molecular phylogenetic relationship than the giant panda and the lesser panda (Hashimoto 1993). Because bears and giant pandas have more molecular traits in common, it proves they are more related than the red panda or any other member of Procyonidae family that had certain phenotypes in common. This study gave evidence that the giant panda shared ancestry with bears. Another phylogenetic study compared characteristics of a gene that binds proteins during mitosis in a giant panda and a black bear. The results were the genomic sequence from Giant Panda is 521 bp, while the length of the sequence of Black Bear is 536 bp, which both contained 2 exons (Yichun, Yi-Ling, Xiang, Wan-Ru, and Jian 2014). This showed the genetic sequences were very similar. This study also gave more evidence that the giant pandas and bears have a common ancestor. The connection between the giant panda and the bear support the coalescence theory. It is thought that the major adaptation that made it unclear that bears and giant pandas are related had to deal with environmental changes (Wei, Hu, and Zhu 2012). The giant panda took a different evolutionary route than other bears did. Giant pandas have two adaptations that today’s bears do not have. One of those adaptations is the false-thumb that confused many scientists and formed the hypothesis that the giant panda is classified with the Procyonidae family. The scientists connected the red panda to the giant panda because of the trait they now concluded is an analogous trait. This is an example of species that were classified together because of a phenetic species concept. Scientists now believe the red and giant panda experienced convergent evolution and evolved the false-thumb for different reasons. The giant panda’s thumb probably evolved to assist in picking and holding bamboo, while the red panda’s thumb probably evolved for locomotion purposes, seeing how they make their habitats in trees. The giant panda’s false-thumb also lacks a flexor brevis digitorum manus muscle the red panda’s thumb has that flexes the hand and makes the grasping action (Salesa 2005). This shows that everything with a false-thumb should not always be grouped together. The false-thumb has become a definitive trait for classifying giant pandas. Another aspect that giant pandas evolved that other bears did not is that giant pandas have a bamboo diet verses a carnivorous diet. Although the giant panda still has all the enzymes needed for a carnivore diet, and does not have enzymes to digest cellulose, its primary source of food is bamboo. Studies have been done to find out how giant pandas digest bamboo and they have found that their guts are very unique. The scientists found thirteen taxonomic units that contained taxa that could digest cellulose. Seven of the thirteen were only found in giant pandas compared to other mammals (Zhu, Wu, Dai, Zhang, and Wei 2010). Since giant pandas began eating bamboo, they have evolved and developed adaptations to help their digestive system break down cellulose and fiber within the bamboo. A reason why giant pandas changed their diet may have been a mutation. The umami taste receptor gene T1R1 has been identified in the giant panda. This mutation would have changed them from carnivores to omnivorous because it gives an organism a desire for good tasting food. An article states, “Since taste is part of the reward properties of food related to its energy and nutrition contents, we did a systematic analysis on those genes involved in the appetite-reward system for the giant panda” (Jin, Xue, Wu, Qian, Zhu, Yang, and Takahrio 2011). Because of this mutation, the giant panda started wanting a savory taste. Continually consuming raw meat would have had a similar effect to humans eating raw meat. If there was a large amount of bamboo around the giant panda’s environment when this mutation for good tasting food arose, natural selection for this mutation would have been great. Before people started becoming a factor in the growth and distribution of bamboo in the panda’s environment, they would have been the only large animal to use bamboo as a resource for food. Facilitating sympatric speciation would occur because the want for bamboo was an ecological character displacement and the resource competition for food between other bears in that environment and the giant panda would be lessened. The giant pandas would start separating from the other bears and then eventually become their own species. The giant panda have gone through many evolutionary events, including two population expansions, two bottlenecks, and two population divergences. (“Chinese Scientists Discover Evidence of Giant Panda’s Population History and Local Adaptation by Whole Genome Resequencing” 2012). The population expansions occurred when the climate was warm and wet because that weather produced the most bamboo. This was when genetic diversity was greatest and the population had reached its maximum amount. Right after this occurrence, the climate changed and became dry and cold. Bamboo does not grow well at those conditions and it caused the pandas to go through a bottleneck. After the bottleneck the panda population began to separate. Within the giant panda population there are six populations that have been geologically separated and that have produced three different genetic populations. An article states, “The more recent panda population history showed that the panda population separated into Qinling (QIN) and non-Qinling populations at about 0.3 million years ago, and then the non-QIN cluster diverged into two populations, the Minshan (MIN) and Qionglai-Daxiangling-Xiaoxiangling-Liangshan (QXL) at about 2.8 thousand years ago” (“Chinese Scientists Discover Evidence of Giant Panda’s Population History and Local Adaptation by Whole Genome Resequencing” 2012). As the populations split off from one another, they evolve and become more fit. There has been genetic drift in these three diverse populations and their success varies. The success is expressed in the article that there was a very large decline in the QIN, a slight increase in the MIN and a large growth in the QXL (“Chinese Scientists Discover Evidence of Giant Panda’s Population History and Local Adaptation by Whole Genome Resequencing” 2012). This shows that the giant panda is evolving and the success of the giant panda is rising with the genetic drift occurring in the populations. There has been an accumulation in positive mutations that became fixed within the population that aids in the success rate of the newest evolved group (QXL). Although the giant panda continues to evolve, they may be on their way to another bottleneck. Due to the climate getting colder and humans taking over the panda’s habitat they have become endangered. Habitat loss has isolated most of the panda populations and that will disrupt the gene flow throughout these populations. This will lead to minimizing the population and genetic diversity within each population (Lu, Johnson, Menotti-Raymond, Yuhki, and Martenson 2001). Allopatric speciation could occur if the populations get completely separated due to climate change and habitat loss. Bamboo does not grow well in colder weather so it could isolate their food source to a limited area. People could also make barriers, such as highways or cities, which cause habitat loss or unavailability to other panda populations. The small populations of giant pandas will lose all their diversity and could have significant downfall. In conclusion, the giant panda has had a rich evolutionary history. It has had two adaptations, a false thumb and a bamboo diet, which no other bear ancestor took, so it became difficult to classify until phylogenetic studies were performed. The panda has also been through several changes in population size and diversity. The endangered species may be experiencing a lack of gene flow caused by climate change or loss of habitat and will lose their genetic diversity. Citations “Chinese Scientists Discover Evidence of Giant Panda’s Population History and Local Adaptation by Whole Genome Resequencing”. 2012. Genomics. Hashimoto T. 1993. The giant panda is closer to a bear, judged by alpha- and beta-hemoglobin sequences. Journal of Molecular Evolution. 282-289. Jin K., C. Xue, X. Wu, J. Qian, Y. Zhu, Z, Yang, and Y. Takahiro. 2011. Why does the Giant Panda Eat Bamboo? A Comparative Analysis of Appetite-Reward-Related Genes among Mammals. 1-8. Lu Z., W. Johnson, M. Menotti-Raymond, N. Yuhki, and J. Martenson. 2001. Patterns of Genetic Diversity in Remaining Giant Panda Populations. 1596-1601. Salesa M. 2005. Evidence of a false thumb in a fossil carnivore clarifies the evolution of pandas. 379-382. Wei F., Y. Hu, and L. Zhu. 2012. Black and white and read all over: the past, present, and future of giant panda genetics. Molecular Ecology 21, 5660-5674. Yichun Z., H. Yi-Ling, D. Xiang, H. Wan-Ru, and L. Jian. 2014. Comparative Analysis and Molecular Characterization of a Gene BANF1 Encoded a DNA-Binding Protein During Mitosis form a Giant Panda and Black Bear. 536-551. Zhu L., Q. Wu, J. Dai, S. Zhang, and F. Wei. 2010. Evidence of cellulose metabolism by the giant panda gut microbiome. 17714-17719.