2. Introduction: Woolly mammoths were one of the most common herbivores in North America, Siberia, and Beringia until they died out due to excessive hunting and global warming. Small island populations of mammoths however lived until about 3,700 years ago, while those on the mainland went extinct 10,000 years ago. Due to advancements in DNA sequencing, scientists were able to compare the DNA of a mainland mammoth from 43,000 years ago, (when the species was plentiful), and a mammoth from about 4,300 years ago, that lived on the isolated Wrangel Island. Through the comparison, the scientist saw that mammoths from Wrangel Island showed many genetic mutations or changes in the DNA that caused detrimental genetic defects. This discovery should …show more content…
Common Summary: This study focuses on the evolution and of an organism’s genetics over time. In this study, Rebekah Rogers and Montgomery Slatkin from the University of California, Berkley compared the genetic sequences between two specimens of woolly mammoths, from two different environments and population sizes to test the genome evolution theory that small isolated populations of animals will cause an accumulation of detrimental genetic mutations and defects. To identify the shifts in the mammoth’s genetics, Rebekah et al. used ancient DNA sequences to identify the differences in heterozygous and hemizygous shifts in the DNA. Here the scientist were able to observe the deletions, retrogenes, premature stop codons, and point mutations that differed between the two mammoths. Through comparing SNPs, the scientist saw that the Wrangel mammoths had 318 genes with premature stop codons and that some of those stop codons affected the gene codes for the olfactory system and the structure of the odorant binding receptors that give mammals the ability to smell. Also through the comparisons, the scientists found that the Wrangel mammoth had 27,228 deletions compared to the 21,346 deletions in the mainland mammoths. The deletions in the Wrangel DNA effected 1628 bases that coded for synapse functions, urinary protein production, pheromones; and, the deletions on the FOXQI locus in the Wrangel mammoths caused the development of translucent hairs and a satin coat. These deletions had an increase of heterozygosity in the Wrangel mammoths and showed that there were defects in the mammal’s DNA repairing mechanisms. And by using genetic ontology, the results showed that the Wrangel mammoths had 1.3x as many retrogenes as the mainland mammoths. The increase of retrogenes included genes that affected transcription, translation, cell division, DNA repair, and the chaperones of protein
In this paper Martin is arguing that late quaternary or near time extinctions where caused by human activity or as he calls it “overkill”. Martin recognizes that there have been many forces that have triggered extinctions in the planet on the past but disagrees with the idea that near time extinctions where caused by some commonly believed causes like climate change, disease or nutrient shortage. He argues that the arrival of humans to different continents, islands and the subsequent excessive hunting, the introduction of diseases and other competitors and predators was the cause of extinction of a great number of species “As our species spread to various continents we wiped out their large
Paabo’s team discovered an mtDNA sequence from a finger bone they found from around 40,000 years ago, as carbon dating is one of the most commonly used methods of determining a fossil’s age. (Hammer, 70). Also, Neanderthal mtDNA is differs severely from modern human mtDNA. For example, Microcephalin is a gene for brain size during the development of the organism.
Web. The Web. The Web. 11 February 2014 “Biology: Evolution”. The New York Public Library Science Desk Reference.
Wheeler’s analysis of the alpaca mummies also revealed the softness of the alpaca mummie’s hair. It showed that the uniform fibers of the alpaca mummies were finer than those of the modern alpaca. This meant more money for the better quality of the wool. Further research revealed that inhabitants of El Yaral were utilizing pure breeding practices. Wheeler’s research is now focused on the DNA of the alpaca mummies and reproducing that quality in the modern alpaca.
Mitochondrial DNA has a lot of characteristics and features which makes its use very essential in determining the spread of humans throughout the world. Human mitochondrial DNA is solely inherited from mothers. A human’s mitochondrial DNA is the same as his mother’s mitochondrial DNA, which is the same as her mother’s mitochondrial DNA. Researchers can estimate a probability distribution of ancestors’ genes and migration paths through time if they are given a set of mitochondrial gene sequences. It is assumed that all mitochondrial DNA types in the human gene pool can ultimately be traced back to a common matrilineal ancestor that lived approximately 200,000 years ago in Africa.(Oven et al, 386) All human mitochondrial DNA can be traced back to a single mitochondrial DNA known as “mitochondrial Eve”, who lived in Africa a long time ago. Mutations are m...
The question of what caused the extinction of megafauna during the Late Pleistocene period is one that archaeologists have struggled to answer for decades, but why should it matter? Discovering with certainty the cause of megafaunal extinction would simultaneously prove or disprove any of the proposed implications of each existing theory regarding this massive extinction.
The second of Tinbergen’s questions Phylogeny looks at the evolutionary explanations of development, as opposed to just how behaviour has adapted, including mutations in response to environmental changes. Some of these mutations remain in species even after necessity has gone, and can influence future characteristics of that species. The third of Tinbergen’s questions looks at Causation,...
“The Mammoth Cometh” by Nathaniel Rich in the New York Times is an article that details the prospect of “de-extinction” and how scientists within the community have been forming arguments about how to best begin understanding what new technologies are capable of. “De-extinction” is the term given to the process by which scientists can bring back extinct animals, such as the wolly mammoth or the great auk, through genetic engineering. In order to ground the analysis of “de-extinction”, the author focuses particularly on the life of Ben Novak, a scientist, who from a young age, showed an incredible passion for bringing back the passenger pigeon.
Were Neanderthals the same as modern humans, or were they an entirely different species? This is a major topic of debate among Anthropologists, and many people strongly argue each view, backing their opinion with evidence from physical remains and inferred ideas about behavior.
Andrew Isenberg said that “the destruction of the bison was not merely the result of human agency but the consequence of the interaction of human society with a dynamic environment.” Humans and nature both played a large role in the ultimate demise of the bison.
According to Darwin and his theory on evolution, organisms are presented with nature’s challenge of environmental change. Those that possess the characteristics of adapting to such challenges are successful in leaving their genes behind and ensuring that their lineage will continue. It is natural selection, where nature can perform tiny to mass sporadic experiments on its organisms, and the results can be interesting from extinction to significant changes within a species.
The law of club and fang applies to all creatures. Both man and animal are lured by the attractive forces of their ancestry. It is up to them to decide if they are willing to submit to the call and embrace their primitive nature. The Call of the Wild enlightens readers with a story about a dog who yields to said call and renounces his domesticated ways. Jack London juxtaposes the events in The Call of the Wild with those in his life by creating characters that are indicative of mankind, and incorporating the themes of heredity and the influence of the environment on both man and animal and double meanings of places and characters in the novel.
Bison, like many species, have come a long way since the dawn of time. Bison have grown along side humans and humans took advantage of the bison to near extinction. Now bison have been struggling to survive but are luckily still around today but not in every place it used to be. The history of bison go far back to when species are still young on land.
Polar bears prefer to live in extremely cold artic climates. They live only in the Northern Hemisphere, on the arctic ice cap, and they spend most of their time on coastal areas. Polar bears are widely spread in Canada, extending from the northern arctic islands south to the Hudson Bay area. They are also found in Greenland, on islands off the shore of Norway, on the northern coast of the former Soviet Union, and on the northern and northwestern coasts of Alaska in the United States.
Evolution is defined as the change of hereditary characteristics of populations over generations (Caroll, 2009). The environment is continually changing therefore organisms have to change in order to stand the changes in environment so they can survive and reproduce (Caroll, 2009). Regular change in genetic material of organisms over generations can lead to the development of new species that are more adapted to the environment (Caroll, 2009). It is said that failure to evolve may lead to extinction of a species (Caroll, 2009).