Microevolution occurs when a species has almost insignificant genetic changes over time. The studies performed on these small genetic changes are usually tested over very short time periods (decades to a few hundred years). This is because it is difficult to find ancient DNA specimens to compare to the modern species. However, because of the frigid and preserving terrain Adelie penguins are the perfect research candidate. This specie of penguin lives, breeds, and dies all in the same location of their ancestors before them; leaving plenty of ancient remains. The researchers compared the DNA of the ancient (6,000-year-old penguins) to the modern descendants. This comparison revealed that some of the Adelie penguin genes became longer over time
and some new variations of genes came into existence, while others had been phased out. The modern Adelie penguins were also compared to other penguin colonies in the surrounding area. Surprisingly, there was not a lot of genetic variation between the colonies. This comes as a surprise because the generations of Adelie penguins live, breed and died all in the same location. This would create a significant genetic difference between the Adelie colony and other colonies. However, something has caused the penguins to interbreed with the other colonies around them. The claims is this article have quite a bit of validity to them. The evidence is supporting the fact that the Adelie penguins live, breed, and die in the same location and have been doing that for thousands of years. This would cause very little genetic variation within the population. However, if a penguin was the go off course because of iceberg chunks blocking their swim path, it is likely that the penguin would find another colony and mate. This would cause variations in the Adelie penguin gene pool. This claim would also support the fact that the penguins within the surrounding area had little genetic variation compared to the Adelie penguins. The only question is: Does a large number of broken off chunks of mega-icebergs affect the Adelie penguins’ swim path and force them off course?
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.
People normally tend to assume that plants in the past vary in differences and traits compared to species that are present. People have the impression that the past species had diverse weather conditions and nature related incidents forcing them adapt and become different from others. In the book, Andrew Knight had the idea that the food that was available could have tampered with their genes. Reproduction could have something to do with species changing. With plants, minor situations could determine whether they disperse a seed. It happens quickly and changes the genes of the plant causing a new formation that is disseminated through plant. Reproduction inheritance of genes is an important aspect when trying to determine ancestor’s life. By studying these pigeons, Darwin decides that all pigeons have originated from the rock-pigeon. Many people believe that pigeons have descended from a numerous amount of species and birds. Pigeons mate for life and by doing so the breeds are kept together and have markings in same areas of body. They mold into different species as years have passed because of the natural selection or an idea that Charles called unknown selection.
The female moves her head within the avenue walls during the male display, providing her with motion parallax depth cues that will conflict with the false depth cues of forced perspective.
Grens, Kerry. "Lost Colony DNA." Scientist 26.1 (2012): 16. MasterFILE Complete. Web. 23 Oct. 2013.
For this evolution project, I choose to research Penguins. The classification for this animal is as follows: K Neornithes, P Palaeognathae, C Neognathae, O Pelecaniformes, F Procellariformes, G Graviidae, S Spheniscidae. The first fossil penguin that was found, is today being held in the British Museum of Natural History. It was reportedly found by an anonymous Maori in New Zealand in 1859 and was named Palaeeudyptes Antarcticus despite the fact that the species was located far away from Antarctica. Since that discovery many more fossils were found and were dated back to the Miocene era and three others from the Pliocene era. Several fossils were dated to the Late Pliocene era and others from the Recent era. The earliest avian fossil found in the southern hemisphere is said to have existed in the Eocene age about 38-54 million years ago. There is evidence that at least three of the modern penguins (Aptenodytes, Spheniscus and Pygoscelis) went extinct within the last 4-5 million years. The remainder of the penguins are from 5-40 million years ago, dating back to the time currently recorded, when penguins evolved from other modern birds. Research suggests that the tallest of these penguins were about 6 feet tall. Penguins did originate from an ancestor that flew some 40 million years ago. The common ancestor is assumed to have been somewhat similar to a modern-day diving petrel or auk in appearance and behavior.
If puffins are disturbed by humans they will leave their nests and will not come back. This has led to the extinction of puffin colonies in parts of the European coastline.
According to Klug, &Ward (2009), members of a certain population from another are distinguished by the presence of unique genetic characteristics. It is believed that large populations have greater diversity of alleles, compared to the small populations. In most cases, the diversity of alleles designates a greater potential for any evolution of new genes combination. This also shows greater capacity for evolution in adapting different environmental condition. On the other hand, individuals in small populations are possible to be hereditarily, anatomically as well physiologically more consistently than in large populations.
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.
These penguins lived after the Castastrophic event “Cretaceuous” that demolished the dinosaurs and many other species. Based on the DNA analyses and avaiable evidence of modern birds, we think the modern bird- lineages, including penguins, some how managed to survive through the Cretaceuous. Also it’s not shocking these fossils were found in New Zeland. The South Pacific and Southern oceans were free of predatory mammals, had abundant food, and had space for Penguins to breed. But the Southern Pacific is not the only area where Penguins inhabit. Many of modern penguins “Aptrenodytes” are located in the Antarctic. Recenelty it was discovered that there was a over looked feature on the surface of the fossil penguins flipper bone. These grooves were easily missed because the look was similar to tendons and muscles in the same area. It was discovered that these grooves were blood vessels that make up a counter current heat exchanger called “humeral arterial plexus” which allows penguins to limit the heat loss through the flippers. Also it helped Penguins maintain their core body temperature in cold water allowing them to survive long journeys in the cold waters. Although Penguins have luckily been able develop these traits to survive the dramatic shifts in climate, the world population can not mistake their success as resilience towards global warming.
The Galapagos Islands, located about 600 miles west of continental Ecuador, contain a rich history of settlement and exploration and represent a living example of evolution that is still relevant today. For centuries, this chain of volcanic islands has been used uniquely by various cultures based off distinct needs. What has remained the same however is the fact that island isolation has forced many animal and plant species to adapt differently from one another based off their island’s environmental conditions, creating a living model of microevolution over time. Today, these models tend to be the primary resources used by biology professors when teaching their students evolutionary topics.
On our Earth, we are graced with many fantastic life forms. From those gliding through the heavenly skies, to those at the deepest depths of the oceans, there is a plethora of various species. A group of these, though, is like a diamond in the rough. While many people admire its beauty, they have yet to realize that it’s the love for them that is dwindling its population. Who are these magnificent creatures…none other then the penguins.
No one knew how heredity (passing traits) worked until Gregor Mendel, an Austrian monk, crossbred pea plants in his monastery kitchen garden in 1865. In 1869, gene-hunters found rod-like shape in the nucleus of cells that turned red when dye was added. They named this “Chromosome”, from a Greek word, chroma for color. They also went deeper into the cell and discovered a wispy microscopic thread within the chromosomes, which they named DNA. There were several scientists who did not know about Mendel’s breakthrough at the time, but then in 1900, they rediscovered his experiment and old journal copies.
Darwin’s observations from the islands made him want to come up with some explanation to why this occurred. He began to do research of each the species that had lived on these islands and observe all of the characteristics that had. He noticed that the islands h...
Although modern evolutionists are thought to be divided on the issues surrounding evolutionary theory, a close look at the evidence suggests that both the gradualist school of thought and the punctuationist school of thought share many characteristics in common. This is especially true when evaluating their beliefs about the fossil record, disagreement with the theory of saltation, and the misinterpretation of the word “rapid” in terms of punctuationist theory. Although this may be the case, the two theories do diverge on one important point, the notion of periods of stasis, but when taken as a whole, the evidence suggests that punctuationism is not as radical as it has been hyped up to be.
On Darwin’s trip around the world he found something very interesting on the Galapagos Islands. On the isolated islands he found fourteen species of finches with very similar characteristics but they had some differences in their beaks, diet, body size and habitat. Darwin thought the birds had a common ancestor. He thought that some time back some finches arrived on the islands and the finches with the beaks that suited the islands conditions survived this happened on all the islands. When they had offspring the next generation would inherit the same beak. This is a great example of natural selection which was a contributor to how humans evolved. From this Darwin established his theory of natural selection and how slowly over time creatures...