Saturday, November 2, 2019

Theory of Evolution and Evidence for Natural Selection Assignment

Theory of Evolution and Evidence for Natural Selection - Assignment Example Evolution occurs at different paces for different species. While it took a very long time for human beings to evolve from ape like primates into the modern Homo sapiens, for simpler organisms, evolution occurs over smaller time frames. For instance, quite a few bacteria have become resistant to anti-biotic drugs. Anti biotic drugs have been used only for the last eighty odd years and initially the bacteria could be killed by these drugs. But in recent times through evolution, the bacteria have become resistant to these anti-biotics. Evolution is caused by a process know an â€Å"natural selection† which was first coined By Charles Darwin in his famous book â€Å"On the Origin of Species† published in 1859. The idea behind natural selection is that certain features provides organisms with advantages that lead to easier survival in the environment. And this survival in turn leads to passing on of these features into future generations. A good example is that of the long neck of the Giraffe. Since longer necks allowed the ancestors of the Giraffe to access food located higher or more difficult places, those with longer necks survived better and thus the genes of the longer neck got passed on to future generations. Over time, the neck grew to the very tall stature that we observe today in the present day Giraffe. Taxonomy Taxonomy is the scientific classification of all living species. The classification is based upon a system of rankings. The primary unit in the process of classification in the domain of all living things is the â€Å"kingdom†. ... There are 5 possible kingdoms and all living things belong to any one of these with the notable exception of some symbionts like lichen which belong to two kingdoms. These are as follows: 1. Monera/Prokaryotes: simplest living organisms such as archaea and bacteria 2. Protista/Eukaryotes: unicellar organisms, i.e., living organisms with only one cell. 3. Fungi: moulds, mushrooms etc belong to this class. 4. Plantae: all plant life belongs to this kingdom, so instances are trees, grass, moss etc. 5. Animalia: is the kingdom of all animals which includes humans. The second rank in the taxonomy belongs to the Phyllum. So, the members of a certain kingdom are classified into different Phylla (plural form of Phyllum). Each Phyllum in turn is split into classes, and these classes are further divided into orders. For example, meat eating animals, known as â€Å"carnivora† are an order. These orders are further classified into families. The cat family, dog family etc are instances of families that belong to the â€Å"carnivore† order. Closely related members of each family are clubbed together under a â€Å"Genus† and the members of each genus which mate naturally are termed a â€Å"species†. There are many species in the world. For instance the crow and the raven, although similar are different species. But they belong to the same genus. These and other genus such as the magpie constitutes the crow family. The crow family along with other families such as the thrush family, swallow family are members of the order of â€Å"songbirds†. Songbirds belong to the class of â€Å"birds† and these are the members of the phylum â€Å"vertebrate†, and vertebrates belong to the kingdom â€Å"Animalia†, or the Animal Kingdom. Population Dynamics Population

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