Extinction
Punctuated Equilibrium
Evolutionists for generations after Darwin imagined a slow and steady process of adaptation, in which daily culling and breeding success very gradually adapted a population from one form into another. Such a process would not be dissimilar to unnatural selection, such as that done with domesticated animals, that gradually worked to change a wolf into a little Cairn Terrier or Shih Tzu. However, some have suggested that there might be a more sudden sort of change involved, in which evolution moves suddenly and with great speed. This theorized form of evolution, called punctuated equilibrium, has been widely debated, but seems to be increasingly accepted by scientists. There appears to be evidence for punctuated equilibrium from laboratory experiments, from field and fossil evidence, from theory and even from Darwin's original work.
It is a common misconception that evolution cannot be experimentally studied in laboratories -- actually, a number of studies have been performed which indicate the existence of punctuated equilibrium in laboratory settings. In 1996 Science magazine, which is a weekly peer-reviewed journal, published an article called "Microbes hint at a mechanism behind punctuated evolution." (Mlot, 1996) The article describes an experiment performed by Lenski and Cooper, in which over 10,000 generations of e. coli were cultivated in a low-sugar solution. Over the generations, the bacteria evolved to survive best in that environment. Later generations of bacteria were larger, more fit, and could produce more offspring within the environment. Their research clearly show: "Cells tended to persist at one average size for many generations, then suddenly go through growth spurts... You can very clearly see dynamics that are punctuated, and that it's arising in this...
By using animals in research, and through animal research science learns how certain chemicals "interact with living systems"; this knowledge can be "translated into protection of humans, animals, and the environment from toxic levels of natural -- as well as man-made -- exposures (SOT, 6). Legal and professional accountability In Canada there are Research Ethics Boards (REBs) that have the power to authorize or reject funding for experiments with animals; when
The well-being of an animal, preservation of species and biological diversity is always given first priority when it comes to deciding upon the appropriateness of research to be undertaken (Lin, 2013). It reaches a point in time when some animals have to be released to the wild from the zoos. This is normally conducted in accordance with IUCN/SSC/Reintroduction Specialist group guidelines. Before the animals are released to the wild, they
The subject of the book is clearly applicable to the field of paleoanthropology because the same techniques can be applied to studies of human populations and their response to changes in the environment. In the contemporary world, the discussions in the book are also important in analyzing the nature of global warming, what might cause it, and what its consequences might be, given that global warming is one of the
Animals in captivity, for example, have often been genetically, behaviorally or anatomically manipulated in order to enhance acclimation to the new environment. Similarly, animals have been neutered, declawed or defanged to be more compatible with their human keepers. Those who are in support of captivity of animals need to revisit such earlier condoned behavior and ensure that animals receive necessary care, nutrition and exercise and live in proper caging
Animal Rights Introduction to the ESA According to Merriam-Webster's Dictionary of Law (1996) the Endangered Species Act (ESA) obligated the government to protect all animal and plant life threatened with extinction. Included in this category are endangered species, which is defined as any species "which is in danger of extinction throughout all or a significant portion of its range." Also protected are threatened species, which are defined as any species "which is
It also stands out from other leopard subspecies because of its fur that has large rosettes and a vibrant color and it can grow to approximately 7 cm long during the winter time. Due to the fact that deer and other prey species have started to fall in numbers, the leopard and the tiger have began to search for prey inside villages and farms. This gave people another reason to
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