.... can affect both a population and an ecosystem. A pollutant on a population level can be either non-target or target. Target effects are those that can kill off the entire population. Non-target effects are those that effects a significant number of individuals and spreads over to other individuals, such is the case when crop dusters spread herbicides, insecticides. Next we look at population damage by a pollutant, which in turn has a detrimental effect on the ecosystem in several ways. First, by the killing of an entire population by a pollutant, it offsets the food chain .....

.... would increase significantly"(Elmer- Dewitt 38). The experiment the scientists performed is the equivalent of a mother producing twins. The process has been practiced and almost perfected in livestock for the past ten years, and some scientists believe that it seems only logical that it would be the next step in in-vitro fertilization. The procedure was remarkably simple. Hall and Stillman "selected embryos that were abnormal because they came from eggs that had been fertilized by more than one sperm" (Elmer-Dewitt 38), because the embryos were defective, it would ha .....

.... In Jane Goodall's, May 1979 article in the National Geographic called "Life and Death at Gombe" it reveals the first time that chimpanzees who were always perceived to be playful, gentle monkeys, could suddenly become dangerous killers. "I knew that some of our chimpanzees, so gentle for the most part, could on occasion become savage killers, ruthless cannibals, and that they had their own form of primitive warfare."(Goodall, 1979:594) To try and explain this ruthless behavior it is necessary to first analyze their social upbringing and unique lifestyle. The Chimp .....

.... lack of exercise). The difference between primary and secondary hypertension is that we know the causes of secondary hypertension. Usually, the causes of secondary hypertension include renal artery stenosis (or other cause of increased plasma renin), renal parenchymal disease (glomerulonephritis, diabetic nephropathy, polycystic disease, obstructive uropathy), drugs (oral contraceptives, steroids), and increased levels of catecholamines (pheochromocytoma), glucocorticoids (Cushing's disease), or mineralcorticoids. Symptoms Hypertension is referred to as "the silent .....

.... claimed that cannabis destroys brain cells. However, several other studies found no structural or neurochemical atrophy in the brain at all. Furthermore, it should be noted that Heath's work was sharply criticized for avoiding safeguards of bias and reporting "changes" that occur normally in the mammalian brain. Wu et al. found a correlation between cannabis use and low sperm counts in human males. This is misleading because a decrease in sperm count has not been shown to have a negative effect on fertility and because the sperm count returns to normal after cannabis use has .....

.... cm to 1.5 m long, and not more than 20 cm below the surface. Each burrow has a large area at the end for the nest which was composed of shredded grass. These nests were used for young or as a resting place for groups of adult shrews. Compared to most types of shrews, the least shrew is sociable, and several may be kept together in captivity without conflict. They sleep together and help eachother to some degree in digging tunnels and finding food. One nest found in December in Texas contained a dozen shrews that seemed to be staying there for the winter; another examined n .....

.... States 85 to 90 percent of all cases are related to smoking. Cigarette smoking is the main cause of (Scientific American, “”). Second-hand smoke, inhaled by non-smokers, increases a person’s chance of acquiring (Beau Halton). Men who smoke increase their chance of dying from about 23 times and women increase their chances 13 times (“ Awareness Campaign,” 3/23/99). However, may also be caused by long term exposure to radon, a naturally present radioactive gas (SIRS, “What is Cancer?”). The residue of burned petroleum and coal .....

.... and it was Darwin himself who said that Lamarck was the first man whose conclusions on evolution brought about excitement and attention. He was the one who showed law in organic and inorganic species evolution. As it turned out, the work of Lamarck was quite influential on Darwin. Lamarck's views on inheritance of characteristics can be seen in Darwin's accounts of natural selection. When Lamarck wrote of transmutation, Darwin followed with his beliefs of the mutability of species. As well, Darwin had used Lamarck's ideas on use and disuse of organs. Lamarck was not the great .....