Mimicry In Nature Essays - Mimicry, Biology, Polymorphism, Behavior

Mimicry In Nature THE GREAT IMPOSTERS Finding good day care can certainly pose a problem these days, unless, of course, you're an African widow bird. When it comes time for a female widow bird to lay her eggs, she simply locates the nest of a nearby Estrildid finch and surreptitiously drops the eggs inside. That's the last the widow bird ever sees of her offspring. But not to worry, because the Estrildid finch will take devoted care of the abandoned birds as if they were her own. And who's to tell the difference? Though adult widow birds and Estrildid finches don't look at all alike, their eggs do. Not only that, baby widow birds are dead ringers for Estrildid finch chicks, both having the same colouration and markings. They even act and sound the same, thus ensuring that the widow bird nestlings can grow up among their alien nestmates with no risk of being rejected by their foster parents. MASTERS OF DISGUISE Things aren't always as they seem, and nowhere is this more true than in nature, where dozens of animals (and plants) spend their time masquerading as others. So clever are their disguises that you've probably never known you were being fooled by spiders impersonating ants, squirrels that look like shrews, worms copying sea anemones, and roaches imitating ladybugs. There are even animals that look like themselves, which can also be a form of impersonation. The phenomenon of mimicry, as it's called by biologists, was first noted in the mid-1800s by an English naturalist, Henry W. Bates. Watching butterflies in the forests of Brazil, Bates discovered that many members of the Peridae butterfly family did not look anything like their closest relatives. Instead they bore a striking resemblance to members of the Heliconiidae butterfly family. Upon closer inspection, Bates found that there was a major advantage in mimicking the Heliconiids. Fragile, slow-moving and brightly coloured, the Heliconiids are ideal targets for insectivorous birds. Yet, birds never touch them because they taste so bad. Imagine that you're a delicious morsel of butterfly. Wouldn't it be smart to mimic the appearance of an unpalatable Heliconiid so that no bird would bother you either? That's what Bates concluded was happening in the Brazilian jungle among the Pieridae. Today, the imitation of an inedible species by an edible one is called Batesian mimicry. Since Bates' time, scientists have unmasked hundreds of cases of mimicry in nature. It hasn't always been an easy job, either, as when an animal mimics not one, but several other species. In one species of butterfly common in India and Sri Lanka, the female appears in no less than three versions. One type resembles the male while the others resemble two entirely different species of inedible butterflies. Butterflies don't "choose" to mimic other butterflies in the same way that you might pick out a costume for a masquerade ball. True, some animals, such as the chameleon, do possess the ability to change body colour and blend in the with their surroundings. But most mimicry arises through evolutionary change. A mutant appears with characteristics similar to that of a better protected animal. This extra protection offers the mutant the opportunity to reproduce unharmed, and eventually flourish alongside the original. In the world of mimics, the ant is another frequently copied animal, though not so much by other ants as by other insects and even spiders. Stoop down to inspect an ant colony, and chances are you'll find a few interlopers that aren't really ants at all but copycat spiders (or wasps or flies). One way you might distinguish between host and guest is by counting legs: Ants have six legs while spiders have eight. Look carefully and you might see a few spiders running around on six legs while holding their other two out front like ant feelers. COPYCATS Mimicry can not only be a matter of looking alike, it can also involve acting the same. In the Philippine jungle there is a nasty little bug, the bombardier beetle. When threatened by a predator, it sticks its back end in the air, like a souped-up sports car, and lets out a blast of poisonous fluid. In the same jungle lives a cricket that is a living xerox of the bombardier beetle. When approached by a predator, the cricket will also prop up its behind -- a tactic sufficient to scare off the enemy, even though no toxic liquid squirts out. Going one step further than that is a native of the United States, the longicorn beetle, which resembles

Argument against the case an accounting standard to regulate the way in which complex financial instruments are reported in the financial statements of quoted companies essays

Argument against the case an accounting standard to regulate the way in which complex financial instruments are reported in the financial statements of quoted companies essays In this essay, I would like to start with a brief explanation about the accounting regulation and standards set for various treatments consists of gaps where the rules are vague or even incomplete. Then, I would like to give a brief introduction about the development of standards set for capital instrument, such as TR677 (ICAEW), FRED 3 and FRS 4. Next, I will go into details examining the problems found in these proposals and standard, especially FRS 4. Coming to this stage, I will divide the problems into two parts. Firstly, I will point out the inconsistency found in FRS 4 in relation to FRS 5. Secondly, I will try to deal with the practical point of view, pointing out that the FRS 4 consist of practical problems in accounting treatments for shares and debt. Finally, I will conclude that the current standard for complex capital instruments is not sufficient to solve the problems found in its accounting treatments. Hence, a more effective standard must be put forward to regulate the accounting treatment for capital instruments as it is becoming increasingly more complex. In many countries, accounting regulation is based on a system of detailed rules prescribed in standards and the law. However, rule-based systems can rarely be water-tight. There may be gaps in the rules, and places where the rules are vague or even incomplete. Of equal, if not greater significance is the fact that regulatees may develop schemes which fulfil the letter of the rules, but undermine their spirit. Regulators may find themselves constantly lagging behind the avoidance activities of the regulatees (McBarnet, 1988). In such circumstances, effective regulation breaks down. For the past ten years, the financial instruments issued by companies have become more and more complex. This has been particularly so since October 1987 which has been a period where equity issues have been difficult and companies have not wanted to increase their capital gearing. ...

EMPLOYER VS EMPLOYEE CONTRIBUTION HEALTHCARE WITH UNION WORKERS Thesis Proposal

EMPLOYER VS EMPLOYEE CONTRIBUTION HEALTHCARE WITH UNION WORKERS - Thesis Proposal Example evident that healthy humans or workers can only put in their best efforts and elevate organizations’ performance, their profits, their market share, and so on. This being the case, it is very crucial for the organizations, labor unions, and even government to adopt or come up with policies to safeguard and improve the health of the employees. Speaking of government’s role, although it is a joint federal/state system, the federal government has given the main responsibility of regulating health insurance policies regarding employees to the states. In addition, governments are encouraging organizations to come up with their own health insurance plans called employer contributed health insurance. under the McCarran-Ferguson Act. States regulate the content of health insurance policies and often require coverage of specific types of medical services or health care providersthey have The 1985 act of ‘The Consolidated Omnibus Budget Reconciliation’ required that every employer having twenty or more employees should provide nonstop access to health coverage to workers who leave their jobs. Moreover the 1996 Act of ‘Health Insurance Portability and Accountability’ (HIPA) guarantees the employees that their company authorized health insurance cover will not be revocable under any preexisting exclusions. (Patel and Rushefsky 2006). Based on this enticing factor and other necessities, the health insurance cover can be enlarged. Provide a tax credit to companies that maintain or increase the size of U.S. workforce relative to workforce outside the United States...prepare workers for retirement; provide health insurance (Sullivan, 2008). â€Å"Small businesses currently get a tax deduction for health insurance paid, and even this is limited to only an income tax deduction for the owner. Convert this deduction into a dollar-for-dollar credit. Let small businesses reduce their tax burden by how much they spend on health insurance premi ums and health savings account