Quotes About Population

the world of 10 billion, water experts project, the demand for water could be 50 percent higher than it is now. Where will it all come from? New supplies will not be easy to find. Few lakes and rivers are unexploited, and aquifers are being depleted. Equally difficult would be stretching existing water supplies by reducing waste and encouraging thrifty use. Adding to the pressure, climate change is shrinking glaciers and drying streams.

Alan L. Kolata excavated at Tiwanaku during the 1980s and early 1990s. He has written that by 1000 A.D. the city had a population of as much as 115,000, with another quarter million in the surrounding countryside—numbers that Paris would not reach for another five centuries.

Vogt and Osborn were also the first to bring to a wide public a belief that would become a foundation of environmental thought: consumption driven by capitalism and rising human numbers is the ultimate cause of most of the world's ecological problems, and only dramatic reductions in human fertility and economic activity will prevent a worldwide calamity.

When Columbus landed, Cook and Borah concluded, the central Mexican plateau alone had a population of 25.2 million. By contrast, Spain and Portugal together had fewer than ten million inhabitants. Central Mexico, they said, was the most densely populated place on earth, with more than twice as many people per square mile than China or India.

After Columbus everything changed. The Indian population collapsed. Clams and mussels exploded in number; they also grew larger. Game overran the land. Sir Francis Drake sailed into San Francisco's harbor in 1579 and saw a land of plenty.

If the agriculture practiced in the lower Tapajós were as intensive as in the most complex cultures in precontact North America, Woods told me, "you'd be talking something capable of supporting about 200,000 to 400,000 people"—making it at the time one of the most densely populated places in the world.

I have omitted the numbers to highlight that the basic argument is as simple as it was in Vogt's day. Stay within the limits, and people can develop freely. Go beyond the boundaries—exceed carrying capacity—and trouble will ensue.

Look at a plant in the midst of its range! Why does it not double or quadruple its numbers? We know that it can perfectly well withstand a little more heat or cold, dampness or dryness, for elsewhere it ranges into slightly hotter or colder, damper or drier districts. In this case we can clearly see that if we wish in imagination to give the plant the power of increasing in numbers, we should have to give it some advantage

For forms existing in larger numbers will always have a better chance, within any given period, of presenting further favourable variations for natural selection to seize on, than will the rarer forms which exist in lesser numbers.

Who can explain why one species ranges widely and is very numerous, and why another allied species has a narrow range and is rare? Yet these relations are of the highest importance, for they determine the present welfare, and, as I believe, the future success and modification of every inhabitant of this world.

Todo ser que durante el tiempo natural de su vida produce varios huevos o semillas, necesita sufrir destrucción durante algún período de su vida y durante alguna estación o en alguno que otro año, porque de otro modo, por el principio del aumento geométrico llegaría pronto su número a ser tan desordenadamente grande, que no habría país capaz de soportarlo.

We shall best understand the probable course of natural selection by taking the case of a country undergoing some slight physical change, for instance, of climate. The proportional numbers of its inhabitants will almost immediately undergo a change, and some species will probably become extinct.

The differences of Mr. [Patrick] Matthew's views from mine are not of much importance: he seems to consider that the world was nearly depopulated at successive periods, and then re-stocked;

La selección natural obra solamente por medio de la conservación de las variaciones que son en algún concepto ventajosas. Podemos comprender que cualquier forma representada por pocos individuos correrá mucho riesgo de quedar completamente extinguida

belirtilen çeÅŸitli engeller ve belki daha bilinmeyen baÅŸkalar?, toplumun tasas?z, bozuk ve baÅŸka bak?mlardan aÅŸa?? üyelerinin iyi insanlardan daha h?zl? çoÄŸalmas?n? önlemezse, dünya tarihinde pek s?k görüldüÄŸü gibi, ulus geriler.

the geas in question draws its power from the sum over time of the entire loyal British population's faith in the Crown since that charter was established over four centuries ago. Which adds up to something like ninety million person-centuries-worth of belief. Hence the, shall we

The central limit theorem tells us that a large sample will not typically deviate sharply from its underlying population

The central limit theorem tells us that the sample means will be distributed roughly as a normal distribution around the population mean.

All of this will be true no matter what the distribution of the underlying population looks like.

First of all, our best guess for what the mean of any sample will be is the mean of the population from which it's drawn.

The whole point of a representative sample is that it looks like the underlying population.

Specifically, the sample means will form a normal distribution around the population mean, which in this case is $70,900.

The standard deviation measures dispersion in the underlying population

Logic suggests that we should be less confident about generalizing our results to the entire adult population from a sample of 25 than from a sample of 3,000.