Sentences with phrase «occurred over thousands of years»

Looking forward, climate researchers have already predicted a rise in global temperatures to occur over the course of centuries, not the relatively gradual warming which occurred over thousands of years in the case Paleocene - Eocene Thermal Maximum.

More importantly, that earlier warming occurred over thousands of years.

Although a proportion of the ROH observed in both English bulldog and Standard Poodle can be attributed to natural selection pressures occurring over thousands of years [33, 34], the differences in ROH size and number are better explained by the comparative changes in outward appearance.

A process that occurs over thousands of years after the ice melts.

Not exact matches

davidhmittelberg, so it has never occurred to you that after thousands of micro-evolutionary changes, over millions or billions of years, that you might end up with a creature that can no longer successfully mate with its ancestors?

«There must have been regional climate and chemical conditions that varied in time and space,» he says, adding that this would occur as the tilt of Mars's spin axis changed over tens of thousands of years, a wobble caused by the lack of a massive moon to stabilise the planet.

Multiple waves of human settlement in the Caribbean occurred over the past six to seven thousand years.

Carbon - 14 is a rare, but naturally occurring, radioactive type of carbon that decays over thousands of years.

«Though very rarefied by Earth standards, these interstellar clouds are the sites of complex chemical reactions that occur over hundreds - of - thousands or millions of years,» said Jan M. Hollis of the NASA Goddard Space Flight Center in Greenbelt, Md. «Over time, more and more complex molecules can be formed in these cloover hundreds - of - thousands or millions of years,» said Jan M. Hollis of the NASA Goddard Space Flight Center in Greenbelt, Md. «Over time, more and more complex molecules can be formed in these cloOver time, more and more complex molecules can be formed in these clouds.

Processes that have historically altered the face of the planet, like cycles in the Earth's orbit around the Sun or shifts in continental tectonic plates, occur over tens of thousands to millions of years.

Evolution is typically thought of as a process that occurs over hundreds or thousands of years, but this doesn't mean that we can not observe genetic changes as they develop.

How did gluten, a naturally - occurring protein found in wheat, barley and rye — sources of nutrition for people over thousands of years, become so unhealthy?

The aforementioned studies are only several of thousands done over the years to prove that testosterone and HGH injections through medically supervised treatment have a definite effect on health related issues that occur because of declining levels of human growth hormones and testosterone.

With over 400,000 structure fires that occur throughout the country every year, there's always a possibility that any resident could lose their personal property worth thousands of dollars at any moment.

I have seen many more cases of lung cancer among nonsmokers than smokers in the thousands of patients I have cared for over the past thirty years, but that doesn't negate the studies done on the subject that show only about 15 % of lung cancer cases occur in nonsmokers.

MalcolmT says: «Nick @ 20 Previous climate changes occurred over a time scale of hundreds or thousands of years.

Re glacial cycle CO2 and temp correlation, it is useful to remember that the timescale of that record is 100's of thousands of years, where as the CO2 rise today has occurred over ~ 100.

Rather, excess CO2 returns toward baseline at a multitude a different rates, with chemical equilibration in the ocean occurring over decades (depending on depth), ocean carbonate buffering through sediment dissolution requiring centuries to millennia, and eventual restoration of carbonate sediment levels by terrestrial weathering occurring over hundreds of thousands of years — a long «tail» that can account for as much as 20 to 40 percent of CO2 excess in the estimates described by David Archer et al in CO2 Atmospheric Lifetimes.

Reality: Whilst there are many areas of interesting research with respect to the glacial - interglacial cycles of the Quaternary, we have a good understanding of the primary drivers i.e. orbital variations occurring over cycles of tens of thousands of years.

Glacial cycles (ice ages) are set in motion by (1) periodic wobbles in the tilt of the Earth's rotation, (2) changes in the tilt of its axis, and (3) the shape of its orbit occurring over tens of thousands of years.

This change in sea level occurred in the context of different orbital forcing and with high latitude surface temperature, averaged over several thousand years, at least 2 °C warmer than present.

Problem being that the huge influx of anthropogenic CO2 has pretty much overwhelmed this negative feedback process as it occurs over thousands and tens of thousands of years, and we'll have doubled CO2 in just a few hundred years.

Only one of the past «Big Five» mass extinctions (the dinosaur extinction event at the end of the Cretaceous) is thought to have occurred as rapidly as would be the case if currently observed extinctions rates were to continue at their present high rate (Alvarez et al., 1980; Barnosky et al., 2011; Robertson et al., 2004; Schulte et al., 2010), but the minimal span of time over which past mass extinctions actually took place is impossible to determine, because geological dating typically has error bars of tens of thousands to hundreds of thousands of years.

The Earth is entering a period of climate change that will likely be faster than what has occurred naturally over the last thousand years, according to a new study by scientists at PNNL.

Surely what matters are (i) the effects on future generations over tens of thousands of years if runaway warming of several C is allowed to occur (ii) loss of biodiversity forever (iii) effects on developing world in our lifetime as well as beyond.

The rise of CO2 that led to this dramatic acidification occurred during the Paleocene - Eocene Thermal Maximum (PETM), a period when global temperatures rose by around 5 °C over several thousand years and one of the largest - ever mass extinctions in the deep ocean occurred.

However, the Big Five occurred over periods of hundreds of thousands to millions of years, so Barnosky and colleagues also attempted to determine how long it might take us to reach mass extinction levels (75 % of species extinct).

To answer this question, the scientists examined a hypothetical scenario in which the Big Five extinctions occurred suddenly, such that all of the species went extinct over just 500 years rather than over hundreds of thousands to millions of years.

Both solutions will occur because the power of the news media and of the internet, interacting, will quickly make widely known these types of information, the cumulative effect of which will force governments and the courts to act: (1) the situations of the thousands of people whose lives have been ruined because they could not obtain the help of a lawyer; (2) the statistics as to the increasing percentages of litigants who are unrepresented and clogging the courts, causing judges to provide more public warnings; (3) the large fees that some lawyers charge; (4) increasing numbers of people being denied Legal Aid and court - appointed lawyers; (5) the many years that law societies have been unsuccessful in coping with this problem which continues to grow worse; (6) people prosecuted for «the unauthorized practice of law» because they tried to help others desperately in need of a lawyer whom they couldn't afford to hire; (7) that there is no truly effective advertising creating competition among law firms that could cause them to lower their fees; (8) that law societies are too comfortably protected by their monopoly over the provision of legal services, which is why they might block the expansion of the paralegal profession, and haven't effectively innovated with electronic technology and new infrastructure so as to be able to solve this problem; (9) that when members of the public access the law society website they don't see any reference to the problem that can assure them that something effective is being done and, (10) in order for the rule of law, the Canadian Charter of Rights and Freedoms, and the whole of Canada's constitution be able to operate effectively and command sufficient respect, the majority of the population must be able to obtain a lawyer at reasonable cost.