How to do the continental drift dance

Ice Age: Continental Drift (2012)

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  • 20122012
  • PGPG
  • 1h 28m






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Manny, Diego, and Sid embark upon another adventure after their continent is set adrift. Using an iceberg as a ship, they encounter sea creatures and battle pirates as they explore a new wor... Read allManny, Diego, and Sid embark upon another adventure after their continent is set adrift. Using an iceberg as a ship, they encounter sea creatures and battle pirates as they explore a new world. Manny, Diego, and Sid embark upon another adventure after their continent is set adrift. Using an iceberg as a ship, they encounter sea creatures and battle pirates as they explore a new world.






    • Steve Martino
    • Michael Thurmeier
    • Michael Berg(screenplay by)
    • Jason Fuchs(screenplay by)
    • Lori Forte(story by)
  • Stars
    • Ray Romano(voice)
    • Denis Leary(voice)
    • John Leguizamo(voice)
    • Steve Martino
    • Michael Thurmeier
    • Michael Berg(screenplay by)
    • Jason Fuchs(screenplay by)
    • Lori Forte(story by)
  • Stars
    • Ray Romano(voice)
    • Denis Leary(voice)
    • John Leguizamo(voice)
  • See production, box office & company info
    • 171User reviews
    • 229Critic reviews
    • 49Metascore
  • See more at IMDbPro
    • Awards
      • 2 wins & 11 nominations


    Trailer 2:32

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    Featurette 2:12

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    Featurette 1:17

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    Promo 0:30

    Watch "The Dark Nut Rises"

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    Top cast

    Ray Romano

    • Manny
    • (voice)

    Denis Leary

    • Diego
    • (voice)

    John Leguizamo

    • Sid
    • (voice)

    Aziz Ansari

    • Squint
    • (voice)

    Joy Behar

    • Eunice
    • (voice)

    Christopher Campbell

    • Creature Siren
    • (voice)

    Alain Chabat

    • Silas
    • (voice)

    Ester Dean

    • Female Siren
    • (voice)

    Peter Dinklage

    • Captain Gutt
    • (voice)

    Karen Disher

    • Scratte
    • (voice)


    • Ethan
    • (voice)

    Jason Fricchione

    • Dumb Mammoth
    • (voice)

    Nick Frost

    • Flynn
    • (voice)

    Josh Gad

    • Louis
    • (voice)

    Ben Gleib

    • Marshall
    • (voice)

    George Jacobs

    • Beaver
    • (voice)

    Queen Latifah

    • Ellie
    • (voice)

    Jennifer Lopez

    • Shira
    • (voice)
      • Steve Martino
      • Michael Thurmeier
      • Michael Berg(screenplay by) (story by)
      • Jason Fuchs(screenplay by)
      • Lori Forte(story by)
    • All cast & crew
    • Production, box office & more at IMDbPro

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    Did you know

    • Quotes

      Diego: I don't know whats wrong with me: I can't eat, can't sleep; I think I'm coming down with something.

      Manny: [chuckles] I know what you've got: the "L" word.

      Sid: Yeah, leprosy!

      Manny: No, Sid, no. It's four letters, starts with "L", ends with "E".

      Sid: Ah, lice!

      Manny: No. Diego, my friend, is in love.

    User reviews171


    Featured review



    Entertaining, but not so much as before

    I have always liked the Ice Age series up to the third one. In fact, this is the first time that I thought I would watch it in theater rather than getting a DVD later. The 3D was spectacular in terms of visual appearance, but I would not rate it as good as the previous Ice Age movies.

    The plot during this adventure is short and simple. There's no surprises, and everything is pretty much along the line of a typical friendship/family/hero type story. The whole story took place in 3, 4 "in-movie" days, much shorter than the previous ones which had a constant string of events. By the end of this movie, I couldn't believe the story's over. Not a lot happened before the villains are apprehended and the world returns to peace and harmony, as in any of the Ice Age movies. However, this probably means their target audience are younger than the ones before. I guess this is the biggest drag down for fans who have been watching since the first one.

    They also did a sub-par job in the music. Despite having no improvement in quality, they recycled music from the second movie in the series, "the Meltdown". I bought the soundtracks after watching that movie thinking it was spectacular. After listening to it for years now, I could virtually name the tracks as they come up in the Continental Drift. From the title sequence to the Ending, pretty much everything without a vocal voice was identical to something I've heard before. It feels like they just copied and pasted from before - The soundtracks are awesome, but when it's used once too many, it just doesn't have the same impact anymore.

    I still gave this movie a 6 because of, well, what Fox and Blue Sky has always been best at. The vivid colors and the "just right" graphical presentation is sure a feast on the eyes. And don't forget about Scrat, who's never involved but just somehow miraculously leads the story. This movie is definitely great for fun, there are many (supposedly deliberate) punch lines. Although some puns fail when I go "huh? that's lame", I can feel that they are trying to make it as funny as possible. I'd say that they are making this movie more like a feature-length, high quality TV cartoon special rather than a real theatrical movie. There's just not that much thrill to it.

    The addition of the new characters seems only to provide a villain to the storyline. There doesn't seem to be much careful consideration - from what I see, it's perfectly fine to replace any of them with another animal or personality and the story stays valid. The characters' specialties just do not come together and contribute to the story, another reason why it feels like the story was written without the context of the movie. Not even the prolonged characters like Manny, Diego, Sid and Peaches.

    Bottom line: This movie is mediocre. It could do as a really nice cartoon, but it lacks the punch in the planning.



    • ashfox
    • Nov 10, 2012

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    • Is there any extra scene during or after the end credits?


    • Release date
      • July 13, 2012 (United States)
      • United States
      • Official site
      • Official site (Spain)
      • English
    • Also known as
      • Ice Age 4: Continental Drift
    • Production companies
      • Blue Sky Studios
      • FortyFour Studios
      • Twentieth Century Fox Animation
    • See more company credits at IMDbPro

    Box office

      • $95,000,000 (estimated)
      • $161,321,843
      • $46,629,259
      • Jul 15, 2012
      • $877,244,782
    See detailed box office info on IMDbPro

    Technical specs

    • 1 hour 28 minutes

      • SDDS
      • Dolby
      • Datasat
      • Dolby Atmos
      • Auro 11. 1
      • Dolby Surround 7.1
      • 2.35 : 1

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    The dancing Earth: continental drift

    The pillars of Pozzuoli: the frontipiece of Charles Lyell Principles of Geology (1831)

    In hindsight, continental drift should have been obvious. That the Earth moves up and down had been known for centuries, shown by the layered beaches of Sweden, the seashells of the Himalayas, or the sinking harbours of the Med. The drowned and resurfaced Pillars of Pozzuoli became famous as the frontipiece of Charles Lyell’s opus magnus, Principles of Geology (1833). If up and down is possible, why not sideways? The close relation between the coasts of Africa and South America was obvious to everyone. But science, ruled by conservative geologists, blocked this obvious step.

    Don’t judge these senior scientists too harshly. The physics of continental drift is still far from straightforward. There was no known source of sufficient energy within the Earth. Convection in solid rock was unimaginable. The data spoke loudly, but in an unintelligible language. It needed translating and interpreting. Science stuck to things it understood. It kept its feet firmly on solid ground.

    Only in the 1960’s did the tide change. The mid-oceanic ridges had been discovered, and the oceanic crust dated. The ages left no doubt that new crust was being created. Even the most conservative geologists could no longer deny the flood of evidence. Continental drift became accepted, 200 years delayed. Let it move.

    The 15 major plates. Source: wikipedia

    The main mid-oceanic spreading ridges

    We now know of 15 major plates, each moving independently from the others. Most of them contain a continent (the North America plate covers more than one) but some are purely oceanic. In between the plates are the spreading ridges and subduction regions. All active spreading ridges are oceanic, even if some (such as the Red Sea spreading ridge) started on land. The answer to how continental drift works lies underneath the sea.

    See it move

    The increasing distance between telescopes in Germany and the US

    The spreading rate of a typical mid-oceanic ridge is 5 cm/yr. As every book on the topic says, it is the rate at which finger nails grow. Nowadays we can measure this directly. Radio telescopes measure the exact direction to distant galaxies. Over the years, this direction changes as the ground underneath them moves. Compare two telescopes, and you can measure how the distance between them changes. This is accurate to millimeters. The figure shows the increasing width of the Atlantic, measured between two telescopes. You can see the slow, smooth movement, with an annual fluctuation. The rate of increase seems slow, but this is because the baseline crosses the spreading ridge at an angle and does not see the full movement.

    But what is it that makes the continents move? The main action is clearly in the oceanic plates. But what force can make the surface of the Earth drift? Physics tells us that there are four different processes at work. In increasing order of importance, these are:

    Magma injection The magma injected into a spreading ridge can push the two sides apart, and set the plates in motion.

    Convection currents The convection currents in the mantle can themselves induce horizontal motion, because upwelling and downwelling occurs in different regions. The flow in the mantle can drag the crust along.

    Gravity Spreading ridges are pushed up by several kilometers. Subduction occurs in deep trenches. Gravity causes material to move from high (spreading ridge) to low (the trench). This is called ‘ridge pull’. (It is also called ‘ridge push’ but this is misleading as there is no push from behind. )

    Subducting plates As the slab sinks, it pulls the rest of the plate with it. This is called ‘trench pull’ or ‘slab pull’.

    Slab pull is now considered the most important effect, followed by ridge pull. Horizontal convection currents in the mantle would affect the continents most, since they have deep keels sticking into the mantle, but this is not observed. Instead the continents seem to respond mainly to the oceanic crust. Ridge pull is important, but magma injection by the rising mantle, which would seem to be the most obvious way to drive plates apart, does not work as a force.

    Spreading ridges and plumes

    Mantle plumes are different from spreading ridges. They produce ‘hot spots’, seen in places such as Hawaii. They are deep, rising, convective cells, which reach to the surface and by their heat, push it up. Magma forms, and a tall volcano appears. It grows tall not just from the lava deposited on top, but also from the push from below. Once the volcano drifts away from the hot spot (the curse of continental drift: it is hard to stay in one place), the mountain quickly sinks again. This will be the fate of Hawaii. Hot spots do not form spreading ridges: Hawaii did not break the Pacific plate. This shows how ineffective magma injection is in setting plates in motion. However, sometimes a hot spot does break a continent, forming a triple junction which can develop into a new spreading centre. Africa has been susceptible to this. But it is rare, as shown by the fact that neither the Yellowstone hotspot nor the Deccan Traps broke their host continent.

    There are cases where a hot spot coincides with an existing spreading ridge. Iceland is one example, the Azores and Amsterdam/St Paul are others. Are these accidental? If so, the hot spot should rather quickly drift away from the spreading ridge. But this is not seen. Iceland is at least 20 million years old, and it is still largely centred on the continental divide. The reason may be gravity pull. The hot spot pushes a region up. Gravity pull begins to act. If there already was a plate break nearby, the plate may now begin to break at this point, letting the old break nearby stop and heal. In this way, a hot spot can pull a spreading ridge along, at least for a while.

    Hot spot volcanoes are common on Mars and Venus, as they are on Earth. But spreading ridges and continental drift only occur on Earth. We are unique.



    The mantle extends from 100 km depth to almost 3000 km. It is solid material, not liquid, although it can move around as well as up and down. If this seems strange, think how sand can do the same. The mantle rock changes at a depth of 410 km, and again at 660 km. The higher one corresponds with a change from olivine to spinel, and the lower one a change to perovskite.

    Subducting plates are cooler than the surrounding rock, and go through the first phase change a bit earlier. This increases their density while the surrounding rock is still of lower density olivine. This increases the downward pull on the subducting slab. Most of the slab-pull force comes from this phase change. Subducted plates often, but not always, stay above the deeper discontinuity: there is a ‘plate graveyard’ at this depth.

    The phase changes can stop convecting cells from rising. Only strong convective cells break through them from below. If a cell gets stopped, it develops a broad plume head, creating a larger region of warmer material. So there may be two layers of convection in the mantle, separated by the discontinuity, with only a few hot, deep plumes being able to rise through both.


    What causes the convection in the mantle? Convection forms when there is a large temperature gradient. The hot material at the bottom has lower density, and the buoyancy causes it to rise. Convection can be triggered either by heat from below, or cooling at the top. Mantle convection probably has both effects. The heat from below can come from the core (from the slow solidification of the inner core), or from radioactive elements in the mantle itself. Cooling at the top can come from subducting plates, or from water cooling of oceanic plates. The convection can be deep, from the core, or be in the upper mantle only, driven from the 410km phase discontinuity. Underneath continents, sideways convection can occur, from hot regions near the centre of the continents (where mantle heat is trapped) to the cooler edges. Perhaps these also happen from the warm mid-oceanic ridges.


    Let’s try to put some numbers in.

    The total length of the spreading ridges on Earth is a staggering 40,000 km. The oceanic crust is about 8 km thick. For an average spreading rate of 5 cm/yr, we need to create 16 billion cubic meter of basalt every year (length times width times thickness). The density of basalt is 2400 kg/m3, so that 38 trillion kg of basalt is added to the oceanic plates each year. Obviously, the same amount must be going down in the subduction zones each year, to keep the Earth in net balance.

    The new basalt coming up from the mantle is hot. It cooled down while coming up but it is still hotter than the normal oceanic crust. Because it is warmer, it has lower density. This buoyancy pushes the mid-oceanic ridges up, to 3-4 kilometer above the ocean floor.

    Let’s assume that basalt within the spreading ridge in the ocean has a temperature of perhaps 1300 C. As it moves away from the ridge, pulled in by slab-pull and by gravity, it cools and grows denser. Let’s assume that once it reaches 800 C, it begins to subduct. (The numbers are approximate but not far off. Obviously the surface is much cooler and these numbers are for the bottom of the crust.) The heat capacity of basalt is 0.84 kJ/(kg K): in other words, to cool 1 kilogram of rock by 1 degree centigrade releases 840 Joule of energy. Cooling by 500 degree centigrade releases 0.4MJ per kg of basalt, between upwelling and subduction. This is a lot of energy. For 1 square meter of ocean floor, and 8 km of crustal depth, the total energy to be lost is 8 TeraJoule (8 x 1012 J).

    Rock insulates very well and it gives up this heat very reluctantly. The k value of basalt is 1.69 W/ (m K), which means that for each degree of temperature difference, a 1 meter thick rock layer lets out 1.69 W per square meter surface area. A 1 kilometer thick rock reduces the leakage to 1.69 milli-Watt. So how long does it take oceanic crust to cool down from 1300C to 800C? Take the average thickness as 4 km, and the temperature difference with the surface 800 C (the deep ocean being 4C). A quick calculation shows that the ocean floor near the ridge will radiate about 0.34 W per square meter.

    At this rate, the cooling will take a million years. This sounds like a lot but in geological terms it is fast. However, although the initial cooling is fast, it slows down a lot later, when the temperature difference is much less. Cooling continues for typically 100 million years.

    As the rock cools, it contracts and becomes denser, and the ocean floor begins to sink because of the contracting rock: the sea grows deeper over time. The approximate relation is that the depth of the ocean is 2. 5km, plus 0.35 times the square root of the age in million of years. At zero age (i.e. the spreading ridge) the depth is 2.5 km. After 1 million years it is 2.85 km, and after 100 million years, the ocean is about 6km deep. After this it increases only very slowly. Therefore the oceans are least deep at the spreading ridge, and after about 1 million years, when the floor has moved by about 50km, it rapidly becomes deeper. The spreading ridge is therefore typically 100 km across.

    From, copyright San Jose State University

    The plate is actually much thicker where it forms, and thins further out as the movement speeds up. Eventually the oceanic crust cools so far that it become denser than the pressured mantle (aestenosphere, to be precise) below. Once this happens, the ocean plate begins to sink, like blobs in an old-fashioned lava lamp. Let subduction begins.

    Subduction reheats the sinking plate. It comes in an area where temperatures are much higher and sucks up this heat. The sinking and the higher pressure itself also generate heat. After 100 million years of solitude, the plate can get cozy again in the homely warmth of the upper mantle, returning to its Macondo, and dissolve in the plate graveyard.


    Volcanoes occur in two part of this cycle. The spreading ridge itself is effectively a 40,000 km long volcanic rift, producing gigantic amounts of basalt. Images of the ocean floor clearly show a rift, situated in the centre of the ridge. Most of the basalt is injected far below the surface; only a small fraction is erupted on the surface. Sometimes a ridge becomes overactive and floods the sea floor with thick layers of basalt, as a LIP (or Large Igneous Province). The largest such event known is Ojong Java Nui, which covered as much as 1.2% of the Earth, and was emplaced below the sea 125 million years ago. Ridge volcanic activity is well behaved, with stuff oozing out. The pressure of kilometers of seawater above is too high to allow for explosive ejection. These are the only types of volcanic eruptions which attract rather than destroy life.

    Giant tube worms and a scary-looking
    spider crab near deep sea hydrothermal vents.,

    This volcanic activity quickly dies down as the plate cools, and the plate becomes inert apart from the occasional hot spot or warm region it traverses on its journey. Where this happens, a volcanic island may form. All deep sea islands (apart from Australia) are volcanic in origin.

    The second phase of volcanic activity occurs during subduction. The oceanic plate is solid. As it subducts, both temperature and pressure rise and a race begins. The melting point increases with pressure. If the temperature increases faster than the pressure, a bit of melting will begin. In practice, this may happen at certain depths, and the plate becomes solid again as it goes deeper still. The subducting plate probably contains water (the upper range of the oceanic plate becomes pretty wet, as you may imagine) and this lowers the melting temperature. Once rock melts, it becomes less dense and buoyancy pushes it upwards. The result is volcanic.

    Let the dance commence

    Therefore, continental drift begins with a cool surface slab descending into the mantle (‘the enemy’s gate is down’). This pulls oceanic crust with it, and some distance away the crust tears in response. The tear creates a gap, and the underlying mantle floats up to fill the gap, forming a new hot surface. Below, more material comes up from the mantle, carrying its heat with it. All activity happens below the sea. The continents are floating on the oceanic crust, passive and driven by the whim of the oceans.

    Spreading ridges thus form by tearing crust asunder. Convective mantle cell are not needed. The mantle does have convective cells, forming hot spot volcanoes. As a rule, hot spot volcanoes have magma that comes from very deep in the mantle, pristine material that has not been to the surface before. Mid oceanic ridges have magma from shallow mantle sources, that has been through several cycles, lacking some elements that ended up in the continents. Subduction takes the plates down to the graveyard, but only rarely to the deeper mantle. The shallow mantle is thoroughly processed, mixed, baked, cooled and wetted. The deeper mantle, source of the hot spots, has had a more sheltered life.

    What we see on the surface is the stately dance of the continents. Now we know that this is just a veneer, driven by the far more rousing dance of the oceans which pulls and pushes the continents along. In turn, this is part of a lively upper mantle. Our solid ground is floating on a sea of trouble. There is danger in the dance.

    Geolurking, bless him, pointed out the real origin of continental drift

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    What is drift? Types of Drift

    Currently, the meaning of the word "drift" can be applied in several areas of science at once. This term extends to geography, and to optics, and to anatomy, and to many other areas of activity.

    Continental drift

    In 1912, the German scientist Alfred Wegener proposed a heuristic theory of the endless movement of continental masses. The geologist made such conclusions based on his own observations and discoveries. What is continental drift? Wegener assumed that the continents are in constant motion, but the speed is so small that it cannot be felt. At the beginning of the 20th century, such a report caused a lot of criticism and ridicule from the scientific world.

    It is worth noting that continental drift was discovered long before the German geologist. In the 1620s, the notorious enthusiast Francis Bacon noted in his handwritten writings some coincidences in the outline of the coasts of America and Africa. Based on his notes, decades later, the idea of ​​​​moving the continents was put forward by the Frenchman Franco Plake, and then by the German Theodor Lilienthal. In 1858, the American theologian Antonio Snyder proposed a more radical theory that, as the Earth cooled, the surface could not withstand the pressure and broke apart.

    Continental drift has not been proven for a long time. In most of Europe and the US, this theory is still rejected. Nevertheless, in the early 1960s, Soviet scientists came to the conclusion that Wegener's judgments were reliable. In turn, the famous Russian geologists M. Usov and S. Obruchev continued to defend the concept of fixism.

    The theory of continental drift

    At the beginning of the 20th century, Alfred Wegener traveled around the world in order to understand the essence and origins of all life on the planet. Based on numerous data from expeditions, the German geologist determined that all continents have a similar structural structure. Moreover, the scientist proved the commonality of the fossil fauna and flora of the continents in the past. Parallels could also be drawn in terms of climatic zones.

    According to Wegener, a granite layer first appeared on the surface of the planet. Over time, the outgrowths of the rock were concentrated into a large pra-continent called Pangea. This formation dates back to 500 million years BC. It was then that a single pra-ocean was formed. As a result of tectonic movements, Pangea began to split into small parts. This is how continental drift appeared.

    The movement of the continents is achieved by the centrifugal forces of the Earth's rotation. An important factor is the attraction of the Sun and the Moon. Due to this, North America, and then Africa, moved away from Eurasia. The giant crevice was filled by the Atlantic Ocean. The result of the split of Pangea was the Andes and Cordillera mountain ranges.

    As a result of the drift, the continents of Africa and Europe collided with each other, forming the Alps, the Himalayas, the Carpathians and other mountain ranges. According to Wegener's hypothesis, the main points of rotation of the continents were the Earth's poles.

    Ice Drift

    It is no secret that frozen masses of water move through the seas and oceans due to the internal current. But what is ice drift? This is by no means free movement on the water surface. In this case, this is the movement of icebergs in the ocean or sea under the influence of winds and various currents.

    Most of the ice drifts in the Arctic, where research never stops. Such movements are represented mainly by anticyclonic movement, in other words, clockwise. As a result of such a cycle, ice leaves the Arctic Ocean to the shores of Greenland in three streams. On such a path, a small iceberg will need from 1 to 5 years, depending on the initial breakaway point. The trajectory of movement depends on the Greenland current.

    The first to observe a unique phenomenon was the scientist F. Nansen back in 1893 years old Then the ship "Fram" drifted from the Novosibirsk coast to the Greenland Sea. Nansen tracked the relationship between the characteristics of ice throughout the entire 3-year journey of the expedition. As a result, the scientist identified two important rules: the iceberg drift speed is approximately 2% of the accompanying wind speed, and the direction of movement lies 30 degrees to the right of the current. Nansen's data was subsequently confirmed by the Soviet professor Vladimir Vize.

    Baric ice drift

    This is a unique natural phenomenon since 19From 13 to 1940, dozens of expeditions studied in the waters of Greenland, and each time scientists agreed that Nansen was right in his works and guesses. In the late 1930s, the Soviet Union launched a whole network of weather stations into the Arctic. The project was headed by the scientist N. Zubov.

    Based on the data obtained, he and his team were able to identify a pattern of drift that occurs along the isobars. As it turned out, the current in Greenland waters is extremely weak, but the wind is very strong. It was he who drove the ice floes to the shores of large islands. This is how baric drift was discovered. It followed two rules:

    1. Ice and isobar directions coincide. At the same time, the pressure is significantly increased in the right area.

    2. The speed of movement is inversely proportional to the distance between the isobars.

    As for the 30 degree angle, this deflection is due to the Coriolis force and friction.

    Gene drift: definition

    Millions of automatic processes take place in the human body at the cellular level. One of the most interesting and unique of them is genetic drift. This is perhaps the only mechanism that is caused by random static phenomena. So what is genetic drift? This is a chaotic change in the frequency of alleles of genes, that is, population variations.

    The mechanism of the phenomenon lies in the reproduction procedure, as a result of which a huge number of germ cells called gametes are formed. These cells are not capable of forming zygotes, but there are rare exceptions. It is from them that unique species are formed in the population. It should be noted that the shift in the range of allele frequencies is possible only relative to one previous generation.

    Drift leads to the evolution of species in local populations. It is important to understand that such a change in frequencies occurs independently of any factors.

    Genetic drift: population waves

    This process in no way affects the abundance of species, since booms are always followed by recessions. Many scientists are still wondering what is genetic drift in relation to evolution. The Russian scientist S. Chetverikov tried to answer this in his research. He drew attention to the regular fluctuations in the number of populations. During the experiments, it was revealed that these processes play a decisive role in the evolution of all life on the planet. Fluctuations in numbers are called population waves.

    The human genetic structure is built in such a way that at the right time to produce offspring - a new individual of a similar species. In animals and plants, population waves depend on a territorial feature. Only species with the original genetic code can appear in a certain zone. Nevertheless, alleles are responsible for evolution in fauna and flora.

    Gene drift: molecular evolution

    The end result of the phenomenon will be the complete disappearance of one allele from the population and the fixation of another in it. The higher the level of genetic drift, the faster the molecular evolution of the species. Studies show that the probability of fixing a moving allele is equal to the frequency of the population.

    It is noteworthy that each such gene molecule arose sometime as a result of a mutation. Evolutionary leaps occur at a frequency of about 10-5 per gene/gamete. It is logical to assume that the lower the population level, the lower the probability of a new mutation.

    Nevertheless, many scientists believe that the degree of evolution does not depend on the size of the species and the number of drifting genes. American researchers Polling and Zuckerkandl found that neutral alleles move at a constant speed. This applies to any species.

    Electron drift

    This process is the movement of charged particles under the influence of a static field. Movement can be erratic and regular. It all depends on the conductivity of the electric field.

    The drift of particles in gases and metals under the influence of current is determined by thermal motion. In this case, it will not be possible to predict the speed and direction of movement. The fact is that the thermal action does not form a single macroscopic flow of charged particles. Here, the connection of electrons with the field is characterized by the intensity and density of the medium. In plasma, the particles are under the action of a magnetic field, so the movement will be uniform and regular.

    The drift velocity of charges in an electric field is much higher than that of ions. This is due to the stronger momentum of the medium.

    DC Drift

    There is one major problem with the FET amplifier - spontaneous voltage drop. This phenomenon is called zero drift. As a result of turning off the current at the output of the amplifier, the value of the indicator drops to the initial value. Zero drift is most often observed in the absence of an input signal.

    The reasons for this shutdown can be:

    - power supply failure;
    - instability of resistors or transistors;
    - low-frequency noise;
    - high ambient temperature;
    - interference or interference.

    Galvanic coupling between stages can become the most rare and complex consequence of a current cut in a UPT. It quickly transmits signal changes, so the instability at the input is almost impossible to trace.

    To neutralize zero drift, you can use thermal compensating components, deep feedback, DC converters, a state detection mechanism. It would be useful to change the balance scheme of the UPT.

    Eye drift

    This process is caused by smooth slow displacement of the eyeball. In other words, this is an involuntary fixation of the central part of the retina on an object. The logical question is what is eye drift and what are its causes.

    To answer it, you need to understand that the human retina has 3 types of movements that are not even felt: constant tremor, jerky fixation and smooth movement. The first state is the norm. The frequency of contraction of the eye muscles is up to 80 Hz. The second state is also within the normal range. The mechanism is controlled by a sudden reaction. The third state is allowed only together with the first two, but not separately. Its cause may be the denial of the feedback mechanism by the retina.

    Ship drifting

    Vessel drifting off course is most often caused by strong winds. The main characteristic of such a drift is the angle between the lines of the true and false direction of the route.

    The drift of the boat can be influenced by the current. Drift also denotes the displacement in the “at anchor” position, when the load creeps along the bottom.

    The most dangerous consequence of such a drift is the possibility of the vessel entering rocks or shallow water. To avoid such a situation, it is necessary to direct the ship with its bow into the wind.

    90,000 Ice period with the Cinema Cinema -
    1. News

    2 July 27, 2012 16:17

    July 12 — Ice Age 4: Continental Drift in 3D.

    The event will be opened by a show program with the participation of Alexei Koshcheev dedicated to the film premiere. Each guest will be able to participate in exciting competitions and win tickets to the premiere and other interesting prizes. Also, the guests of the holiday will have the opportunity to make a fancy face painting and take pictures with their favorite characters.

    The culmination of the evening will be the presentation of a new life-size puppet - the character of the cartoon beloved by everyone.

    Which of the heroes of the "Ice Age" from now on will please the residents of Kirov and the guests of the "Smena" cinema, the organizers still keep a secret.

    At the end of the event, all guests will be able to watch the long-awaited cartoon Ice Age 4: Continental Drift in 3D. Entrance to the festival is absolutely free!


    Red color of the epoch: "The Art of the Land of the Soviets" is shown in Kirov (0+)

    The new exhibition project of the Vyatka Art Museum consists of more than 150 works.


    In Kirov there will be a competition in sports ballroom dancing "Let's dance" (0+)

    On December 11, dancers from more than 40 Russian dance clubs will gather in the regional center.

    Culture | Society

    The ATOM+ festival in Kirov will tell how to promote science in schools (18+)

    The event will take place on December 5th. What awaits the listeners?

    Culture | Poster | In their free time

    Kirov will host an inclusive laboratory for young directors "Special Theatre"

    Directors from Moscow, St. Petersburg and Kirov will create sketch productions and performances in a few days.

    Culture Georgy Malkov, producer of the film, and DJ Groove, composer of the music for the film.

    Learn more