Drifting

The breakup of Pangea started roughly 200 million years ago.

Sea floor spreading is the process that creates new oceanic crust at mid-ocean ridges, which are underwater mountain ranges. As the new crust forms, it moves away from the ridge, pushing the existing ocean floor aside. This movement is what allows continents to drift apart from each other, as the forces generated by sea floor spreading contribute to the overall movement of tectonic plates.

Alfred Wegener's theory of continental drift was important because it proposed that continents were once joined together in a single supercontinent called Pangaea. This theory laid the foundation for the modern theory of plate tectonics, which explains the movement of Earth's lithospheric plates over time. Wegener's ideas revolutionized our understanding of Earth's geology and the processes that shape its surface.

Fossils found on different continents that were once part of a single landmass supported Alfred Wegener's theory of continental drift. These fossils, along with matching rock formations, ancient climate evidence, and geological features, helped to provide evidence to support the idea of a supercontinent that broke apart over time.

Continental drift can affect fossil remains by causing them to be dispersed across different continents as landmasses move. It can also result in changes to the environmental conditions where fossils are found, impacting preservation and fossil formation processes. Additionally, the movement of continents can lead to the creation of new habitats or barriers, influencing the distribution and evolution of species.

1. The rate of diffusion is directly proportional to the concentration gradient, as molecules will naturally move from an area of high concentration to low concentration.
2. Diffusion occurs faster at higher temperatures due to increased molecular motion and kinetic energy.
3. Diffusion is facilitated by a shorter distance for molecules to travel, such as through a thinner membrane or over a smaller area.

Seafloor spreading is a key component of the theory of continental drift. As new oceanic crust forms at mid-ocean ridges during seafloor spreading, it pushes the existing crust outward on both sides of the ridge. This movement can help explain how continents have shifted positions over time due to the movement of tectonic plates.

1. Fossil evidence: If they are to far apart
2. Fit of the continents: Fit very well at continental shelves
3. Rock and structural similarities: Rock on different continents match
4. Paleoclimate: To warm for ice
5. Paleomagnetism: Pieces point different ways

Wegner believed that the force causing continental drift was the movement of the continents through the Earth's crust, driven by the gravitational forces associated with the rotation of the Earth. This movement was theorized to be a result of the continents floating on the denser, underlying mantle layer.

A drift key is a specialized tool used to remove or install gears or shafts from equipment such as machinery or vehicles. It typically has a tapered end that allows it to fit into tight spaces and apply firm pressure for the task at hand. Drift keys are commonly used in mechanical and automotive industries.

Climate patterns and fossil evidence can help support continental drift theory. For example, matching rock formations and fossils across continents suggest they were once connected. Additionally, similarities in climate types and geological features between distant landmasses also provide evidence for past continental connections.

Alfred Wegener used several lines of evidence to support his theory of continental drift. This included the fit of the continents like a jigsaw puzzle, similarities in rock formations and mountain ranges across different continents, matching fossils on separate continents, and paleoclimatic evidence such as glacial striations in tropical regions. These pieces of evidence led Wegener to propose the theory of continental drift in the early 20th century.

Genetic drift is a random process that can lead to fluctuations in gene frequencies within a population over time. It is more prominent in smaller populations where chance events can have a bigger impact. Over generations, genetic drift can lead to the fixation of certain alleles and the loss of others, resulting in changes to the genetic makeup of a population.

the mechanism for continental drift was not well understood at the time, and there was no evidence to support the idea of continents moving. It wasn't until the theory of plate tectonics was developed that the idea of continental drift became widely accepted.

It is because he couldn't explain why or how the continent's drifted apart. They didn't believe him until after he died.

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More to the point, they didn't believe him until new techniques showed hitherto-hidden evidence.

The shapes of different coastlines can provide evidence for continental drift because some coastlines on different continents appear to fit together like pieces of a jigsaw puzzle. For example, the coastlines of South America and Africa have similar shapes and can be fitted together. This suggests that these continents were once joined together and later drifted apart.

The seafloor spreading hypothesis suggests that the primary cause of continental movement is the upwelling of magma at mid-ocean ridges, which creates new oceanic crust. The movement of this newly-formed crust pushes the existing seafloor apart, leading to the gradual separation and movement of the continents.

Evidence supporting the theory of continental drift includes the jigsaw-like fit of continents, similarities in rock formations and fossils across continents, and matching mountain belts on different continents. Additionally, the discovery of mid-ocean ridges and magnetic striping on the ocean floor provided further evidence for plate tectonics.

I believe his first observation was the way the continents of South America and Africa "fit" together like a jigsaw puzzle (although he was not the first to realize this). He also made note of fossil discoveries in Africa which corresponded to those in South America. Finally, he began his own research which actually alligned rock formation/componants from one side of the Atlantic with the other.

Natural Selection as you probably know, is the mechanism by which a species (or genetic makeup of a breeding group) changes in response to an environmental challenge. For example, imagine a population of brown rabbits in a field. They are happy, breeding and being eaten occasionally by foxes until over time, the environment changes so that the field is covered in snow.

Now, the brown rabbits stick out and the foxes have an easy time of hunting them. Consequently, the number of brown rabbits decreases dramatically and they are threatened with extinction. The genetic mutations always present in the population (and which increase with in-breeding in small populations) throw up random variations as always but now, some are more beneficial. For instance white rabbits which used to be caught and eaten quickly before the snow came, are now much better adapted. As such, they are more likely to survive, breed and pass on their white genetic make up and hence more white rabbits are born - they are naturally selected by the snow and the foxes; their environment.

GD is also a change in genetic make up of a population however it is not stimulated by the environment. Imagine our population of rabbits again. 50% of them have blue eyes and 50% have green. The eye colour makes little difference to their survival chances and is just a natural variation. A new born rabbit will statistically have a 50% chance of blue eyes and 50% chance of green eyes.

In a big population, the proportion of blue to green is likely to stay at or around 50%. However that is not the case in a small population.

Imagine there are now only 20 rabbits: 10 with blue eyes, 10 with green. Purely by chance, some of these rabbits will not breed, or some breed more often. Let's say - by chance - one green-eyed rabbit gets run over and doesn't breed. There are 10 blues and 9 greens. That means that there are now 53% blues and 47% greens. These proportions will now have a greater impact on the consequent generation since there are more blues, there will be a greater chance of blues appearing in the next generation and less chance of greens.

Populations like this constantly vary due to any number of random events. In small populations, those random events become more important since they represent a greater proportion of the total population.

In large populations, this drift is small and frequently reversed however in small populations it is almost inevitable that one of the two (or more) traits will eventually be lost from the population.

So with NS, a specific trait increases in the population because it is better adapted to the changed environment.

With GD, a specific trait increases in the population simply because a random event caused there to be slightly more of one and less of another leading to the more populous being more likely to breed

No, the Statue of Liberty is not moving backwards due to continental drift. The statue is firmly anchored to Liberty Island in New York Harbor and is not affected by the slow movement of tectonic plates that make up the Earth's crust.

Continental drift is influenced by tectonic plate movement. Over 200 million years, the continents may continue to drift apart as tectonic plates move at a rate of a few centimeters per year.Exact distances are difficult to predict due to uncertainties in plate movement and geological processes.

There is a phenomenon called 'magnetic banding' where rock preserves the orientation of the earth's magnetic field at the time it's created at constructive plate boundaries. The earth's magnetic field flips every so often in geological history, so we see bands of rock in the sea floor with alternating magnetic signatures. This indicates that the seafloor has spread and made new rock over time, and so the continents associated must have spread (and met in the middle at some point in the past.) Similarly, we see volcanism and earthquakes happen at destructive plate boundaries, suggesting plates are drifting and being pushed under one another, indicating that overall the plates are moving. Now we can put GPS markers all over the world and use satellites to accurately show how much certain plates have moved in a particular timeframe.

Rock types can provide evidence of continental drift by matching on opposite sides of current oceans, showing that the continents were once connected. For example, the Appalachian Mountains in North America align with the Caledonian Mountains in Scotland, indicating they were once part of the same mountain range before continental drift occurred. Additionally, similar fossils and rock formations found on different continents support the theory of continental drift.