Are you learning or teaching the four types of sentences? Use this grammar quiz to test yourself or your students! There are two sections with ten questions each, and the answers are at the bottom of the page. This quiz cover the four types of sentences.
What is Darwin's Theory of Evolution? Changes that allow an organism to better adapt to its environment will help it survive and have more offspring.
Evolution by natural selection is one of the best substantiated theories in the history of science, supported by evidence from a wide variety of scientific disciplines, including paleontology, geology, genetics and developmental biology.
More simply put, the theory can be described as "descent with modification," said Briana Pobiner, an anthropologist and educator at the Smithsonian Institution National Museum of Natural History in Washington, D.
The theory is sometimes described as " survival of the fittest ," but that can be misleading, Pobiner said. Here, "fitness" refers not to an organism's strength or athletic ability, but rather the ability to survive and reproduce. For example, a study on human evolution on 1, students, published online in the journal Personality and Individual Differences in Octoberfound that many people may have trouble finding a mate because of rapidly changing social technological advances that are evolving faster than humans.
As a hypothetical example, Darwin used North American black bears, which were known to catch insects by swimming in the water with their mouths open: The idea didn't go over very well with the public.
Darwin was so embarrassed by the ridicule he received that the swimming-bear passage was removed from later editions of the book. Scientists now know that Darwin had the right idea but the wrong animal.
Instead of looking at bears, he should have instead been looking at cows and hippopotamuses. The story of the origin of whales is one of evolution's most fascinating tales and one of the best examples scientists have of natural selection.
The last shore-dwelling ancestor of modern whales was Sinonyx, top left, a hyena-like animal. Over 60 million years, several transitional forms evolved: NOAA Natural selection To understand the origin of whales, it's necessary to have a basic understanding of how natural selection works.
Natural selection can change a species in small ways, causing a population to change color or size over the course of several generations. This is called "microevolution. Given enough time and enough accumulated changes, natural selection can create entirely new species, known as "macroevolution.
Take the example of whales — using evolution as their guide and knowing how natural selection works, biologists knew that the transition of early whales from land to water occurred in a series of predictable steps.
The evolution of the blowhole, for example, might have happened in the following way: Random genetic changes resulted in at least one whale having its nostrils placed farther back on its head.
Those animals with this adaptation would have been better suited to a marine lifestyle, since they would not have had to completely surface to breathe. Such animals would have been more successful and had more offspring.
In later generations, more genetic changes occurred, moving the nose farther back on the head. Other body parts of early whales also changed. Front legs became flippers. Their bodies became more streamlined and they developed tail flukes to better propel themselves through water.
Darwin also described a form of natural selection that depends on an organism's success at attracting a mate, a process known as sexual selection. The colorful plumage of peacocks and the antlers of male deer are both examples of traits that evolved under this type of selection.
But Darwin wasn't the first or only scientist to develop a theory of evolution. The French biologist Jean-Baptiste Lamarck came up with the idea that an organism could pass on traits to its offspring, though he was wrong about some of the details.
Around the same time as Darwin, British biologist Alfred Russel Wallace independently came up with the theory of evolution by natural selection. Modern understanding Darwin didn't know anything about genetics, Pobiner said. The incorporation of genetics and Darwin's theory is known as "modern evolutionary synthesis.
Such changes are called mutations. Mutations can be caused by random errors in DNA replication or repair, or by chemical or radiation damage. Most times, mutations are either harmful or neutral, but in rare instances, a mutation might prove beneficial to the organism.
If so, it will become more prevalent in the next generation and spread throughout the population. In this way, natural selection guides the evolutionary process, preserving and adding up the beneficial mutations and rejecting the bad ones.
But natural selection isn't the only mechanism by which organisms evolve, she said. For example, genes can be transferred from one population to another when organisms migrate or immigrate, a process known as gene flow.
And the frequency of certain genes can also change at random, which is called genetic drift. A wealth of evidence Even though scientists could predict what early whales should look like, they lacked the fossil evidence to back up their claim.
Creationists took this absence as proof that evolution didn't occur.Different Types of Copywriting Copywriting is a task that is associated with almost all industries. It is so broad that it is hard to define the various disciplines that are related to it. The Green Revolution refers to a series of research, and development, and technology transfer initiatives, occurring between the s and the late s, that increased agricultural production worldwide, particularly in the developing world, beginning most markedly in the late s.
Types of revolution; * Green Revolution – Wheat and rice, It is the term given to the introduction of high-yielding varieties of seeds and the increased use of fertilizers and irrigation which provided the increase in production needed to make India self-sufficient in food grains, thus improving agriculture in India.
It was brought to India by the initiative . INDUSTRIAL REVOLUTION. INDUSTRIAL REVOLUTION. To the end of the early modern period, Europe remained a preindustrial society.
Its manufactured goods came from small workshops, and most of its machinery was powered by animals, wind, falling water, or human labor.
Pages in category "Revolutions by type" The following 37 pages are in this category, out of 37 total. This list may not reflect recent changes (). By:Lucas Lau and Frazer Black The 4 Governments of the French Revolution The Legislative Assembly The Directory The Legislative Assembly ruled from September 21st, to April 6th, The National Convention was in power from September 21st, to April 6th, The National Convention The.