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Evolution
The scientific theory according to which populations change gradually through a process of natural selection.
5,264 Questions
What is Robin Dunbars argument about brain evolution?
Robin Dunbar proposed, based on primate research, a relation between brain size and the number of social relationships an individual can maintain. Dunbar proposed, furthermore, that the evolution of language greatly reduced the mental effort required to maintain the same number of social relationships.
How this all relates to the evolution of the brain is not immediately evident to me, although it undoubtedly does.
What are some drawbacks of devolution?
There is no such thing as 'devolution'. Evolution is defined as genetic change over time. Change, even when it is observed that morphological attributes evolve that are similar to attributes that have been present earlier on in that lineage, has only one direction: forward in time.
Three stages of the insurgent state model?
An insurgent state is the concept that represents the second stage that of equilibrium. This is the stage where schools, local government and other social services that substitute for the formal state may have previously provided.
What is the function of nuclelous?
The main function of the nucleolus is the transcription of ribosomal RNA.
Do you believe in Charles Darwin's theory?
It's more of a matter of acceptance than belief. Belief implies there is no evidence, so one has to rely on faith. I personally accept the genetic, embryological, and paleontological evidence that supports Darwin's theory. It eloquently explains the diversity of life on earth today.
When was the darninim theory of evolution accepted?
The theory of evolution was accepted by scientists in 1859, Darwin's first book was published the same year that his theory was accepted.
How can solar power turn into energy?
The energy transmitted from the Sun. The upper atmosphere of Earth receives about 1.5 × 1021 watt-hours (thermal) of solar radiation annually. This vast amount of energy is more than 23,000 times that used by the human population of this planet, but it is only about one two-billionth of the Sun's massive outpouring—about 3.9 × 1020 MW. See also Sun. The power density of solar radiation measured just outside Earth's atmosphere and over the entire solar spectrum is called the solar constant. According to the World Meteorological Organization, the most reliable (1981) value for the solar constant is 1370 ± 6 W/m2. See also Solar constant. Solar radiation is attenuated before reaching Earth's surface by an atmosphere that removes or alters part of the incident energy by reflection, scattering, and absorption. In particular, nearly all ultraviolet radiation and certain wavelengths in the infrared region are removed. However, the solar radiation striking Earth's surface each year is still more than 10,000 times the world's energy use. Radiation scattered by striking gas molecules, water vapor, or dust particles is known as diffuse radiation. Clouds are a particularly important scattering and reflecting agent, capable of reducing direct radiation by as much as 80 to 90%. The radiation arriving at the ground directly from the Sun is called direct or beam radiation. Global radiation is all solar radiation incident on the surface, including direct and diffuse. See also Solar radiation. Solar research and technology development aim at finding the most efficient ways of capturing low-density solar energy and developing systems to convert captured energy to useful purposes. Also of significant potential as power sources are the indirect forms of solar energy: wind, biomass, hydropower, and the tropical ocean surfaces. With the exception of hydropower, these energy resources remain largely untapped. See also Energy sources. Five major technologies using solar energy are being developed. (1) The heat content of solar radiation is used to provide moderate-temperature heat for space comfort conditioning of buildings, moderate- and high-temperature heat for industrial processes, and high-temperature heat for generating electricity. (2) Photovoltaics convert solar energy directly into electricity. (3) Biomass technologies exploit the chemical energy produced through photosynthesis (a reaction energized by solar radiation) to produce energy-rich fuels and chemicals and to provide direct heat for many uses. (4) Wind energy systems generate mechanical energy, primarily for conversion to electric power. (5) Finally, a number of ocean energy applications are being pursued; the most advanced is ocean thermal energy conversion, which uses temperature differences between warm ocean surface water and cooler deep water to produce electricity. See also Biomass; Photovoltaic cell; Wind. Solar energy can be converted to useful work or heat by using a collector to absorb solar radiation, allowing much of the Sun's radiant energy to be converted to heat. This heat can be used directly in residential, industrial, and agricultural operations; converted to mechanical or electrical power; or applied in chemical reactions for production of fuels and chemicals. A solar energy system is normally designed to be able to deliver useful heat for 6 to 10 h a day, depending on the season and weather. Storage capacity in the solar thermal system is one way to increase a plant's operating capacity. There are four primary ways to store solar thermal energy: (1) sensible-heat-storage systems, which store thermal energy in materials with good heat-retention qualities; (2) latent-heat-storage systems, which store solar thermal energy in the latent heat of fusion or vaporization of certain materials undergoing a change of phase; (3) chemical energy storage, which uses reversible reactions (for example, the dissociation-association reaction of sulfuric acid and water); and (4) electrical or mechanical storage, particularly through the use of storage batteries (electrical) or compressed air (mechanical). See also Energy storage. Photovoltaic systems convert light energy directly to electrical energy. Using one of the most versatile solar technologies, photovoltaic systems can, because of their modularity, be designed for power needs ranging from milliwatts to megawatts. They can be used to provide power for applications as small as a wristwatch to as large as an entire community. They can be used in centralized systems, such as a generator in a power plant, or in dispersed applications, such as in remote areas not readily accessible to utility grid lines. Biomass energy is solar energy stored in plant and animal matter. Through photosynthesis in plants, energy from the Sun transforms simple elements from air, water, and soil into complex carbohydrates. These carbohydrates can be used directly as fuel (for example, burning wood) or processed into liquids and gases (for example, ethanol or methane). Biomass is a renewable energy resource because it can be harvested periodically and converted to fuel. See also Carbohydrate; Photosynthesis. Wind is a source of energy derived primarily from unequal heating of Earth's surface by the Sun. Energy from the wind has been used for centuries to propel ships, to grind grain, and to lift water. Wind turbines extract energy from the wind to perform mechanical work or to generate electricity. Ocean thermal energy conversion uses the temperature difference between surface water heated by the Sun and deep cold water pumped from depths of 2000 to 3000 ft (600 to 900 m). This temperature difference makes it possible to produce electricity from the heat engine concept. Since the ocean acts as an enormous solar energy storage facility with little fluctuation of temperature over time, ocean thermal energy conversion, unlike most other renewable energy technologies, can provide electricity 24 h a day.
What theories disprove evolution?
There are no scientific theories that disprove evolution. Evolution is a well-supported scientific theory that is backed by a vast amount of evidence from various scientific fields. Any claims to the contrary are not supported by scientific consensus.
Who authored the Theory of Evolution?
Charles Darwin developed the Theory of Evolution through his work on the mechanism of Natural Selection. This theory explains how species change over time through the process of adaptation to their environment.
Who suggested the theory of evolution?
Charles Darwin and Alfred Russel Wallace independently came up with evolution around about the same time. Darwin was the one to gain the first evidence for it, and suggested the process of natural selection as the driver of evolution.
HUH?????
What are real life examples of Darwin's theory of evolution?
An example of this theory can be seen in the Galápagos Islands. The Galápagaos are 16 islands off the coast of South America that Charles observed in 1835. These islands, we now know, were formed 4 million years ago from volcanic activity and had no life on them. Therefore, any animal living there now must have either flown or drifted to the islands. One species thriving in the Galapagos is the Marine Iguana, the only sea going Iguana (a type of lizard) in the world. So, if it is known that the Galápagos were initially empty, "Where did this Iguana come from?" Darwin asked. Other reptiles came to the Galapagos Islands like the Yellow Land Iguana from South America. Reptiles such as these, being able to survive for long periods of time without food or water, could have drifted to the Galápagos on driftwood or bark. Suppose the land Iguana had no food, due to overpopulation, and was forced to feed in the shallow waters on seaweed, small fish and molluscs. If one Iguana could swim better and could hold onto rocks better than others, even slightly, it would get more food and become stronger and healthier. It would therefore win more mates and reproduce more whilst its other brothers and sisters die from starvation. Later generations from this Iguana inherit and refine this talent and will survive and reproduce. Now, there are more of these skilled Iguanas who can also gather food from the sea. Thousands of generations later, with these traits selected, we end up with a new species, the Marine Iguana, which now far outnumbers the Land Iguana.
- Cell theory explains that all living organisms are composed of cells, which carry genetic information that is passed from one generation to the next.
- Heredity and genetics explain how traits are inherited and passed down through genes, contributing to the diversity of life.
- Evolution through natural selection describes how organisms with advantageous traits are more likely to survive and reproduce, leading to changes in populations over time and resulting in the unity and diversity of life.
What is the smallest biological unit that can evolve over time?
The smallest biological unit that can evolve over time is a population. Evolution is the change in the heritable characteristics of a population over generations. Individuals do not evolve, but rather the frequency of traits within a population changes over time.
no, taxonomy is not evolution. Taxonomy is the science of naming species. Taxonomy, though, makes evolution clearly apparent, as new species require new naming conventions, however similar they may seem.
and a "species" is defined as something that can establish its own breeding population...something that can sustain a propagating population. So horses are a species, donkeys are a species, but mules, the hybrid of horses and donkeys, are not, since they could not mate with other mules reliably to create a new "species" called mules without the help of either parent Mules, then, instead of a species, are called a hybrid.
How does overproduction of offspring create a struggle for survival?
overproduction actually helps the survival but if mjost of the eggs hatch but the more animals would mean more competetion for food and if their isn't enough food tehn the food source will become extinct and the other species that depend on that food source will die out also
Is there enough evidence to validate evolution as a theory?
For any hypothesis to be considered a theory, a scientific journal must be written and submitted to undergo rigorous peer evaluation. The theory of evolution has sufficient evidence and support to withstand the dissection from biologists around the world. However, keep in mind that the theory of evolution is not "proven" as nothing in the realm of science can be confirmed with absolute certainty.
Evolution is widely accepted among the scientifically literate. It is broadly rejected among those who hold religious objections. The theory has enjoyed tremendous success over the years, and is now considered to be the foundational theory of biology. Theodosius Dobzhansky once said, "nothing in biology makes sense except in the light of evolution." I would consider that a pretty strong validation.
monophyletic
What is the rate of evolution?
The rate of evolution can vary greatly depending on factors such as population size, mutation rate, natural selection pressure, and environmental changes. In some cases, evolution can occur rapidly, leading to significant changes in a short period of time, while in other cases, it can be slow and gradual over millions of years.
What questions oppose evolution?
Answer 1
There are no serious questions in the scientific community that create a stumbling block for evolution by natural selection. One of the main sources of negative questions concerning evolution is that those who reject the idea, usually on religious grounds, think that evolution is a replacement for all aspects of Creation and therefore target, primarily, questions that Creation answers but that Evolution says nothing about.
Evolution by natural selection only asserts that each creature, even each sex within the same creature, and the general environment exerts a selection pressure on every other creature. These selection pressures will guide a species to center on a particular variant within the species best suited for the environment. That variant will then become the new base and the selection pressures will narrow again. Over millions of years, this will result in species going extinct completely or in one area and being replaced by a different but similar species. Eventually, this will result in creatures significantly different than the original creature.
Evolution does not deal with abiogenesis which is the idea that life can come from non-life. Evolution requires something to be living to be alive for it to work. Many people raise the question of abiogenesis, which has much less evidence than evolution in order to question evolution. However, since evolution does not deal with abiogenesis, the questions are irrelevant to evolution per se.
Evolution does not deal with early cosmology, the formation of the universe, or the formation of the solar system and Earth. Evolution is a biological theory, not a physics or cosmological theory. However, some individuals will ask, "If you believe in evolution, where did the Earth come from?" Evolution has no connection to that answer. It would be like asking, "If you believe that Jesus was resurrected after three days, why did Buddha need to starve himself for forty-nine days to receive revelation?" The two fields are irrelevant to one another.
[See the discussion section for more of a debate on some semantics about evolution.]
Answer 2
Although the prevailing opinion regarding origins has the majority of scientists in support, many of these acknowledge that there are a number of questions which remain unanswered regarding evolutionary theory. Most would agree that these questions, while unresolved, do not 'oppose evolution' but are merely unresolved questions. Noted atheist and evolutionist Richard Dawkins in an interview about his book "The Greatest Show on Earth" referred to four of his favourite "unsolved mysteries" as follows:
1. The origin of life- "That is a complete mystery" he said.
2. The origin of sex.
3. The origin of consciousness.
4. The rise of morality.
(source: Boyle, A., The not-so- angry evolutionist, 14th October 2009)
The evolutionist G A Kerkut defined what is called the 'general theory of evolution' (GTE) as 'the theory that all the living forms in the world have arisen from a single source which itself came from an inorganic form.' Dawkins, as mentioned above, (as do many other evolutionists) regard this issue as one that remains to be solved. Some evolutionists try to suggest that the origin of life issue is not connected with evolution at all. However, this has not generally been so from Darwin himself onwards.
Evolutionist Gordy Slack states on this issue, "I think it is disingenuous to argue that the origin of life is irrelevant to evolution. It is no less relevant than the Big Bang is to physics or cosmology. Evolution should be able to explain, in theory at least, all the way back to the very first organism that could replicate itself...And to understand that organism fully, we would simply have to know what came before it. And right now we are nowhere close." (Slack,G What neo-creationists get right-an evolutionist shares lesson's he's learned from the intelligent design camp, The Scientist, 20 June 2008).
Other scientists highlight the following issues which remain to be addressed:
1. Information Theory (i.e. biological information): Living things contain masses of information encoded in their DNA, as well as the code-reading mechanism, together with the epigenetic code which controls gene expression. Dawkins in The Blind Watchmaker (p115) stated There is enough information capacity in a single human cell to store the Encyclopedia Brittanica, all 30 volumes of it, three or four times over." In The Greatest Show on Earth (page 405) Dawkins states, "The difference between life and non-life is a matter not of substance but information. Living things contain prodigious quantities of information.
An intelligent message always requires an intelligent sender. This would appear to be simply impossible through random unguided naturalistic means. Computer simulations where evolutionists control the result through their intelligent input and produce a result supposedly showing evolution can happen are far removed from the real world due to the unrealistic scenarios favourable to their outcome.
2. Mutations: do not create new Genetic information necessary for microbes to man evolution to work. For a dinosaur to change into a bird would require an incredible amount of new DNA to be written into its genome. Mutations are shown universally in science to be harmful in terms of the information content. Where an organism benefits from a mutation there is still no increase in information but often a loss. Dawkins himself when asked could not give one single example of an information-adding mutation.
3. Natural Selection considered to be a mechanism of evolution can only select from what is already there (and there often is a high degree of adaptability in the genome of various species e.g. all the different dog breeds but still all dogs). Nothing new is ever created by natural selection, as shown by the modern science of genetics, developed since Darwin's time. As someone aptly stated -natural selection may explain survivalof the fittest, but it doesn't explain arrival of the fittest.
4.Genetic Entropy- although estimates vary (some higher some lower) human geneticists generally agree that the human genome is accumulating around 100 new mutations per person per generation. These mutations are too small to produce measurable effects and so are not 'weeded out' by natural selection. Geneticists also note the 100's of mendelian genetic disorders in mankind. These figures also suggest strongly that mankind should not exist at all if it as old as postulated.
How does flagella relate to an amusement park?
The presence of a flagellum on some microscopic life is like an amusement park ride in that
For the ride:
- Some folks like to take a ride on it as proof of something inexplicable even a demonstrable miracle (They weren't killed.)
- They then dare engineers or scientists to do the same
- They say to the engineers or scientists "This is sooo scary you'll wish you never tried it!"
- When the engineers or scientists ride it they come back unexcited.
- They show the first group how physics and math are used to calculate the speed, banking of the curves and angles to prevent any real danger to the riders.
- They discuss safety factors and risk.
- The first group look blankly at the science and say "It was a miracle we weren't all killed!"
- They then turn to the next ride and say "What about this one? Its is sooo scary you'll wish you never tried it!"
For the flagellum:
- Creationists like to use the flagellum as proof of something inexplicable even a demonstrable miracle (irreducible complexity)
- They then dare evolutionists to do the same.
- They say to the evolutionists "This is sooo scary you'll wish you never tried it!"
- When the evolutionists examine it they come back unexcited.
- They show the creationists how genetics and evolution are used to explain the development of the flagellum from existing components of other creatures.
- They discuss mutation and adaptation .
- The creationists look blankly at the science and say "It was a miracle, we'd rather die than admit you're right. "
- They then turn to the next organ, perhaps an eye, and say "What about this one? It is sooo scary you'll wish you never tried it!"
Do scientist know the exact rate of evolution?
Yes and no.
Mutation rates are different in different organisms, and are also dependent on how long a generation is and whether the organism reproduces asexually or sexually.
There's no exact rate, but at least in humans, thanks to genetic markers, we can estimate that humans all descended from the San, in Africa about 150,000 years ago.
What is the study that can provide evidence of evolution?
The study of comparative anatomy and embryology can provide evidence of evolution by showing similarities in structures across different species, suggesting a common ancestry. Fossil records and molecular genetics can also provide evidence by tracing the evolution of species over time and showing genetic relatedness between different organisms.
