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Evolution
The scientific theory according to which populations change gradually through a process of natural selection.
5,264 Questions
The central idea of biological evolution is that all life on Earth shares a common ancestor. Over a large number of years, evolution produces diversity in forms of life due to gene flow, mutations, migration, genetic drift, and natural selection. Some things can be explained, for example, in geographical isolation. Over time a species which can not interbreed because of mountains, becomes less alike and can no longer interbreed to form fertile offspring.
Evolution explains how all living organisms share a common ancestor, providing the unity of life. At the same time, it accounts for the diversity of life through the process of natural selection, where variations that are advantageous for survival and reproduction become more prevalent in a population over time, leading to the wide array of species we see today. Evolutionary theory has become a fundamental framework for understanding the interconnectedness of all living beings and their adaptation to changing environments.
The scientific study of heredity?
The scientific study of heredity is called genetics. It involves understanding how traits are passed down from one generation to the next, and how variations in genes can result in different characteristics in individuals. Genetics encompasses topics such as inheritance patterns, gene expression, and the role of DNA in transmitting genetic information.
What does the principle of dominance state?
Basically, it states there are two forms of a gene called alleles, heterozygous in this case, and one allele masks the expression of the other allele. This is simplified, as it can get complex with co-dominance and partial dominance.
Is Evolution taught in Kansas?
Evolution is something that nobody seriously doubts, the evidence is all around. But you have in mind the Theory of Evolution by Natural Selection: a scientific theory originated by Darwin after his voyage in the Research ship Beagle. Some religious sects take exception to the element of this theory that ascribes completely new species to the mechanisms that Darwin describes, wishing to reserve the creation of species to God's work alone. Darwin's theory features: natural variation by sexual reproduction, with mutations. The elimination of most dfferent forms because they are not well-adapted to the conditions. The survival of a FEW different forms because they suit the conditions better (or the conditions have changed enough to make them more successful at present) If different forms survive and multiply, then over millions of generations, the forms of survivors can be dramatically different. It is difficult to observe the effects of millions of generations, except in creatures with very, very short lifespans - but there are many of those too: bacteria, flies and insicts for example. Even so, Darwin's theory is taught in every state of the US and every developed country because it is successful in predicting and explaining observed data: this is the test of all scientific theories. /Brian W
Why does convergent evolution happen?
Distantly related organisms can find themselves experiencing similar environmental circumstances. For example, ducks rummage for food in the mud of ponds and lakes, and the shapes of their bills reflect that adaptation. There is quite a bit of variability in bird bill shape, and for ducks the varaition which works best for their habitats is a wide shape so that food can be gathered up with mud and water then strained. In Australia, the platypus--a mammal-- feeds upon similar organisms and in a similar way. It also has a bill shaped much like a duck's, but it is not made up of similar tissue. A duck's bill is made up of a hard, horny material, similar to fingernails, while the platypus bill is made up of soft tissue. The bills of these two organsisms, while completely different structurally, converged on a similar shape due to similar dietary habits. One can find lots of other examples of this phenomenon. Consider organisms that swim in water. The optimal shape for that is elongated and smooth. Fish certainly possess that shape, but so do whales, dolphins and porpoises. Yet both groups have very different evolutionary histories, and their shapes, while similar, betray their evolutionary origins with significant differences. Fish swim with a side-to-side motion, and their tail fins are vertical. Whales, on the other hand, being descended from land-dwelling organisms, do not have backbones which bend easlily from side to side, so they swim with an up-and-down motion of the tail, and their tail fins, or flukes, are aligned horizontally.
If what you want to do is make an edible model for the nucleus, I suggest a Jawbreaker perhaps, or maybe even the head of a Tootsie Pop (the chocolate inside of it representing the nucleolus and the hard candy surrounding it representing the nuclear membrane)
Sorry if this isn't what you were looking for, but I hope it helps.
Darwin's Theory of Evolution is the widely held notion that all life is related and has descended from a common ancestor: the birds and the bananas, the fishes and the flowers -- all related. Darwin's general theory presumes the development of life from non-life and stresses a purely naturalistic (undirected) "descent with modification". That is, complex creatures evolve from more simplistic ancestors naturally over time. In a nutshell, as random genetic mutations occur within an organism's genetic code, the beneficial mutations are preserved because they aid survival -- a process known as "natural selection." These beneficial mutations are passed on to the next generation. Over time, beneficial mutations accumulate and the result is an entirely different organism (not just a variation of the original, but an entirely different creature).
What Theories are now rejected?
The evolutionary theory called the theory of acquired characteristics. The geocentric model. Spontaneous generation. Phrenology. The Ether (theorized medium for propagation of light). Aristotle's view of gravity. Newtonian mechanics (under relativistic conditions).
How did old world monkeys evolve from ancestral primates?
Old World monkeys are believed to have evolved from ancient primates that lived in Africa and Asia around 25 million years ago. Through a process of adaptation to their changing environments, these early primates eventually gave rise to the diverse group of monkeys we see today. Key evolutionary developments, such as the development of a more complex brain and improved mobility, played a crucial role in the evolution of Old World monkeys.
Approximately how long do scientists think chemical evolution took?
Scientists estimate that chemical evolution, the process by which life emerged from prebiotic molecules, likely took place over millions to billions of years on early Earth. The exact timing is difficult to pinpoint due to limited geological evidence, but it is believed to have occurred gradually over a long timescale.
What is the naturalistic theory?
The naturalistic theory is a philosophical approach that explains phenomena based on natural causes and laws, without resorting to supernatural explanations. It assumes that the natural world can be understood and explained through scientific inquiry and observation. This perspective rejects the existence of gods, spirits, or any other supernatural entities as explanatory principles for phenomena in the world.
What is an example of divergent evolution?
Basically, divergence is the "default mode" of evolution. So virtually all species you can think of would be examples of divergence. Even in cases of parallel and convergent evolution, the underlying genomes will continue to diverge. An often used example of divergent evolution in the morphological and behavioural sense is Darwin's finches.
Provide evidences relating to some policy goals and initiatives of VNAT?
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In Vietnam, the Vietnam National Administration of Tourism (VNAT) has implemented a policy goal to promote sustainable tourism practices. This is evidenced by their collaboration with international organizations to develop eco-friendly tourism initiatives and programs to preserve the country's natural and cultural heritage.
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VNAT has also prioritized the development of tourism infrastructure and services to enhance visitor experiences. Evidence of this can be seen in the government's investment in improving transportation networks, accommodations, and attractions to support the growth of the tourism industry and attract more visitors to Vietnam.
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Additionally, VNAT has launched campaigns to enhance the country's destination branding and marketing strategies to position Vietnam as a premier travel destination. This is demonstrated through their efforts to participate in international tourism fairs, promotional activities, and digital marketing campaigns to attract a diverse range of tourists from around the world.
What does spontaneous generation mean?
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Note that spontaneous generation and abiogenesis are distinct and separate concepts. For information on abiogenesis, see links below.
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Spontaneous generation is the obsolete idea that complex, modern organisms can form overnight from non-living things, hypothesized by Aristotle. For example, people used to think that maggots came from raw meat.
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Spontaneous Generation was the theory that complex, modern organisms formed overnight from non-living things. It was disproved by many people, some including Francesco Redi (1668) and Lazzaro Spallanzani (1768). Redi disproved Spontaneous Generation by putting some decaying meat in 2 jars, then covered one of them. When fly maggots appeared in only the uncovered jar, he had enough evidence to prove that the flies came from eggs and not the decaying meat because if the flies came from the meat, there would be flies in both jars. Spallanzani disproved Spontaneous Generation by putting heated broth in 2 sealed flasks, and covered on of them, somewhat like what Redi did, but with different materials. He concluded that Spontaneous Generation was illogical because the uncovered flask had microorganisms, and the sealed one did not.
What time and place did Darwin's theory occur?
Charles Darwin's theory of evolution, outlined in his book "On the Origin of Species," was published in 1859 in England during the Victorian era.
It is the reason humans and all of life on Earth exist. It is the most powerful idea ever to come into the human mind. Charles Darwin discovered the reason why we exist and in the process answered questions of the sort "What is the meaning of life?"
Why is evolution important in biology?
As far as scientific investigation has been able to determine, evolution is the means by which life as we know it has come about on our world. It is the fundamental process which underlies all of biology.
Why do humans get into groups to kill other groups of humans?
it is a style many people do the wrong things just to fit in with the so called cool crowd. like to try to get into gangs you would have to show that you are strong enough to handle life on the streets. other times people get in to gangs to make them look or feel strong. now if one gang or group kills another group it would be for reasons like a person of one group has a problem with a person of another group that would man that the whole group has a problem.another reason why is for the reason of space their turf gangs would fight for their space sometimes even kill each other.
The reasons for this behavior (which can go from small scale gangs to large scale global wars) are complex and often intertwined. what is often the reason is loyalty to one's group (usually a nation or country) who's leader has declared war (oftentimes fueled by greed, but other times for the protection of innocents). Revenge, greed for power, simple insanity, etc are usually the causes
What advantages of being multicellular have?
A multi-cellular organism often has different kinds of cells which are specialized for carrying out certain tasks. Additionally, being multi-cellular increases the capabilities of an organism- a multi-cellular can form organs such as a brain, heart, lungs etc. making a more complex living thing
What is the second law of Thermodynamic productions?
1) In general, the second laws states that all energy in the universe will head towards its lowest state. Another way of stating it is "the universe will tend towards maximum entropy" or "heat cannot of itself flow from a colder body to a warmer body."
2) All systems try to achieve a state of minimum energy and maximum randomness. any amt. of work can be converted to heat. but heat can only partially be converted to work.
Where do scientists believe chemical evolution occured?
Answers to this question vary: there are a number of hypotheses on the first origin of life. The leading thought is that the first molecular replicators came into existence near thermal vents on ocean floors, in deep caves, or in shallow waters near volcanoes.
Some hypotheses include the possibility that the molecular building blocks of life may have originated in space. Spectrographic analysis of interstellar gas clouds shows that they contain organic compounds. Laboratory simulations of primordial conditions on the planet Earth also show the formation of organic compounds including amino acids, a crucial ingredient for the evolution of life.
What is Oparin Chemical evolution theory Urey-Miller excerpts?
Oparin's theory proposes that organic molecules could have formed on early Earth through chemical reactions in a primordial soup. The Urey-Miller experiment demonstrated this by recreating the conditions of early Earth and producing amino acids, the building blocks of life. Overall, these theories suggest that life could have emerged from simple organic compounds through a series of chemical reactions over time.
What are two of the driving forces behind the process of natural selection?
Two driving forces behind natural selection are variation within a population, which creates diversity in traits, and differential reproductive success, where individuals with advantageous traits are more likely to survive and reproduce.
- Creationists and Intelligent Design scientists believe animals were created as kinds, and that variations within those kinds have occurred over time by adaptation and by manipulation, such as the genetic selection of traits by breeders of pets and livestock. Evolutionary scientists usually believe complex animals evolved from simpler life forms. They do not generally explain how the simple life forms, which are also animals, came to be, although some believe that non-living protogenic amino acids may have combined and generated life forms.
- Creation Theory is that all life comes from created kinds. There is no argument against speciation. All changes in life forms are micro-evolution, and do not add complexity or genetic material. The fossil record shows fully formed abrupt appearance and stasis (no change) in each layer. Even evolutionists admit this fact.James Crow, a modern leader for evolution theory admits, "...the details (of how evolution could have taken place) are difficult and obscure." (The Twilight of Evolution, p.48) Almost all the touted proofs for evolution show only micro-evolution (eg. Darwin's finches, the peppered moth, antibiotic resistent bacteria), which is not disputed by Creationists or Intelligent Design proponents. These changes have no increase in complexity, but merely emphasize certain pre-existing traits over others. Evolution Theory totally and directly contradicts the well-proven Second Law of Thermodynamics--the universal law of increasing entropy. Things tend toward disorder over time, unless there is outside influence. A common misconception is that 'change equals evolution.' Animals change or adapt to their environment because they already have the inbuilt genetic ability to do so. No new genetic information is added or written into the genetic code. It has also never been demonstrated that chance random processes can generate anything remotely like life. Biochemistry clearly demonstrates that even the simplest cell is incredibly complex and is easily destroyed. Water is particularly destructive. If even the simplest cell cannot arise spontaneously, neither can anything else, including the animals.
- Animals came to be God creating them. Every building has to have a builder. If you start there that at least states there has to be a higher power! Everything in the Bible is true and not one thing has ever been proven wrong.
- In Genesis 1: 20 God said, "Let the water teem with living creatures, and let birds fly above the earth across the expanse of the sky." In Genesis 1: 24 he said, "Let the land produce living creatures according to their kinds: livestock, creatures that move along the ground, and wild animals, each according to its kind." We know that the Bible is the true, inspired Word of God. So how much more proof do you need? Maybe in the beginning of the world, animals and humans lived longer, so you won't find many fossils of them. The world was pure before the Fall of Man, and we don't know how long the time between the Creation and the Fall of Man. It could have been centuries, or years, or days, or seconds. But maybe that is why you don't find many fossils of animals in the first layers of earth. And God didn't see fit to tell us how everything fit together. He just told us what we need to know, and we need to accept that. So, animals were made on the fifth and sixth days of creation.
- The fossil record shows the gradual emergence of different, and generally more complex species over time. For example, the oldest layers only contain bacteria. Newer layers contain mollusks, invertebrates, etc. The newest layers contain vertebrates.
- Creationist Theory does not explain geographic distribution. The most closely related species are generally also found in the closest proximity to each other.
- Creationist Theory does not explain vestigial structures. Vestigial structures are the leftovers of evolution that are no longer functional. For example, wings on flightless birds, remnant hindlimb/pelvic bones in whales, tailbone on humans. If we were created, why the extra spare parts?
- Creationist Theory does not explain why species' designs contain flaws. With evolution, flaws can be passed down from ancestors. Evolution only selects for the best available, but does not guarantee that the best is without flaws. Sometimes it requires a trade off. For example, primates (including humans) have a non-functional gene for synthesizing vitamin c because presumably ancestral primates had so much vitamin c in their diets from fruit that the gene was not necessary. The gene is still there, but unlike in other animals, it doesn't work, so now that our diets don't always contain enough vitamin c, we can get scurvy. Another flaw in our design is that our windpipe stems from the throat so it can be easy to die from choking. If we were simply created, then why would there be these flaws in our physical design?
- Where is the mixing of features? If animals were just created, wouldn't there be a more random mixing of features? Instead, you have groupings of species sharing many similar traits as if they were related to one another or evolved from common ancestors. For example, mammals are grouped because they all produce milk. But all mammals also are warm blooded and have hair or fur (even whales have vestigial hair in the fetal stages). Where are the feathered mammals? Where are the birds that bear live young? You can find the features of older groups appearing on groups that evolved from these groups, but you don't see traits from more recent groups on species from older groups. Sure, there are a few anomalies out there, but do a little research and evolution explains why.
- Creation is just one possible explanation for the origin of life on earth. There is no single way to demonstrate how life began. Any who claim creation are not necessarily correct. It's a war of words. Of philosophies and ideologies. And it is likely to remain so for some time. Until then, just about any argument concerning the origin of life on earth is as "valid" as the next. The Bible thumper is no more or less correct than the one who thumps a science text. Believe what you want to. But your beliefs do not invalidate those of others.
- All the proof one needs to see the changes evolution has effected are at hand. The earth has changed dramatically over the billions of years since it was formed. When life began (by what mechanism one is free to speculate on), it began a long, long time ago. As the planet changed, the life changed, evolved, to adapt to the new conditions. Or it died. It's that simple. The ideation of the tree of life (by Linnaeus) was a brilliant stroke. Modern evolutionary synthesis (MES), the state of the art construct that deals with evolution, is fact. (We just disagree amongst ourselves about abiogenesis - the mechanism of life's inception.) Many Christians are on board with MES and modern science's take on the age of the earth. Literal interpretation of the Bible leads to severe ideological conflicts. But some believe in a young earth. This seems to be adherence to obviously flawed ideology. Particularly in the face of the mountain of facts that any individual could understand. To evolutionists, young earth Christians seem to practice a form of denial on an epic scale. Intelligent Design Science is pseudo-science. It is an ideology that appears to have been designed for a single purpose: to get creation taught in public schools. The basic laws of existence state that nothing comes from nothing. However that would not preclude the possibility that life can come from nonliving things. Protenogenic amino acids are not alive, and neither are the proteins they create. However, a simple combination of proteins with the necessary levels of carbon, hydrogen and oxygen to form strong bonds could very well result in single celled organisms, which, through symbiosis could bond with others and create multi-celled organisms. These things can occur spontaneously. Science has not demonstrated they did occur that way, but it would be foolish to deny that it is possible. There is no way to prove that life here on earth did not come from somewhere else. It could have, and there is more than one explanation as to how it could have occurred.
- Some molecules, acids, a pool of lava and luck.
- If something needed to put the 'objects in question' into motion in order for them to even have a chance to bond into life, why can that not be the case to evolutionists? There is still room for evolution after the cause of motion. Also, why can the world and all life within it not have been intelligently designed but designed to evolve?
Claim: All changes in life forms are micro-evolution, and do not add complexity or genetic material.
The Science- This is simply not true. New genetic material passed through the filter of natural selection easily gives rise to complexity. Such complexity can be seen in the case of a nylon-eating bacteria. New genetic material can come about by various mechanisms. The two most dominant ones in vertebrate evolution are genetic recombination and genetic mutations. These are widely studied phenomena and have an extremely well documented scientific basis.
ClaimThe fossil record shows fully formed abrupt appearance and stasis (no change) in each layer.
The Science- I can only imagine that the author is referring to the Cambrian explosion, which is a well documented event in geology. Furthermore, there have been found countless precambrian fossiles, and first solid evidence of life dates back to roughly 3.5 Bya.
Claim-Even evolutionists admit this fact.James Crow, a modern leader for evolution theory admits, "...the details (of how evolution could have taken place) are difficult and obscure." (The Twilight of Evolution, p.48)
The Science- This is a case of quote mining and, even if quoted correctly, isn't evidence for anything. What one scientist, or any person, says about his own personal incredulity says nothing of the viability of a theory.
Claim-Almost all the touted proofs for evolution show only micro-evolution (eg. Darwin's finches, the peppered moth, antibiotic resistent bacteria), which is not disputed by Creationists or Intelligent Design proponents. These changes have no increase in complexity, but merely emphasize certain pre-existing traits over others.
The Science- I cannot emphasise the error of this statement. I return to the case of the nylon-eating bacteria, where nylon is a polymer first synthesised in the lab in 1935 by Wallace Carothers. "Macro-evolution" (mind you, biologists and geneticists alike do not differentiate between the two) is merely the result of accumulated "micro-evolution". Whereas 1+1+1=3, 1+1+1+1... would eventually equal 100, enough for one to call it macro-evolution by the "micro-macro" standard.
Claim-Evolution Theory totally and directly contradicts the well-proven Second Law of Thermodynamics--the universal law of increasing entropy.
The Science The Second Law of Thermodynamics explains how entropy tends to increase in a closed system. The way this law interacts with biology is that organisms must fight the tendency for disorder lest their cells will collapse. This is the purpose of homeostasis, a process which every organism shares. It has absolutely nothing to do with the increasing complexity of the global gene pool. Apples and oranges!
Claim-Animals change or adapt to their environment because they already have the inbuilt genetic ability to do so. No new genetic information is added or written into the genetic code.
The Science - This is a statement which simply contradicts modern research. I have already written a great deal about mutations and its mechanisms, so I won't comment further.
Claim-It has also never been demonstrated that chance random processes can generate anything remotely like life. Biochemistry clearly demonstrates that even the simplest cell is incredibly complex and is easily destroyed. Water is particularly destructive. If even the simplest cell cannot arise spontaneously, neither can anything else, including the animals.
The Science- It has been demonstrated that amino acids can be synthesised using only a mild electric current from where there were once only simple gases such as, among others, H2O (water vapour), CO (carbonmonoxide) and CH4 (methane). Furthermore, this has nothing to do with evolutionary theory. This is an entirely different field of study altogether called Abiogenesis and is in the field of Organic Chemistry rather than Evolutionary Biology. More importantly, Evolutionary theory is not dependent on Abiogenesis, and Abiogenesis is not dependent on Evolutionary theory for either to be true. This statement supposes that this is the case.
