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Evolution
The scientific theory according to which populations change gradually through a process of natural selection.
5,264 Questions
B. Allopactric speciation on island archipelagos. As the organisms move from island to island rapid speciation is observed because of variations in resource acquisition more than just variation in environment. Amplified radiation is observed. Example is finches on the Galapagos Islands. Hawaii also gives this example.
What was the result of natural selection according to Charles Darwin?
The result of natural selection is that those individuals whose characteristics(health, strength, camouflage, skills etc) made them more suited to survive would indeed be the ones who survived at least long enough to successfully breed, and passed on their characteristics to their offspring.
What are some misconceptions about evolution?
2 main ideas he had which turned out to be incorrect: He speculated that genes are carried in the blood- while this is not far from the truth, it was later proved that genes are carried in each cell (and so, by a twist of fate, proving the basis of Evolutionary theory) He also made a variety of mistakes in his version of the Tree of Life- Although modern science still hasn't fully worked this one out, it has got far enough to prove that, although he was right in principal, the branching from common ancestors is more complex (more of a web of life) than in his diagrams. It is interesting that the disproving of his tree of life actually strengthens the argument for evolution.
What 3 ways does sexual reproduction increase genetic varation?
The Crossing over during meiosis I between non-sister chromatids.
The random orientations and separations of homologous chromosomes and sister chromatids during metaphase I, anaphase I and metaphase II, anaphase II.
The random fusion of male and female gametes.
The question answers itself: the characteristic is passed onto few or no offspring, and therefore will not spread throughout the population.
What is the colonial flagellate hypothesis?
Multi-cellular animals also called metazoans came from protists which were colonilized. These colonies of protists formed hollow spheres. These protists which were linked together into a hollow sphere may have had some form of specialization to then make tissue.
p^2 + 2pq + q^2 = 1
What effect does natural selection have on the frequency of a recessive lethal allele?
Perhaps not much as the recessive allele is masked in heterozygous condition. Depends on penetration and expresivity of the lethal allele, but any homozygous expression is fatal, so one can expect negative frequency selection; the freqiency is kept low by selection.
Why do you now know that inheritance of acquired characteristics is not valid?
Experiments have been done to verify inheritance of acquired characteristics, and results unanimously show that it is false.
Complex forms of life evolved over long periods of time from simpler forms?
According to the theories of Charles Darwin complex forms of life evolved over long periods of time from simpler forms.
The basic mechanisms of evolutionary change cannot be observed in nature?
No. Evolution can be observed in both nature and laboratory settings, the main problem is that it's difficult to view in humans because humans live a long time and also cover the entire planet. Since humans live so long and are everywhere, most of the mechanisms behind evolution take a very long time to have any effect.
Looking at species that don't live so long or that can possibly migrate/move, evolution is easily observed. Take ring species, a population starts at one end of a "ring" shaped land mass, the population then splits, one half moves around the ring one way while the other half moves around the ring another way. This population which was the same species with the same traits becomes very different by the time they reach the other side of the ring.
Evolution is always happening. Species are constantly changing to adapt to their surroundings. If evolution wasn't always happening, many different species would have died.
False. Organisms are never ' perfectly adapted to the environment, as evolution is blind and can not predict the future, or create anew. All is ' tinkered ' together in the organism on top of adaptions that were from past environments. Natural selection adapts as best it can to the immediate environment and carries vestigial traits and poor engineering solutions on to future generations. ( appendix and the hole in the retina for two examples of this )
While man can shape his environment only a benighted social scientists could think we, as living organisms. are beyond natural selection and evolution, or that we have been perfectly adapted to the present environment.
Evolution is a process in which something passes by degrees to a different stage, especially a more advanced or mature stage. In biology it is the sequence of events involved in the evolutionary development of a change in a species. All living things are capable of evolution.
How do you calculate Evolution Index in sales?
EI = (100 + Product Growth %) / (100 + Market Growth %) X 100
How does the human eye invalidate evolution?
It is a common fallacious argument put forward in support of creationism as opposed to evolution.
It is completely debunked by the simple fact that just because a part is necessary now, does not mean it was always necessary. A part is added because it is useful, and then later parts build on it, so that eventually the first part is necessary for all others; the otehr parts also build dependence over time, until the complexity is reached and appears irreducible.
The argument is similarly broken by the mousetrap analogy. Mousetraps were used as examples of irreducible complexity, because if you remove any part it no longer works as a mousetrap. However, as simply pointed out, removing certain parts makes a very effective catapult or a very simple tie clip.
Many more fossils have been found, some of our ancestors and we have dated the earth to be 4.5billion years old. We can take samples of ice deep in glaciers to look back into the environment at the time. We know that the further we go back in the fossil record the simpler organisms get. We can find deactivated genetic material for tails in human DNA. We have a full understanding of DNA and how it mutates and much more.
Which behaviors would some evolutionary psychologists offer as proof of their theory?
all the answers are correct
Which of Lamarck's ideas turned out to be true Which turned out to be false?
Right: adaptions to environment
wrong: acquired traits are passed on
What best describes all sauropod dinosaurs?
I would say one thing is that all sauropods were herbivores.
The relevant concept is that of the ecological niche. The daschund is adapted to the niche of being a pet for humans, and it would be very badly adapted for the niche of being a predator in the wild.
