Evolution

The branch of biology that explains both the diversity and the unity of life is called evolution. It refers to the process by which different kinds of living organisms developed and diversified from earlier forms.

Darwinism is a somewhat outdated term, referring sometimes to classical Darwinian notions of evolution by natural selection, and sometimes to the more comprehensive Modern Evolutionary Synthesis. Neither can be said to have 'gaps', per sé. The classical notion of Darwinian natural selection isn't the whole of the story, but then it never claimed to be the definitive answer - and indeed it wasn't, since it was elaborated upon, refined, strengthened by every new discovery since Darwin's time. As for the Modern Synthesis: nor does it claim to be the whole of the story. Every scientist agrees that there remain plenty of questions to be answered - in evolutionary biology as much as in every other field of science.

Smaller populations or populations split by some sort of geographic barrier.

In small populations gene flow and genetic drift would shift allele frequencies back and forth very rapidly as the population would be subject to the vagaries of the environment and the small size population effects of random effects and various sized gene flows into the populations gene pool. No selection for adaptive traits here and not enough allele shift for speciation., though enough for evolution

If a large enough population is split, say by a river or mountain range, then you have different mutations offering up different selective opportunities and if these populations remain split long enough they may lose the ability to interbreed and become two different species. This without the wash out of diversity that would plague small populations.

No.

Rats are a modern species. Humans evolved from a series of hominids and hominins, which themselves evolved from smaller mammals which survived the K-T extinction event. These smaller mammals are also what rats evolved from.

The peacock, though it is often used by creationists as an argument against evolution, is a great example of how it works. It has been proved that peahens will choose males with brighter colors. Therefor, if they continue to only mate with the brightest males, then only the brightest males will pass on their genes, and then only the brightest of that generation will pass on their genes. Over time brighter and brighter birds emerge until you have something as flamboyant and unnecessary as the peacock. Because of this, the alleles for the less bright peacocks will fade away (natural selection).

Tadpole Growing Legs

Based on the study by Abzhanov et al. (Bmp4 and Morphological Variation of Beaks in Darwin's Finches. Science 2004 ), the differences in beak shape is partly determined by the expression of a signaling factor (Bmp4). Finches that have larger and broader beaks were shown to express Bmp4 earlier in development and at higher levels. Finches with different shaped beaks were able to exploit different food sources and this allowed the many beak shapes to remain present. After hundreds (or thousands) of years, the birds diverged and became different species.

This is the idea called punctuated equilibria, by paleontologists Stephen Jay Gould and Niles Eldredge. It explains the patterns seen in the fossil record.

Kingdom Protista was created because the Eukaryotes don't have the distinctive characters of plants, animals or fungi.

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All of the Eukaryotes are mostly multi-cellular, while Protista is majority uni-cellular

Evolution is the change in allele frequency over time in a population of organisms. Change over time and a fact.

Natural selection is the nonrandom survival and reproductive success of randomly varying organisms and explains much about the fact of evolution.

Structures which are apparently different and performing different functions but their basic structure is similar are called homologous structures and indicate common ancestry eg. fore limbs of bat , whale , horse dog and man apparently different but are made up of humerus , radius , ulna , carpel , metacarpals and phalanges .

Genetic variation that can be acted on by environmental pressure. Reproductive population that results in more organisms than can be supported by the ecosystem resulting in competition for limited resources, the ability of the organism to transmit genetic information to the next generation.

Homologous features of animals are a lot more recent in contrast to evolution, where as analogous dates far back. Homologous features are similar in structure, but perform different functions, such as the human hands and dolphin flippers, which makes room to allow recent evolution comparisons while analogous consists of wings of a bee and a bird, which are completely different. When trying to determine evolutionary relationship between two species, biologists concentrate on homologous features, as analogous features would be considered useless in this case.

Well, theism is the belief in a personal god, and darwinism is darwinian evolution via natural selection, so I imagine theistic Darwinism would be accepting evolution and believing in a personal god at the same time. Christians who accept theistic Darwinism assume that the creation story found in Genesis came about due to macro evolution (i.e. the evolution of one species from another).

Think of rabbits and foxes. The faster the rabbit runs the more selection of faster foxes is happening and selection of faster rabbits is also going on at the same time. So, predator and prey drive the evolution of each other.

Variation exists within the genes of every population or species as the result of natural selection. The other reason is due to neutrality of mutations.

They are important because it helps scientists know what things looked like, what they ate, and to see if there are changes between what a certain species used to look like and what it looks like now. This helps scientists to make guesses about how animals or plants developed and changed over time.

By looking at the fossils and seeing how they change over time.

limbs wings legs arms and flippers

population

"Microevolution" describes changes that occur within a species over time, affecting traits such as color, size, or behavior. These changes are brought about by factors like natural selection, genetic drift, and mutations.

Although we may not be able to say who first defined evolution as the means by which new species arise, we do know that early pioneers of evolution theories include Jean-Baptiste Pierre Antoine de Monet, Geoffroy Saint-Hilaire and Lamarck.

Charles Darwin (1809-1892) was not the first to study evolution, but he was the first to recognise the role of natural selection in evolution. He defined the process by which evolution occurs as being natural selection, in his Theory of Evolution by Natural Selection.