History of evolutionary thought Adaptation is an observable fact of life accepted by philosophers and natural historians from ancient times, independently of their views on evolutionbut their explanations differed. In natural theologyadaptation was interpreted as the work of a deity and as evidence for the existence of God. Pangloss  is a parody of this optimistic idea, and David Hume also argued against design. The series was lampooned by Robert Knoxwho held quasi-evolutionary views, as the Bilgewater Treatises.
January 7, ] volution is the cornerstone of modern biology. It unites all the fields of biology under one theoretical umbrella. It is not a difficult concept, but very few people -- the majority of biologists included -- have a satisfactory grasp of it.
One common mistake is believing that species can be arranged on an evolutionary ladder from bacteria through "lower" animals, to "higher" animals and, finally, up to man. Mistakes permeate popular science expositions of evolutionary biology.
Mistakes even filter into biology journals and texts. For example, Lodish, et. Misunderstandings about evolution are damaging to the study of evolution and biology as a whole.
People who have a general interest in science are likely to dismiss evolution as a soft science after absorbing the pop science nonsense that abounds. The impression of it being a soft science is reinforced when biologists in unrelated fields speculate publicly about evolution.
This is a brief introduction to evolutionary biology.
I attempt to explain basics of the theory of evolution and correct many of the misconceptions. Evolution is a change in the gene pool of a population over time.
A gene is a hereditary unit that can be passed on unaltered for many generations. The gene pool is the set of all genes in a species or population. The English moth, Biston betularia, is a frequently cited example of observed evolution.
The frequency of the dark morph increased in the years following.
Their frequency was less in rural areas. The moth population changed from mostly light colored moths to mostly dark colored moths. The moths' color was primarily determined by a single gene. The increase in relative abundance of the dark type was due to natural selection. The late eighteen hundreds was the time of England's industrial revolution.
Soot from factories darkened the birch trees the moths landed on. Against a sooty background, birds could see the lighter colored moths better and ate more of them. As a result, more dark moths survived until reproductive age and left offspring.
The greater number of offspring left by dark moths is what caused their increase in frequency. This is an example of natural selection. A single organism is never typical of an entire population unless there is no variation within that population.
Individual organisms do not evolve, they retain the same genes throughout their life.
When a population is evolving, the ratio of different genetic types is changing -- each individual organism within a population does not change. For example, in the previous example, the frequency of black moths increased; the moths did not turn from light to gray to dark in concert.
The process of evolution can be summarized in three sentences: Evolution can be divided into microevolution and macroevolution. The kind of evolution documented above is microevolution. Larger changes, such as when a new species is formed, are called macroevolution.
Some biologists feel the mechanisms of macroevolution are different from those of microevolutionary change. Others think the distinction between the two is arbitrary -- macroevolution is cumulative microevolution.
The word evolution has a variety of meanings. The fact that all organisms are linked via descent to a common ancestor is often called evolution. The theory of how the first living organisms appeared is often called evolution.
This should be called abiogenesis.- Adaptation and Natural Selection In Merriam-Webster Dictionary, adaptation is defined as a “modification of an organism or its parts that makes it more fit . Like Grant Ramsey, I am less perplexed by the structure of Darwin’s Origin than Elliot Sober is.
Indeed, I suspect that Sober’s puzzles about the order in which natural selection and common ancestry are discussed are in part an artifact of an equivocation on “natural selection.”.
How does natural selection help shape the amazing types of animals we witness around us? Natural Selection & Adaptation: Natural Selection & Adaptation: Definition, Theory & Examples. I have long called myself a social conservative.
I think it is very important to have standards for behaviour (etiquette) and defined roles. The problems with this system is not that it exists, but the lack of flexibility and the value placed on them.
How does natural selection help shape the amazing types of animals we witness around us? In this lesson, we'll explore adaptations and what they can tell us about a species' past evolution. Adaptation and Natural Selection Essay Sample. Adaptation that is, the way that species’ anatomy, physiology, and behaviour appear to be well suited to the demands of their environments.