What is Free Evolution?
Free evolution is the notion that natural processes can cause organisms to develop over time. This includes the evolution of new species and transformation of the appearance of existing species.
A variety of examples have been provided of this, such as different kinds of stickleback fish that can live in either fresh or salt water and walking stick insect varieties that prefer particular host plants. These reversible traits however, are not able to explain fundamental changes in basic body plans.
Evolution by Natural Selection
Scientists have been fascinated by the development of all living organisms that inhabit our planet for ages. The most widely accepted explanation is that of Charles Darwin's natural selection process, a process that is triggered when more well-adapted individuals live longer and reproduce more successfully than those that are less well adapted. As time passes, the number of well-adapted individuals becomes larger and eventually forms an entirely new species.
Natural selection is a cyclical process that is characterized by the interaction of three elements that are inheritance, variation and reproduction. Variation is caused by mutations and sexual reproduction both of which enhance the genetic diversity of a species. 에볼루션 바카라사이트 refers the transmission of genetic traits, which include both dominant and recessive genes, to their offspring. Reproduction is the process of producing fertile, viable offspring, which includes both sexual and asexual methods.
All of these variables have to be in equilibrium for natural selection to occur. If, for instance the dominant gene allele makes an organism reproduce and live longer than the recessive gene allele, then the dominant allele will become more prevalent in a population. If the allele confers a negative advantage to survival or reduces the fertility of the population, it will go away. The process is self-reinforcing, which means that the organism with an adaptive characteristic will live and reproduce much more than one with a maladaptive characteristic. The higher the level of fitness an organism has as measured by its capacity to reproduce and survive, is the greater number of offspring it can produce. Individuals with favorable characteristics, such as having a long neck in giraffes, or bright white color patterns on male peacocks, are more likely than others to reproduce and survive, which will eventually lead to them becoming the majority.
Natural selection only affects populations, not individual organisms. This is a significant distinction from the Lamarckian theory of evolution which claims that animals acquire characteristics by use or inactivity. For example, if a animal's neck is lengthened by stretching to reach for prey, its offspring will inherit a more long neck. The difference in neck length between generations will continue until the neck of the giraffe becomes too long that it can no longer breed with other giraffes.
Evolution through Genetic Drift
In genetic drift, alleles of a gene could be at different frequencies in a population through random events. In the end, one will attain fixation (become so widespread that it can no longer be eliminated by natural selection), while other alleles fall to lower frequency. In extreme cases it can lead to a single allele dominance. The other alleles are essentially eliminated, and heterozygosity decreases to zero. In a small number of people, this could lead to the complete elimination of recessive allele. This scenario is called the bottleneck effect and is typical of an evolutionary process that occurs whenever an enormous number of individuals move to form a group.
A phenotypic 'bottleneck' can also occur when survivors of a disaster such as an outbreak or a mass hunting incident are concentrated in an area of a limited size. The survivors will carry an dominant allele, and will have the same phenotype. This can be caused by war, earthquakes or even a plague. The genetically distinct population, if it is left vulnerable to genetic drift.
Walsh Lewens, Walsh and Ariew define drift as a deviation from the expected values due to differences in fitness. They cite a famous instance of twins who are genetically identical and have identical phenotypes and yet one is struck by lightning and dies, whereas the other lives and reproduces.
This kind of drift could play a very important part in the evolution of an organism. However, it is not the only way to evolve. The primary alternative is to use a process known as natural selection, in which the phenotypic diversity of the population is maintained through mutation and migration.
Stephens asserts that there is a big difference between treating drift as a force, or an underlying cause, and treating other causes of evolution such as selection, mutation and migration as forces or causes. Stephens claims that a causal process explanation of drift allows us to distinguish it from other forces, and this distinction is vital. He further argues that drift is a directional force: that is, it tends to eliminate heterozygosity. He also claims that it also has a magnitude, that is determined by the size of the population.
Evolution by Lamarckism
When high school students study biology, they are often introduced to the work of Jean-Baptiste Lamarck (1744 - 1829). His theory of evolution, commonly referred to as "Lamarckism, states that simple organisms evolve into more complex organisms by inheriting characteristics that result from the organism's use and misuse. Lamarckism is usually illustrated with an image of a giraffe that extends its neck further to reach the higher branches in the trees. This could cause giraffes' longer necks to be passed onto their offspring who would then become taller.
Lamarck was a French zoologist and, in his lecture to begin his course on invertebrate zoology at the Museum of Natural History in Paris on the 17th May 1802, he presented an innovative concept that completely challenged the previous understanding of organic transformation. In his opinion living things had evolved from inanimate matter through an escalating series of steps. Lamarck wasn't the only one to make this claim however he was widely considered to be the first to offer the subject a thorough and general explanation.
The popular narrative is that Lamarckism was an opponent to Charles Darwin's theory of evolutionary natural selection, and that the two theories fought each other in the 19th century. Darwinism ultimately prevailed and led to what biologists refer to as the Modern Synthesis. The Modern Synthesis theory denies that acquired characteristics can be acquired through inheritance and instead suggests that organisms evolve by the symbiosis of environmental factors, such as natural selection.
Although Lamarck believed in the concept of inheritance through acquired characters and his contemporaries paid lip-service to this notion, it was never a major feature in any of their evolutionary theories. This is due in part to the fact that it was never tested scientifically.
However, it has been more than 200 years since Lamarck was born and, in the age of genomics, there is a large amount of evidence that supports the heritability of acquired traits. This is sometimes referred to as "neo-Lamarckism" or, more often epigenetic inheritance. This is a model that is just as valid as the popular Neodarwinian model.
Evolution through adaptation
One of the most popular misconceptions about evolution is that it is being driven by a struggle for survival. In reality, this notion is inaccurate and overlooks the other forces that are driving evolution. The fight for survival is better described as a struggle to survive in a particular environment. 에볼루션 카지노 사이트 can include not just other organisms but also the physical environment.
To understand how evolution functions, it is helpful to understand what is adaptation. The term "adaptation" refers to any specific characteristic that allows an organism to survive and reproduce within its environment. It can be a physiological structure, like feathers or fur or a behavior such as a tendency to move to the shade during hot weather or stepping out at night to avoid the cold.
An organism's survival depends on its ability to extract energy from the surrounding environment and interact with other organisms and their physical environments. The organism must possess the right genes for producing offspring and be able find enough food and resources. Moreover, 에볼루션 카지노 사이트 must be able to reproduce itself in a way that is optimally within its environmental niche.
These factors, together with mutations and gene flow, can lead to a shift in the proportion of different alleles in the gene pool of a population. As time passes, this shift in allele frequencies could result in the development of new traits and eventually new species.
Many of the features that we admire in animals and plants are adaptations, for example, lungs or gills to extract oxygen from the air, fur or feathers to provide insulation, long legs for running away from predators and camouflage to hide. However, a proper understanding of adaptation requires a keen eye to the distinction between physiological and behavioral traits.
Physical traits such as thick fur and gills are physical characteristics. The behavioral adaptations aren't an exception, for instance, the tendency of animals to seek companionship or retreat into shade in hot temperatures. It is also important to note that lack of planning does not make an adaptation. In fact, a failure to consider the consequences of a decision can render it unadaptive, despite the fact that it might appear sensible or even necessary.