Evolution

Evolution is the change in populations of organisms over time while speciation is the direct result of natural selection working to select individuals with traits different enough, but beneficial enough, y drive their alleles into greater frequency in popilations so that new species have a chance of arising; either by anagenesis or phylogenesis.

Life is believed to have first begun as simple prokaryotic cells, such as bacteria, around 3.5 billion years ago. These cells lack a nucleus and other membrane-bound organelles, and are thought to be the earliest form of life on Earth.

The unit of evolution depends on the level at which genetic variation is passed on to the next generation. This can occur at the level of individuals, populations, or species. The unit of selection is the entity on which natural selection acts to drive evolutionary change.

Charles Darwin proposed the theory of evolution by natural selection in his book "On the Origin of Species" in 1859. He suggested that species evolve over time through the process of natural selection, where individuals with beneficial traits are more likely to survive and reproduce.

Darwin developed The theory of evolution by natural selection.

So, to answer you question, all of it!

You need to make a distinction between evolution, the change in allele frequency over time in a population of organisms, and natural selection, the nonrandom survival and reproductive success of randomly varying organisms. Natural selection is the main driver of evolution.

Knowledge of the ancestry, the evolutionary history of organisms is useful in helping find associations between genetic sequences and phenotypical expressions, which in turn is useful in finding treatments for both inherited conditions and acquired diseases.

Knowledge of the processes by which evolution proceeds is also useful in determining how pests are likely to react to the introduction of pesticides, how anti-biotics will affect the development of infectious agents, and so on. In this manner, knowledge of evolutionary processes benefits both medicine and agriculture.

A fairly new field that has potential uses is the field of evolutionary psychology, which allows psychologists to model human behaviour in terms of evolved predispositions. This might help predict how large groups of people are likely to respond to anything from political shifts to advertisement campaigns.

These are just a few examples of how our understanding of evolution and our evolutionary past can help people and society.

The concept of an "evolutionary ladder" or linear progression in evolution is outdated. Evolution is better understood as a branching tree where different species evolve in response to their environments, rather than progressing towards a single goal. Each species is adapted to its specific niche, and there is no hierarchy in terms of evolutionary advancement.

Organisms with adaptations that are well-suited to their environment are more likely to survive and reproduce successfully. These adaptations can help with finding food, avoiding predators, withstanding harsh conditions, or securing mates. Over time, individuals with beneficial adaptations pass them on to their offspring, leading to the evolution of traits that enhance survival and reproduction in a given environment.

There is no separate theory of evolution for humans. Human evolution is the theory of evolution applied to humans. Evolutionary theory states that modern lifeforms, including humans, derive from common ancestors through a process of reproductive variation and natural selection.

Variation provides the raw material for natural selection to act upon, leading to the differential survival and reproduction of individuals with advantageous traits. The greater the variation within a population, the higher the potential for adaptation and evolution in response to changing environmental conditions. Variation increases the likelihood of some individuals having traits that are better suited for survival and reproduction, thereby influencing the direction of selection.

Understanding evolution means recognizing that species change over time through natural selection, genetic drift, and other mechanisms, leading to the diversity of life on Earth. It involves understanding the evidence supporting evolution, such as the fossil record, comparative anatomy, and DNA sequences, and accepting that all living organisms share a common ancestry.

Microevolution is the small-scale changes that occur within a population over a short period of time. These changes typically involve adaptations to the environment or other factors that influence the gene pool of a particular species. Microevolution can include things like changes in gene frequencies, genetic drift, and natural selection.

Jean-Baptiste Lamarck proposed the theory of evolution known as Lamarckism, which suggested that organisms evolve toward perfection and complexity through the inheritance of acquired traits. This theory has been largely discredited in favor of Charles Darwin's theory of natural selection.

Evolution continues to shape the biodiversity and behavior of organisms on Earth. Understanding evolution helps us develop strategies for conservation, combatting drug resistance, and improving agricultural practices. It also provides insight into human health, disease prevention, and the development of new technologies.

Duplication can lead to the evolution of new genes with novel functions or regulatory patterns. It provides genetic redundancy that can buffer against deleterious mutations, offering evolutionary flexibility and facilitating the evolution of complex traits. Additionally, duplicated genes can diverge in function, contributing to genetic innovation and adaptation in response to changing environments.

Darwin's theory, which is no longer just Darwin's, is the bedrock on which the modern discipline of biology rests. All the disparate observations that naturalists made up to the time of Darwin suddenly had explanations. The species problem, how species arise, was, basically solved. Predictions from the theory could now be made and tested, just as they are made and tested today.

" Nothing in biology makes sense except in the light of evolution. "

Dobzanski

Evolutionary trees help us understand relationships between species, trace the path of evolution, and predict common ancestors. They provide valuable insights into biological diversity, help in conservation efforts, and assist in understanding the spread of diseases.

The evolutionary line refers to a sequence of related species derived from a common ancestor, showing the evolutionary progression from one species to another. It typically includes different stages of development and speciation that have occurred over time.

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

Natural selection is the nonrandom survival and reproductive success of randomly varying organisms.

So, if an organism is selected by having greater reproductive success than it's conspecifics this organism will leave descendents that have the traits for this success and if enough descendents start making up a greater bit of the population then genes( alleles ) will change in frequency and evolution will take place.

Natural selection is also the driver of adaptive change leading to speciation.

Selection can be both objective and subjective. Objective criteria such as qualifications, skills, and experience can be applied in the selection process. However, subjective elements like personal biases or preferences can also influence the selection decision. It is important for selection processes to be designed to minimize bias and ensure fairness.

Gradualism is the term used to describe evolution as a slow and steady process, where change occurs incrementally over time through small, gradual steps. This contrasts with punctuated equilibrium, which suggests that evolution occurs in rapid bursts separated by long periods of stability.

The morphology of embryos at various stages, and even the developmental patterns of embryos, show the same pattern of nested hierarchies that we find in morphology, behaviour and genomes, independently confirming common descent, but also teaching us how morphologies could diverge through relatively minor genetic shuffling.

The evolution of photosynthetic organisms led to the production of oxygen as a byproduct, which created the ozone layer in Earth's atmosphere. The ozone layer acts as a shield against harmful ultraviolet (UV) radiation from the sun, protecting life on Earth from its damaging effects.

The two key concepts are that slight deviations are introduced in any imperfect replication scheme, such as the way plants or animals are born, and that environmental factors play a role in determining the survivability between individuals with beneficial inheritable traits.

The interplay between these two forces, random mutation and natural selection, ultimately leads to speciation and accounts for all currently observed species, as well as those known only by their fossil remains.