Evolution

Charles Darwin is best known for his theory of evolution by natural selection, which revolutionized our understanding of the origin and diversity of life on Earth. His work, particularly his book "On the Origin of Species," provided a scientific explanation for the diversity of species and how they adapt to their environment over time. Darwin's contributions laid the foundation for the field of evolutionary biology and have had a profound impact on the study of life sciences.

Microevolution refers to small-scale changes in a population's gene pool over a few generations, resulting in adaptations within a species. Macroevolution, on the other hand, involves large-scale evolutionary changes leading to the formation of new species over longer periods of time. Both processes are driven by the same mechanisms of genetic variation and natural selection.

Charles Darwin is best known for his theory of evolution through natural selection, which revolutionized our understanding of how species evolve over time. His work, including his book "On the Origin of Species," laid the foundation for modern biology and our understanding of the diversity of life on Earth. Darwin's contributions have had a lasting impact on fields such as genetics, anthropology, and ecology.

It is often fallaciously argued that the process of natural selection described by Darwin simply modifies the mean properties of a species and does not produce new species, or that Darwin failed to produce a workable definition of species and uses the term vaguely. Other arguments include the unsubstantiated assertion that the staggering complexity found in life from the macroscopic to the molecular level cannot be the result of mindless natural processes, and the erroneous claim that no (or not enough) transitional fossils have been found.

Short answer: it isn't. In fact, it is very easy to demonstrate evolution in a laboratory, or anywhere else for that matter. All one needs is a population of organisms with a short lifecycle and a notebook. Simply count how often a number of inherited traits occur in the population, and then repeat that count a number of generations later, and you'll have demonstrated evolution.

Variations within populations is what natural selection is " looking " for. That one variant of a population is somewhat better able to survive and reproduce than other variants against the backdrop of the immediate environment is natural selection.

Two factors, both related to the availability of energy and presence of mutagens.

First, the sun was much dimmer two billion years ago; it provided about 30% less heat, and less radiation. Second, there was very little free molecular oxygen in the atmosphere. Most organisms were anaerobe. Oxygen-based metabolisms are much more energetic than anaerobe metabolisms, and on top of that, oxygen-based chemistry provides much more free radicals, which act as mutagens. So life back then was slower, as well as mutation rate.

Charles Darwin observed that the beaks of several finches on the Galapagos Islands were adapted to specific purposes, and that, while they were all finches, they had adapted different characteristics to perform different functions (different feeding for differently shaped beaks). This led him to conclude that organisms can and do change to perform necessary tasks more conveniently. He expounded upon this conclusion, eventually publishing his renowned On the Origin of Species.

People may deny the proof of evolution due to personal beliefs, religious reasons, lack of understanding of the evidence, or misinformation. Some may feel that accepting evolution conflicts with their worldview or beliefs.

Differential selection is just that, differential. Some variation is marginally superior to another variation us fitness difference, so the key is to have variation. Then natural selection will " see " this slight variation and select the better adapted trait against the background of the immediate environment.

The primary evidence supporting evolution comes from a combination of fossil records, comparative anatomy, embryology, molecular biology, and observed genetic changes over time. These pieces of evidence collectively provide a strong foundation for the theory of evolution.

Mutation, genetic drift and gene flow can all drive evolution to a degree and the last two, drift and flow, are especially powerful in small populations. But, the driver of adaptive change in all populations of organisms is natural selection.

The rise of two species from one species in a continuing process that resembles the branching of a tree or bush. This is called phylogenetic evolution and is the main driver of species arising over time.

Environmental factors don't just contribute - they are the cause of the evolution of a species.

For example, the horse is descended from a dog-sized creature called the Eohippus, which had separate toes instead of hooves, etc.

It's evolution towards the horse came about through an environmental change of some sort. Presumably, the more jungle-like terrain the Eohippus would have thrived in began to thin out, becoming more open plains.

Without trees or bushes to hide in, the Eohippus would have been easier to prey on. The ability to outrun predators would have been favoured by natural selection over the ability to hide from them. As a result, the individual toes gradually became the hooves adapted to running very quickly that we can see today. The small organism would have evolved towards the powerful modern horse.

But without that environmental change, the Eohippus would still be here today.

Evolution can exist without competition. Competition is what gives evolution a "direction"; it's what guides evolution.

Note that there's no literal competition. Individuals within a population don't go out of their way to trick one another out of resources. It's simply that some of these individuals are better at gathering resources, and at surviving, and at breeding, than other individuals. Which makes that their genes are more likely to make it to the next generation than the genes of the others.

Humans have affected evolution through activities such as hunting, habitat destruction, pollution, and introducing non-native species. These actions have led to the extinction of certain species, changes in gene pools of surviving populations, and altered ecosystem dynamics. Additionally, human-controlled environments and selective breeding have influenced the evolution of domesticated plants and animals.

species don't just form. You need to have a mutation in the DNA of an original species and if that helps them survive, (they are camouflaged from predators so they live, reproduce, etc.) the trait is passed on to their offspring. As the trait is passed on, more and more of that species is surviving and the ones that dont have the mutation die naturally from predators and natural causes. Soon, all of the old organisms die and the mutation is present in all of the animals until another mutation shows up. This happens over a long period of time for larger organisms and for bacteria it happens in hours. That is why we have not found a cure for the common cold. It constantly changes so we cannot chase it. It is much faster than our brains are. Humans dont change because all of our mutations are fixed or covered.Like glasses, blind people have sticks, deaf people have sign language, paralyzed people have wheelchairs. WE surgically remove extra toes fingers and even tails. Humans wil not evolve unless we kill of these people. Which hopefully, no one plans on doing.

Technically, theistic evolution isn't a theory. It's a religious belief. It's a belief that's widely held because many people feel that accepting the scientific theory of evolution does not conflict with their theistic beliefs.

The theory of evolution by natural selection, which is the cornerstone of biology, is the basis for immunology, evolutionary biology, ecology, biological anthropology, neurology, evolutionary development and a host of other scientific disciplines. The testable hypotheses that evolutionary theory generates reaches as far as astronomy and Lee Smolin's concept about evolving universes.

Jean-Baptiste Lamarck, a French biologist, proposed the idea of inheritance of acquired characteristics and the concept of transformational evolution. These ideas influenced Darwin's thinking on evolution and adaptation. However, Darwin's theory of natural selection ultimately diverged from Lamarck's ideas.

Physiology suggests evolution by revealing how organisms have adapted over time to better survive in their environments. Changes in physiological processes, such as metabolism or immune responses, can provide insight into how species have evolved specific traits to increase their chances of survival and reproductive success. Studying physiological adaptations helps scientists understand how species have evolved to be better suited to their ecological niche.

Speciation in new areas, like recently formed islands, is often driven by geographic isolation and genetic drift. Small founder populations can lead to rapid divergence in gene pools, creating new species adapted to the unique island environment. Natural selection and genetic mutations also play a role in speciation on new islands.