Evolution

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.

In the past century there will be a different classification of human evolution

They both employ the same mechanism: adaptation. The difference is that in one case, subpopulations diverge to adapt to differing circumstances, and in the other, separate species adapt to similar circumstances.

Evolution and classification are related because classification systems are used to organize and categorize organisms based on their shared evolutionary history and similarities. Evolutionary relationships help scientists determine how organisms are related and classify them into groups that share common ancestry, reflecting the idea that organisms have evolved over time from common ancestors.

The term 'evolution' can refer to more than one thing.

Evolution is the word used to refer to the observed changing of allele frequencies in populations of organisms, and more generally to the observed fact that life changes over time. This is a fact, and is therefore "100% true".

Evolution is also the word used to refer to the scientific model that explains observations in biology and palaeontology in terms of what we know about the facts of evolution. Scientific theories cannot technically be said to be "100% true", but the basic hypotheses of evolutionary theory are so overwhelmingly supported by the available evidence that one might as well accept them as factual.

Evolution changes the relative frequency of alleles in a gene pool through mechanisms such as natural selection, genetic drift, gene flow, and mutation. These processes can cause certain alleles to become more or less common in the population over time, leading to changes in the genetic makeup of the population. This happens because individuals with beneficial alleles that help them survive and reproduce are more likely to pass those alleles on to the next generation, increasing their frequency in the gene pool.

Think of coevolution as an arms race. The rabbit population develops faster running ability and the fox population must have variant individuals that can keep up and these individuals are the ones who will be reproductively successful and leave these traits to the next generation of foxes and the alleles in the fox population change in frequency. Meanwhile the slower rabbits are eliminated from the population and the faster rabbits are reproductively successful, and so on.

Only the limitations of physics and the realities of variant organisms keep this arms race within the confines of the physical and biological world.

1. Fossil record: Shows gradual changes in organisms over time, with transitional fossils linking different species.
2. Comparative anatomy: Similarities in structures across species suggest common ancestry, such as homologous structures.
3. Molecular homologies: Similarities in DNA and protein sequences provide evidence of shared ancestry, seen in genetic similarities between different species.
4. Biogeography: Distribution patterns of species across different regions reflect evolutionary history, such as unique species found on isolated islands.
5. Experimental evidence: Laboratory studies and observations in nature demonstrate evolutionary processes in action, like bacterial resistance to antibiotics.

The developers of the theory of evolution by natural selection were Charles Robert Darwin and Alfred Russel Wallace.

Yes, prokaryotes are believed to have evolved before eukaryotes. Eukaryotes likely evolved through a process of endosymbiosis, where prokaryotic cells engulfed other prokaryotic cells to form a symbiotic relationship, leading to the development of cellular organelles.

Evolution explains changes in allele frequencies over time. As these changes in allele frequencies build up over time, a population can no longer be considered to be the same species it once was.

Depending on generation lengths, these changes can take days or millions of years. When these times lengths are extremely long, it is hard to determine when exactly you would say one example is species A while another is species B; however, we have observed speciation (put "observed instances of speciation" into google) and have many other evidences that speciation occurs. For example, ERVs, biogeographical distribution of species, computational genomics and proteomics, vestigial genes and structures, ring species, and more.

Yes, migration can affect evolution by introducing new genetic diversity into populations. This can lead to adaptation to new environments and potentially drive evolutionary changes within a population. Additionally, migration can facilitate gene flow between populations, influencing genetic diversity and evolution on a larger scale.