Because in natural selection heritable traits will be passed down allowing those species to have a better chance at survival, thus making speciation a reality.
Bird's beaks differ in shape depending on their habitat and food sources. These factors, as well as others, play into Natural Selection. Natural Selection was first coined by Charles Darwin when he went to the Galapagos Islands to study wildlife. He found that many birds on the island have different beaks. He also noticed that they ate different foods. For instance a bird with a strong, thick beak is more likely to eat hard seeds then soft star fish. Raptors (hawks, and eagles) have sharp pointed beaks for grabbing and ripping prey. The hummingbird has a long thin beak perfect for reaching into skinny flowers to drink nectar. So, each birds beak has been adapted to fit its food source.
Natural selection leads to speciation because as populations in a species change due to mutations, the less fit organisms die out, while the fit organisms survive and pass on their genes. As this process continues, the evolved population will eventually accumulate enough genetic changes, such that the evolved population can no longer produce fertile offspring with the original population, hence it is said that speciation has occurred.
The development of a new species through evolution is called speciation.
Natural selection seems to be the only selection that can drive speciation with powerful adaptive change. Sexual selection seems to stay within the species and both gene flow and genetic drift do not seem to drive speciation very well.
Natural selection is only the result of changing environments, mutation and the variation resulting therein. Natural selection is the process of adaptive change and the main mechanism of evolution that leads to speciation. Natural selection is a process as mutation and variation are grist to the mill of natural selection.
Only natural selection could be the answer here as natural selection is the main driver of adaptive change leading to evolutionary change and speciation in large populations.
Without variation natural selection would have nothing to select from that would confer survivability and reproductive success. on the organisms being selected against the organisms conspecifics and the immediate environment. Mutation and sexual recombination provide the main sources of this variation that is needed to make selection work. Mutation is the variation presented that causes the real adaptive change that can lead to speciation.
Adaptive change and speciation.
by natural selection, genetic drift and geographical isolation
The development of a new species through evolution is called speciation.
how is natural selection occurring in the pollenpeepers
Natural selection seems to be the only selection that can drive speciation with powerful adaptive change. Sexual selection seems to stay within the species and both gene flow and genetic drift do not seem to drive speciation very well.
We call this speciation, and is largely driven by evolution and natural selection.
Disruptive Selection
speciation
I will assume the word you are looking for is speciation. Perhaps adaptive speciation to be precise.
Allele frequency is altered by genetic drift, natural selection, migration, mutation, or nonrandom mating. This results in a change in genetic equilibrium in a population that is evolving. Evolution leads eventually to speciation.
Adaptation and speciation through natural selection
Natural selection is only the result of changing environments, mutation and the variation resulting therein. Natural selection is the process of adaptive change and the main mechanism of evolution that leads to speciation. Natural selection is a process as mutation and variation are grist to the mill of natural selection.