What provides the best evidence for gradualism?

A species of butterfly is yellow and black in color. However, a butterfly is born that happens to be orange and yellow in color which makes it difficult to see. Over a long period of time, the yellow and black butterflies die out, because the orange and yellow color combination makes the butterflies less visible to predators.Small variations occur over time in a population of wolves – larger ears, longer teeth, and a heightened sense of smell. Wolves with these helpful traits tend to survive better than those without; as time progresses slowly, the traits gradually become the norm among the population.Over the period of many, many years, a population of elephants develops larger ears to help protect the elephants from the sun and keep them cool. This larger ear eventually becomes a physical feature of the entire population of elephants.A group of finches begins to exhibit different features from those in the rest of the population, including shorter beaks and black stripes on their wings. Eventually, the two distinct groups of birds are considered entirely separate species from one another.Changes occur among a group of tree frogs which include color patterns that help them hide from predators and poisonous skin secretions that deter predators from seeking them out as a food source. As time progresses, these traits become standard in the population of tree frogs.A bird is born with a longer beak than others in its population, which allows it to more easily forage for insects inside trees, offering it an advantage over its shorter-beaked relatives. As a great deal of time progresses, more and more birds in the population are born with this advantageous feature, eventually resulting in the entire population of birds with longer beaks.Over a long period of time, tigers develop the combination of orange and black stripes, which allow them to hide in tall grasses as they stalk their prey. This trait eventually becomes one of the distinguishing features of tigers, as the coloring on all future tigers changes to adopt the orange and black stripe coloring.Small variations appear over a long period of time among a population of penguins, including thicker coats of down that allow them to survive in very cold climates. Penguins with these traits survive much better than those with thinner down coats, leading to the changes becoming standard among all penguins.A species of flowers adapts over time to attract more bees, a morphological change that allows the flowers to spread their pollen further and increase the size of the population. The adaptation is advantageous to the flowers and, after a long period passes, the flowers all gradually adopt the adaptation.Certain moths in one population gradually adopt changes in color and wing shape. After a great deal of time, the two groups of moths develop into entirely distinct species from one another
Read more at http://examples.yourdictionary.com/examples-of-gradualism.html#vPREzBaQki3caDaG.99