An example is Darwin's finches.
In a group of nearby islands, Darwin discovered the presence of several finches of the same species but with differences in the shape of their beaks.
This process called adaptive radiation is an example of evolution as populations of the same finch became established on each island and over time the finches with beaks better adapted to the foods of each island saw their reproduction favored. Over the generations, this led to the marked difference in the beaks of the finches on each island.
Another example is the human
Thanks to genetic studies, it is known that the percentage of DNA kinship between humans and chimpanzees is quite high (over 90%).
However, phenotypically, humans and chimpanzees are quite different, this is because at some point they shared a common ancestor that gave rise to two species that became more and more separated until they gave rise to the current human and chimpanzee.
Another example is the samurai crab of japan
Samurai crabs are so named because their shell simulates a samurai-like face (according to Japanese villagers). This shell was obtained in a random way, possibly due to mutations. However, although this mutation had no function, the villagers decided not to eat these crabs because they believed that the samurai were reincarnated in the crabs. This gave the crabs a greater capacity for survival, causing their populations to increase. This is an example of how evolution and artificial selection work.