How does natural selection to adaptations develope diversity in species?

Like the birds the guy did research on, they had to adapt to their environment to survive. and different envirnments require different types of adaptation. like the penguins who live in the cold, have thicker fur, and it is waterproof, penguins found in warmer areas could run faster, and fly but not too long, cause they are still chubby.

An ecosystem is in a certain area and includes living and non living plus there is weather conditions and a biome is a large amount of area with similar climate.so ecosystem is based on weather and biome is based on the average climate