What is the function of the structure identified by the red arrow?

What are the result of when individual components in an organism interact with others to create noval stucture and function called

Need an answer asap 45 points and brainlest to the first person to answer why do scientific theories, such as biological and chemical evolution, represent the strongest explanation of the changes observed in the fossil record. must be in sentence form how can scientific theories on evolution and the fossil record change over time? must be in sentence form

Ais a group of individuals of the same that exist together in the same place at the same time