Botany, zoology, marine biology, bacteriology, and even astrobiology are all examples of life sciences. Studying everything from the biggest creatures to the smallest we share our planet with is beneficial to human life in a variety of ways. Even astrobiology, though it is the study of the possibility of life beyond Earth, has roots on Earth as Astro biologists often study organisms able to survive in our planet's harshest environments to understand how life could form on some other celestial bodies in the universe.
Imagine if through the pursuit of botany, the study of plants, we are one day able to engineer a way to grow crops in shallow areas along the seafloor. Perhaps someday zoologists, who study not only living animals but also extinct ones, with the help of geneticists, could one day give such species like the mammoth or dodo bird a chance to once again walk on our planet.
Life sciences provide us with the opportunity to better understand our world. Through the knowledge and understanding of the fields of study mentioned above, and those that fall into this category not mentioned, we have a chance to make life on Earth not only better for humanity but also for all life that calls this planet home.