The study of nekton is an important part of marine biology.

My biological clock is disrupted, and I've been having sleepless nights.

Invasive species can have a major impact on the natural environment.

Keiko is my best friend.

His behavior was not suitable for his position.

He learned the style of the painting to imitate the ancient artist.

I am majoring in microbiology at university.

Astrobiology is a very interesting field of study.

I am majoring in microbiology at university.

He is an expert in paleontology.